JP3913768B2 - Dry toner development type image forming apparatus - Google Patents

Description

  The present invention relates to a toner seal structure such as a developing device and a cleaning device, and more particularly to a toner seal structure excellent in preventing leakage of a small particle size toner, a developing device and a cleaning device.

  2. Description of the Related Art Conventionally, in an image forming apparatus using dry toner, a seal is disposed between a blade that contacts the surface of a rotating body of a developing device or a cleaning device and its mounting base, and the toner leaks into the image forming apparatus main body. (See Patent Document 1).

  As a seal that seals between the blade and the mounting base, a seal formed of a single cell sponge or a continuous cell sponge is used. Here, the single-cell sponge refers to a sponge configured such that each cell is a single chamber and does not allow air flow, and the double-cell sponge is a reticulated tissue that allows air flow. This is a sponge that is composed of many.

Japanese Unexamined Patent Publication No. 2-271382

  However, the single-cell sponge seal is able to satisfactorily seal small-diameter toner, but because it has a structure in which gas is contained inside, the pressure between the blade and the rotating body is changed by the pressure change of the internal gas. There is a problem that the contact pressure becomes unstable. Therefore, in the developing device using such a seal, there arises a problem that the thickness of the toner layer on the surface of the developing roller becomes non-uniform. In addition, the cleaning device using such a seal causes a problem that variation occurs in the operation of removing the residual toner on the surface of the photoreceptor.

  On the other hand, since the seal of the continuous sponge has a network structure, spherical polymer toner or toner having a small particle diameter may pass between the mesh partition walls and leak to the outside. Therefore, the seal of the continuous sponge has a problem that it is not suitable for sealing a polymer toner or a small particle size toner. Here, the gas repellent sponge seal does not contain gas inside, so that the contact pressure between the blade and the rotating body does not become unstable unlike the single cell sponge.

  A technique for sealing between the blade and the mounting base with a silicon sealing material or an adhesive is also known. However, this prior art has the disadvantages that it takes time to dry the silicon sealing material and the adhesive, and that it is difficult to separate the blade from the mounting base and to reassemble the blade and the mounting base. .

Therefore, the present invention can reliably seal the polymerized toner and the small particle size toner without causing instability of the contact between the blade and the rotating body, and further, the blade and the mounting base side can be decomposed. An object of the present invention is to provide a dry toner developing type image forming apparatus provided with a cleaning device that can be easily reassembled.

The invention of claim 1 supplies toner to the surface of the rotating body to visualize the electrostatic latent image on the rotating body, scrapes off the toner remaining on the surface of the rotating body, and scrapes the toner. The present invention relates to a dry toner developing type image forming apparatus comprising a cleaning device for storing the dropped toner in a toner storage chamber. In the present invention, (1). The cleaning device comprises (a). A first blade that is pressed against the surface of the rotating body to rotate and scrapes off the toner remaining on the surface of the rotating body; and (b). A toner storage chamber for storing the toner scraped off by the first blade; (c). A second blade that is pressed against the surface of the rotating body to prevent the toner stored in the toner storage chamber from scattering and leaking to the outside of the toner storage chamber; and (d). A first blade mounting base to which the first blade is fixed; (e). A second blade mounting base to which the second blade is fixed via a seal. In addition, (2). The seal comprises (a). A portion formed of a semi-continuous sponge and sandwiched in a compressed state between the second blade mounting base and the second blade; and (b). And a portion located at both ends of the rotating body and extending from the second blade to the back side of the first blade.

According to the present invention configured as described above, since the seal disposed between the blade and the mounting base is formed of a semi-bullet sponge, it is effective even when using a polymerized toner or a small particle size toner. In addition, leakage of toner can be prevented.

Further, according to this onset bright, seals made of semi-series cells sponge, as compared to the seal made single cells sponge, without form regardless of the change in the external environment changes, exhibit desired sealing function Therefore, the blade can always be brought into sliding contact with the rotating body at a desired contact pressure, and the contact state between the blade and the rotating body is stabilized.

Furthermore, according to this onset bright, since the seal is formed of a semi-duplicate cells sponge, since it is possible to recover by placing, blowing air, in vacuum atmosphere, it is possible to reuse the seal .

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Developer)
FIG. 1 is a schematic configuration diagram of a developing device 1 having a toner sealing structure according to an embodiment of the present invention.

  As shown in FIG. 1, the developing device 1 is attached to the opening 2 a of the developing housing 2 so that the developing roller 3 (rotating body) and the supply roller 4 can rotate. Among these, the developing roller 3 conveys the toner to the developing area 6 of the photoconductor 5 and visualizes the electrostatic latent image on the photoconductor 5. The supply roller 4 is in rolling contact with the developing roller 3 to supply toner to the developing roller 3 side.

  Here, the tip of the blade 7 is in sliding contact with the developing roller 3. The blade 7 is formed of a stainless steel plate so that it can be elastically deformed, and is fixed to the lower mounting base 2 b of the opening 2 a of the developing housing 2 with a fastener 9 via a seal 8. The blade 7 is fixed to the lower mounting base 2b in a cantilever shape, and the tip of the blade 7 comes into contact with the outer surface of the developing roller 3 with a predetermined contact pressure, and the toner layer on the outer surface of the developing roller 3 The thickness of is controlled to be a desired thickness. The fastener 9 includes a plate-shaped fastening plate 9a having a flange a1 that engages with the tip of the lower mounting base 2b of the developing housing 2, and a screw 9b that is screwed to the fastening plate. The blade 7 is configured such that a portion 7a that contacts the developing roller 3 is formed of a hard member such as glass or an elastic member such as silicone rubber, and this portion 7a is provided on an elastically deformable member such as a stainless steel plate. May be.

  The seal 8 is formed in a plate shape with a semi-continuous sponge, and is attached between the blade 7 and the lower attachment base portion 2b in a compressed state of 50% or more. This semi-continuous sponge has a labyrinth-like sponge structure and can effectively seal polymerized toner and small particle size toner. In addition, this semi-bullet sponge is different from the structure of a single-cell sponge (ie, it is not a structure that contains gas inside), and is held in an initial compressed state regardless of changes in the external environment. The contact pressure between the blade 7 and the developing roller 3 does not change. Therefore, in the developing device 1 using such a seal 8, the thickness of the toner layer on the outer surface of the developing roller 3 is always regulated uniformly by the blade 7, and good development can be performed by the developing roller 3. . In addition, as described above, when the seal 8 is used in a compressed state of 50% or more, the contact state between the blade 7 and the developing roller 3 is further stabilized, and the toner sealability is further improved.

  A plastic elastic seal plate 10 is fixed to the upper mounting base 2c of the opening 2a of the developing housing 2 in a state where it can be bent and deformed. The elastic seal plate 10 has a leading end extending toward the downstream side in the rotation direction of the developing roller 3, and the leading end uniformly contacts the developing roller 3, so that the toner inside the developing housing 2 is scattered outside. Is preventing.

  In the toner container 11 on the left side of the supply roller 4 in FIG. 1, the toner is agitated to uniformly charge the toner, and the toner agitation paddle 12 that splashes the toner toward the supply roller 4 is accommodated in a rotatable manner. ing.

  According to the present embodiment configured as described above, the seal 8 disposed between the blade 7 and the lower mounting base 2b is formed of a semi-continuous sponge. Even when toner (average particle size of 9 μm or less) is used, leakage of the toner can be effectively prevented.

  In addition, as described above, according to the present embodiment, the seal 8 made of the semi-continuous sponge does not change in form regardless of changes in the external environment, and exhibits a desired sealing function. Therefore, the blade 7 can always be brought into sliding contact with the developing roller 3 with a desired contact pressure. Therefore, in this embodiment, the thickness of the toner layer on the outer peripheral surface of the developing roller 3 can be uniformly regulated by the blade 7, and good and stable image formation is possible.

  The lower mounting base 2b, the seal 8 and the blade 7 can be disassembled and reassembled with respect to the developing housing 2, and are particularly characterized in that the seal 8 can be reused. That is, the seal 8 formed of a semi-bullet sponge can be restored to its original state by blowing cleaning air when the developing device 1 is disassembled. Further, the seal 8 can be restored to its original state by being housed in the decompression chamber. Therefore, when the developing device 1 is recycled, the seal 8 is not peeled off from the lower mounting base 2b and discarded, and it is not necessary to replace the seal 8 with a new one.

  In addition, the present embodiment can simplify the assembling work of the developing device 1 by the amount that does not require time for drying or the like, as compared with the conventional example using a silicon sealing material or an adhesive.

  In addition, in this embodiment, since the gap between the developing roller and the developing housing is closed by the elastic seal plate, the effect of the seal 8 is combined with the toner from the inside of the developing housing 2 to the outside. Scattering and leakage can be effectively prevented.

(Image forming device)
FIG. 2 is a schematic configuration diagram of the image forming apparatus 20 including the developing device 1 as described above.

  Around the photosensitive member 5, a paper dust removing brush 21, a charging device 29, a developing device 1, and a transfer roller 22 are arranged. An optical unit 23 is disposed below the photoreceptor 5, and an exposure optical path 24 is formed between the charging device 29 and the developing device 1.

  A sheet material (paper or plastic sheet or the like) 26 as a transfer member stacked on the paper feed tray 25 is fed out by a paper feed roller 27 and is connected to the photoconductor 5 via a registration roller pair 28 and a sheet material supply path 30. The toner image is conveyed between the transfer roller 22 and the toner image on the photosensitive member 5 is transferred by the transfer roller 22. The sheet material 26 to which the toner image has been transferred is discharged onto the paper discharge tray 33 by the paper discharge roller pair 32 after the toner image is fixed by the fixing device 31.

  As described above, the image forming apparatus 20 configured as described above includes the developing device 1 that can prevent scattering and leakage of the polymerized toner and the small particle size toner, and the toner enters the image forming apparatus main body 34. Leakage can be effectively prevented and the sheet material 26 is not soiled by the scattered and leaked toner, so that a high-quality image can be formed.

(Cleaning device)
FIG. 3 is a schematic configuration diagram of a cleaning device 40 having a toner seal structure according to the embodiment of the present invention.

  As shown in FIG. 3, the cleaning device 40 fixes a rubber cleaning blade 41 to the cleaning blade mounting base 42 and presses the tip of the cleaning blade 41 against the surface of the photoconductor 5. The residual toner on the surface is scraped off. The residual toner scraped off is stored in the toner storage chamber 43 of the cleaning device 40, and is then conveyed to a toner recovery tank (not shown).

  The cleaning device 40 is configured to hold a concave seal 44 formed of a semi-bullet sponge between the lower blade 45 and the mounting base 46 of the lower blade 45 in a compressed state of 50% or more. . FIG. 4 shows the relationship between the concave seal 44, the lower blade 45, and the cleaning blade 41 as viewed from the inside of the cleaning device. As shown in FIG. 4, the concave seal 44 extends from the lower blade 45 to the back side of the cleaning blade 41 only at the portions located at both ends of the photoconductor 5. Accordingly, the toner scraped off from the surface of the photoconductor 5 can be reliably accommodated in the cleaning device 40 without being scattered around the photoconductor 5. The lower blade 45 is formed in a plate shape with an elastically deformable resin material and is pressed against the surface of the photosensitive member 5 (rotating member) with a predetermined pressure and scraped off from the surface of the photosensitive member 5. Is prevented from splashing and leaking outside the cleaning device 40. Here, the lower blade 45 and the seal 44 are sandwiched between the mounting base 46 and the mounting plate 48 by a mounting plate 48 fixed to the mounting base 46 with screws 47.

  In this way, if the seal 44 formed of the semi-bullet sponge is used in the cleaning device 40, the polymerization toner and the small particle size toner do not leak to the outside from between the lower blade 45 and the mounting base 46, The same effect as in the case of the developing device 1 can be obtained.

  The cleaning device 40 is provided with a cleaning blade 41 at the top in FIG. 3, and the half-bulb sponge seal may be disposed between the cleaning blade 41 and the cleaning blade mounting base 42. .

1 is a schematic configuration diagram of a developing device having a toner seal structure according to an embodiment of the present invention. 1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram of a cleaning device having a toner seal structure according to an embodiment of the present invention. FIG. It is a partial perspective view of a cleaning device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Developing apparatus, 2 ... Developing housing (accommodating part), 2a ... Opening part, 2b ... Lower mounting base (mounting base), 2c ... Upper mounting base (mounting base), 3 ... Developing roller (Rotating body), 5 ... Photoconductor (Rotating body), 7 ... Blade (first blade), 8, 44 ... Seal, 10 ... Elastic seal plate (second blade), 20 ... Image Forming device, 21 ... paper dust removing brush, 22 ... transfer roller (transfer device), 29 ... charging device, 41 ... cleaning blade (second blade), 42 ... cleaning blade mounting base (mounting base) , 43... Toner accommodating chamber (container), 45 .. lower blade (first blade), 46 .. mounting base

Claims (1)

A developing device that supplies toner to the surface of the rotating body to visualize an electrostatic latent image on the rotating body;
A cleaning device that scrapes off the toner remaining on the surface of the rotating body and stores the scraped toner in a toner storage chamber;
In a dry toner developing type image forming apparatus comprising:
(1). The cleaning device includes:
A first blade that is pressed against the surface of the rotating body to rotate and scrapes off the toner remaining on the surface of the rotating body;
A toner storage chamber for storing the toner scraped off by the first blade;
A second blade that is pressed against the surface of the rotating body to prevent the toner stored in the toner storage chamber from scattering and leaking outside the toner storage chamber;
A first blade mounting base to which the first blade is fixed;
A second blade mounting base fixed to the second blade via a seal,
(2). The seal is formed of a semi-bullet sponge, is located between the second blade mounting base and the second blade in a compressed state, is located at both ends of the rotating body, and A portion extending from the second blade to the back side of the first blade,
An image forming apparatus using a dry toner developing system.

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