JPH08146761A - Developing device of image forming device - Google Patents

Abstract

PURPOSE: To prevent a leak of toner from the opening of a developing device by making a slit in an end seal member which seals a gap between a main body casing and each end of a developing roller. CONSTITUTION: An entrance seal member 44 for sealing a gap between the housing and developing roller 43 is firmly fixed to the opening of the housing, and also the end seal member 46 for sealing the gap between each end of the developing roller 43 and the opening is bonded to it. The entrance seal member 44 is fitted in such a position where it overlaps the end seal members 46 at its both ends. The slit 46c is made in each end seal 46.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device of an image forming apparatus such as a copying machine, a facsimile machine, a printer, etc., and more specifically, to a latent image formed on the surface of a latent image bearing member with a thin layer of toner on the surface of a developing roller. The present invention relates to a sealing technique for preventing toner from spilling or scattering from a main body case in a developing device that develops an image.

[0002]

2. Description of the Related Art In a developing device, toner is agitated or conveyed in the developing device during operation, so that pressure is generated in the developing device from the opening of a main body case in which the developing roller is provided. Toner may spill or spurt out. Further, when the developing device is detached from the main body of the image forming apparatus in order to replenish the toner, if the developing device is tilted or held upside down, the toner spills out even if there is a slight gap. Therefore, as shown in FIG. 2, an end seal member 101 that seals between both ends in the longitudinal direction of the developing roller 100 and a main body case (not shown) and the gap between the developing roller 100 and the main body case are sealed. And a developing seal member 102 for preventing the toner from spilling or scattering.

However, even in this apparatus, if the length of the developing seal member 102 varies, a slight gap 103 may occur between the end seal member 101 and the developing seal member 102. The toner sometimes spills or scatters from the gap 103.

Further, the developing seal member 102 is required to be brought into contact with the developing roller 100 with a force that does not scrape off a thin layer of toner on the surface of the developing roller 100. On the other hand, the developing seal member 102 must be made of a material having a rigidity enough to seal the toner even when a toner pressure is generated in the apparatus. Therefore, it is necessary to use a Mylar sheet or the like having a certain degree of hardness. Therefore, the developing seal member 102 having a certain degree of hardness
Must be brought into contact with the developing roller 100 with a force not to scrape off the toner on the roller surface, but this is difficult.

Therefore, in order to avoid the formation of the gap 103 between the end seal member 101 and the developing seal member 102, as shown in FIGS. 3 to 5, the developing seal member 102 has both end portions 102a and 102b. End seal member 1
01, so that the developing seal member 102
The applicant previously proposed a developing device for assembling (see JP-A-4-249273). 3 is a perspective view showing a main part of the developing device, FIG. 4 is a partially enlarged view of the developing device, and FIG. 5 is a front view showing the main part of the developing device. According to this developing device, the gap between the end seal member 101 and the developing seal member 102 is satisfactorily sealed, and the toner is prevented from spilling or scattering from the gap between the two members. Further, according to this developing device, the developing seal member 1
As 02, an elastic body such as polyurethane can be used. That is, in this apparatus, the developing seal member 10
Since 2 is reinforced by the overlapping end seal members 101, even the elastic body can seal the toner whose pressure in the developing device has increased. Development seal member 102
If is made of an elastic material, a thin layer of toner on the surface of the developing roller 100 is less likely to be scraped off, as compared with the case of being made of a material having high hardness.

[0006]

However, even in this developing device, toner spills from the main body of the device,
It is difficult to completely prevent scattering. That is, in the developing seal member 102, both end portions 102a and 102b in the longitudinal direction are supported by the end seal member 101, and the other portions are not particularly supported. Therefore,
When the developing roller 100 is pressed by the end seal member 101 and the developing seal member 102 in such a state, both end portions 102a and 102b of the developing seal member 102 do not move, but other unsupported portions are pressed in the pressing direction. Try to move to. Therefore, as shown in FIG. 4, at the step portion 104 which is a boundary between the portion 102a of the developing seal member 102 supported by the end seal member 101 and the portion of the developing seal member 102 not particularly supported, The strain 102c is generated in 102. Therefore, distortion 1
By 02c, a waviness is generated in the longitudinal direction of the developing seal member 102, and a gap is formed between the seal member and the developing roller 100, and the toner is scattered or scattered from this gap. Further, due to this waviness, a part of the developing seal 102 is strongly pressed against the developing roller 100, and there is a problem that the toner on the surface of the developing roller 100 is scraped off.

Further, in this developing device, as shown in FIG. 5, the developing seal member 10 of the end seal member 101 is provided.
The vicinity of the portion where 2 abuts is deformed to form a gap 105. Therefore, the toner in the developing device may spill or scatter to the outside of the device after passing through the gap 105.

The present invention has been made in view of the above problems, and it is an object of the present invention to cause undesirable deformation of each seal member that seals between the opening and the developing roller in the developing device main body case. It is an object of the present invention to provide a developing device of an image forming apparatus capable of preventing a defective seal caused by the above.

[0009]

In order to achieve the above object, the developing device according to claim 1 is a latent image formed on the surface of a latent image carrier of an image forming apparatus by a thin layer of toner adhering to the surface. A developing roller rotatably provided in the opening of the main body case for developing, and an end seal member for sealing between the main body case and both ends of the developing roller in the longitudinal direction,
Development of an image forming apparatus including a single or a plurality of development seal members which are provided in a state of contacting the development roller in the longitudinal direction of the development roller and seal between the main body case and the development roller. In the apparatus, at least one of the developing seal members is provided at a position where both ends thereof and a part of the end seal member overlap, and a portion of the end seal member that overlaps the developing seal member. It is characterized in that a cut is provided at the boundary between the non-overlapping part and the non-overlapping part.

A developing device according to a second aspect of the present invention is the developing device according to the first aspect, wherein at least one of the developing seal members is a thin layer blade that forms a thin layer of toner on the surface of the developing roller. It is characterized by.

[0011]

In the developing device according to the first and second aspects,
Since the end seal member is provided with a cut, when the developing roller is pressed against the end seal member and the developing seal member, the portion of the end seal member overlapping the developing seal member is contracted in the pressing direction. It will be easier. Therefore,
The portion of the developing seal member that overlaps with the end seal member is more likely to move in the pressing direction than in the case where no break is provided. Therefore, the distortion and waviness of the developing seal member, which is caused by the movement of only the portion of the developing seal member which is not supported by the end seal member, in the pressing direction, does not occur. Therefore, the gap generated between the developing roller and the developing seal member due to the distortion and the waviness does not occur.

Further, as described above, when the end seal member is provided with a cut, when the developing roller is pressed between the end seal member and the developing seal member, the portion of the end seal member that overlaps the developing seal member. Contracts in the pressing direction easily. Therefore, the gap caused by the distortion in the vicinity of the boundary between the portion of the end seal member that does not contact the developer seal member and the portion that does not contact the developer seal member, which occurs when the break is not provided, does not occur.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a developing device of an electrophotographic copying machine (hereinafter referred to as a copying machine) which is an image forming apparatus will be described below. FIG. 6 is a schematic configuration diagram of the developing device according to the present embodiment and a copying machine using the developing device. This copying machine is a copying machine that forms an image using a one-component developer, and a charging device 2 and an exposure device 3 are provided around a photosensitive drum 1 as a latent image carrier that rotates in the direction of arrow A. , A developing device 4, a transfer device 5, a separating device 6, a cleaning device 7, a static eliminator 8 and the like are provided, and the recording paper 10 is fed from a paper feeding device (not shown) and conveyed by a conveying device 9. It is a copy.

In this copying machine, the charging device 2 uniformly charges the photosensitive drum 1, and the exposure device 3 forms an electrostatic latent image on the surface of the uniformly charged photosensitive drum 1. By developing the latent image by the developing device 4, a toner image is formed on the surface of the photosensitive drum 1.
Then, this toner image is superposed on the recording paper 10 conveyed by the conveying device 9, and electrostatically transferred onto the recording paper by the transfer device 5. The recording paper 10 on which the toner image is transferred is separated from the surface of the photoconductor drum 1 by the separating device 6, and then the toner image is fixed on the surface of the recording paper 10 by a fixing device (not shown), The recording paper 10 is ejected from the copying machine. On the other hand, on the surface of the photosensitive drum 1 in which the recording paper 10 is separated, the cleaning device 7 collects the residual toner, and the static eliminator 8 removes the residual charges to prepare for the next copying process.

The charging device 2 is provided at a position in contact with the photosensitive drum 1 and includes a charging roller 21 rotating in the direction of arrow B, and a blade 22 for removing foreign matters such as toner adhering to the roller surface. ing.

The cleaning device 7 is provided at a position in contact with the photosensitive drum 1, and rotates in the direction of arrow C to remove toner from the surface of the photosensitive drum 1, and the surface of the seal roller 71. The blade 72 scrapes off the toner attached to the roller from the roller and drops it to the bottom of the case 73. This case 73
The toner that has dropped to the bottom of the developing device 4 passes through a toner transport path (not shown) by the toner transport roller 74 and the developing device 4
Is transported to and used again for development. Further, a cleaning blade 75 for removing the toner on the surface of the photoconductor drum 1 not removed by the seal roller 71 is provided downstream of the seal roller 71 in the rotational direction of the photoconductor drum 1.

The developing device 4 is a dry developing device using a one-component developer. FIG. 7 is a front view showing a schematic configuration of the developing device 4, and FIG. 1 is a sectional view showing a main part of the developing device 4. A developing roller 43 is provided in an opening 42 of a housing 41 as a main body case of the developing device 4 so as to be rotatable in the arrow D direction. An inlet seal 44 as a developing seal member that seals between the housing 41 and the developing roller 43 is fixed to the lower portion of the opening 42.
As a material for the inlet seal 44, for example, a Mylar film, a leaf spring made of SUS, or the like can be appropriately used. An end seal member 46 for sealing between the housing 41 and both ends of the developing roller 43 is adhered to the opening 42 so that both ends in the longitudinal direction of the inlet seal 44 and a part thereof overlap. There is. As a material for the end seal 46, a material such as Teflon felt having a relatively small coefficient of friction and a certain elasticity is suitable. Further, the inlet seal 44 of the end seal member 46 and the portion 46 a of the end seal member 46 that overlaps with the inlet seal 44 member.
At the boundary between the non-overlapping portion and the non-overlapping portion, a cut 46c is formed in a direction parallel to the rotation axis of the developing roller 43, as shown in FIG.
Is provided.

Further, a developing roller 43 is provided above the opening 42 by a toner replenishing roller 48 which will be described later.
A blade 45 for fixing the toner supplied to the surface of the toner to a thin layer is fixed. This blade 45 is used for the housing 4
It also functions as a developing seal member that seals between 1 and the developing roller 43 and seals the toner from the housing 41 so as not to scatter. As a material of the blade 45, a metal having elasticity, mylar film, polyurethane, or the like can be used. The toner formed into a thin layer by the blade 46 is used for developing the photosensitive drum 1, so that the blade comes into contact with the surface of the developing roller 43 with an abutting force that does not scrape off the toner on the surface of the developing roller 43. It is assembled.

Further, in the casing 41, the toner replenished from the toner bottle (not shown) via the toner replenishing cover 49 into the casing is rotated in the direction of arrow E to agitate and charge the agitator. 47 and a toner replenishing roller 48 for supplying the toner agitated and charged by the agitator 47 to the developing roller 43 by rotating in the arrow F direction.

According to the copying machine and the developing device described above, since the notch 46c is provided in the end seal member 46, when the developing roller 43 is pressed by the end seal member 46 and the inlet seal member 44, The portion of the end seal member 46 that overlaps the inlet seal member 44 is likely to contract in the pressing direction. Therefore, the portion of the inlet seal member 44 that overlaps the end seal member 46 is more likely to move in the pressing direction than when the cut 46c is not provided. Therefore, the end seal member 4 of the inlet seal member 44 is
The distortion and waviness of the inlet seal member 44, which is caused by the movement of only the portion not supported by 6, in the pressing direction, is eliminated. Therefore, the developing roller and the entrance seal member 4 generated by the distortion and the waviness
4 is prevented, and toner is prevented from scattering from the gap.

Further, a cut 46c is formed in the end seal member 46.
If the inlet seal member 46 is not provided, the inlet seal member 46 is pressed against the developing roller 43 by the end seal member 46, and may be pulled by the rotation of the developing roller 43 and damaged.
However, in this developing device, the developing roller 43 rotates in the direction of arrow A as shown in FIG.
Even if is pulled in the direction of arrow G, it is supported by the step portion 46d formed in the portion of the cut 46c in a direction that resists the pulling force, and thus is less likely to be damaged.

The present invention is not limited to the developing device,
The present invention can be applied to various devices in which a rotatable roller is provided in the opening of the main body case, and it is necessary to prevent powder from spilling from the main body case to the outside through the opening. it can. For example, it can be applied to prevent toner from spilling from the opening of the case 73 in the cleaning device 7 shown in the embodiment.

More specifically, the cleaning device removes toner from the surface of the latent image carrier, and is provided with a seal roller 71 rotatably provided in the opening of the case 73, and the case 73 and the seal roller 71. An end seal member for sealing between both ends in the longitudinal direction, and the seal roller 71.
A single or plural roller seal member for sealing between the case 72 and the seal roller 71, which is provided in a state of contacting the seal roller in the longitudinal direction of
At least one of the roller seal members is provided at a position where both ends thereof and a part of the end seal member overlap each other, and the end seal member overlaps a part of the end seal member that overlaps the roller seal member. It can be configured to make a cut at the boundary with the non-existing portion. If the cleaning device is configured in this way, the same operation as described above in the operation of the invention can be performed, and the toner can be prevented from spilling or spouting from the cleaning device 7.

[0024]

According to the inventions of claim 1 and claim 2,
The gap that was created between the development seal member and the development roller due to the distortion and waviness of the development seal member will not occur, and the gap that occurred due to the deformation of the end seal member will not occur, so toner will spill from each gap. It will not be scattered or scattered.

[Brief description of drawings]

FIG. 1 is a front view showing a main part of a developing device according to an embodiment.

FIG. 2 is a perspective view showing a schematic configuration of a first conventional developing device.

FIG. 3 is a perspective view showing a schematic configuration of a second conventional developing device.

FIG. 4 is a partially enlarged view of the developing device.

FIG. 5 is a partial front view of the developing device.

FIG. 6 is a front view showing a schematic configuration of a copying machine in which the developing device according to the embodiment is used.

FIG. 7 is a front view showing a schematic configuration of a developing device according to an embodiment.

FIG. 8 is an explanatory view showing an operation of the developing device.

[Explanation of symbols]

 1 Photoconductor Drum 2 Charging Device 3 Exposure Device 4 Developing Device 5 Transfer Device 6 Separation Device 7 Cleaning Device 8 Electrification Device 9 Conveying Device 10 Recording Paper 41 Case 42 Opening 43 Developing Roller 44 Entrance Seal Member 45 Blade 46 Edge Seal Member 47 Agitator 48 Toner supply roller 100 Development roller 101 End seal member 102 Development seal member 103 Gap 104 Step 105 Gap

Claims (2)

[Claims] 1. A developing roller rotatably provided in an opening of a main body case for developing a latent image formed on a surface of a latent image carrier of an image forming apparatus with a thin layer of toner attached to the surface,
An end seal member that seals between the main body case and both ends of the developing roller in the longitudinal direction; and an end seal member that is in contact with the developing roller in the longitudinal direction of the developing roller.
A developing device for an image forming apparatus, comprising: a developing seal member or a plurality of developing seal members for sealing between the main body case and the developing roller, wherein at least one of the developing seal members has both ends thereof and The end seal member is provided at a position where a part of the end seal member overlaps, and a break is provided at a boundary portion between a portion of the end seal member that overlaps with the developing seal member and a portion that does not overlap. Developing device for image forming apparatus. 2. At least one of the developing seal members,
The developing device of the image forming apparatus according to claim 1, wherein the developing roller is a thin layer blade that forms a thin layer of toner on the surface of the developing roller.