JP7006236B2 - Developing equipment, image forming equipment - Google Patents

Description

The present invention relates to a developing device and an image forming device.

In Patent Document 1, when the developing device is located at a developing position close to the photoconductor, it is on the downstream side of the developing region of the developing carrier arranged facing the photoconductor, and is located below the developing carrier in the roll axis direction. A technique for arranging a seal member over the entire area is disclosed.

Japanese Unexamined Patent Publication No. 09-0544494

The developing apparatus includes a rotating body (development roll) that is arranged to face an image holder on which a latent image is formed and that passes a developer to the latent image while rotating. Further, in the developing apparatus, a developer accommodating portion for accommodating the developer and a rotating body accommodating portion for accommodating the rotating body with the portion of the rotating body facing the image holder exposed from the opening are formed. It has a housing. In such a configuration, the scattered developer may be discharged from the opening of the housing due to the air flow generated around the rotating rotating body.

The subject of the present invention is compared with the case where the rotating body accommodating portion of the portion downstream of the opening of the housing and upstream of the surface of the developer in the rotating direction of the rotating body is closed. This is to prevent the scattered developer from being discharged from the opening of the housing.

The developing apparatus according to the first aspect of the present invention is arranged so as to face an image holder on which a latent image is formed, and a rotating body that passes a developing agent to the latent image while rotating and a developing body that houses the developing agent. The agent accommodating portion, the rotating body accommodating portion accommodating the rotating body in a state where the portion of the rotating body facing the image holder is exposed from the opening, and the opening in the rotation direction of the rotating body. On the other hand, the accommodating opening formed on the downstream side and upstream of the surface of the developer accommodating in the developer accommodating portion and connecting the rotating body accommodating portion to the outside, and the rotating body accommodating portion. It is characterized by including a developer collecting portion for recovering the developer that has passed through the accommodating opening from the portion, and a housing in which the developer is formed.

In the developing apparatus according to the first aspect , the developing apparatus according to the second aspect of the present invention has the opening between the edge portion on the downstream side in the rotational direction of the rotating body and the image holder. A downstream edge opening for connecting the rotating body accommodating portion to the outside is formed, and the housing and the rotating body of the portion on the downstream side of the downstream edge opening and the upstream side of the accommodating opening in the rotation direction. A developer passage through which the developer discharged from the accommodating opening passes is formed between the and, and the passage width of the narrowest portion in the developer passage when viewed from the rotation axis direction of the rotating body is It is characterized in that it is wider than the opening width of the downstream edge opening.

The developing apparatus according to the third aspect of the present invention is the developing apparatus according to the first or second aspect , in which the accommodating openings are at least at both ends of the rotating body accommodating portion in the rotation axis direction of the rotating body. It is characterized by being formed.

The developing apparatus according to the fourth aspect of the present invention is the developing apparatus according to any one of the first to third aspects , wherein the developer collecting unit extends in the rotation axis direction of the rotating body. It is a feature.

The developing apparatus according to the fifth aspect of the present invention is the developing apparatus according to the third aspect . It is characterized in that it extends toward the center of the rotating body.

In the developing apparatus according to the sixth aspect of the present invention, in the developing apparatus according to the fourth aspect , a penetrating portion is formed on the wall extending in the direction of the rotation axis forming the developer collecting portion, and the penetrating portion is formed. Is characterized by being provided with a limiting portion that limits and captures the passage of the developer and allows the passage of air.

The developing apparatus according to the seventh aspect of the present invention is the developing apparatus according to any one of the first to sixth aspects. It is characterized in that at least a part of the agent accommodating portion is arranged so as to be sandwiched between the rotating body accommodating portion.

The image forming apparatus according to an eighth aspect of the present invention is described in any one of the first to seventh aspects , wherein the image holder holding the latent image and the latent image is developed as a developer image with a developer. It is characterized by comprising a developing device and a transfer device for transferring the developer image to a transfer target.

The image forming apparatus according to the ninth aspect of the present invention is the image forming apparatus according to the eighth aspect . A penetrating portion is formed on the wall extending in the direction of the axis of rotation that constitutes the portion, and the penetrating portion is provided with a limiting portion that restricts and captures the passage of the developer and allows the passage of air. It is characterized by including an air flow generating member for generating an air flow so that the air flows along the wall of the developing apparatus.

According to the developing apparatus of the first aspect of the present invention, the rotating body accommodating portion of the portion downstream of the opening of the housing and upstream of the surface of the developer in the rotation direction of the rotating body is provided. Compared with the case where the developer is closed, it is possible to prevent the scattered developer from being discharged from the opening of the housing.

According to the developing apparatus of the second aspect of the present invention, the scattered developer is the downstream edge opening as compared with the case where the passage width of the narrowest portion in the developer passage is narrower than the opening width of the downstream edge opening. It can be suppressed from being discharged from.

According to the developing apparatus of the third aspect of the present invention, the developing agent scattered is compared with the case where the accommodating opening is formed only in the central portion of the rotating body accommodating portion in the rotation axis direction of the rotating body. It is possible to suppress the discharge from the opening of the housing.

According to the developing apparatus of the fourth aspect of the present invention, the volume of the developing agent collecting unit is secured at a predetermined value or more as compared with the case where the developing agent collecting unit extends in a direction different from the axial direction of the rotating body. In addition, the area occupied by the developing device when viewed from the axial direction of the rotating body can be reduced.

According to the developing apparatus of the fifth aspect of the present invention, as compared with the case where the developer collecting portion extends from the accommodating opening to the side opposite to the central portion side of the rotating body in the rotation axis direction of the rotating body. It is possible to reduce the area occupied by the developing device when viewed from the radial direction of the rotating body, after securing the volume of the developing agent collecting unit in a predetermined amount or more.

According to the developing apparatus of the sixth aspect of the present invention, the area of the penetrating portion provided with the limiting portion as compared with the case where the penetrating portion is formed on the wall whose plate surface faces the axial direction of the rotating body. Can be increased.

According to the developing apparatus of the seventh aspect of the present invention, as compared with the case where the developer collecting portion is arranged on the opposite side of the rotating body accommodating portion across the rotating body accommodating portion when viewed from the rotation axis direction of the rotating body. Therefore, the area occupied by the developing device in the direction intersecting the sandwiching direction when viewed from the rotation axis direction of the rotating body can be reduced.

According to the image forming apparatus of the eighth aspect of the present invention, the rotating body accommodating portion of the portion downstream of the opening of the housing and upstream of the surface of the developer in the rotation direction of the rotating body. It is possible to prevent the scattered developer from adhering to the recording medium as compared with the case where the is closed.

According to the image forming apparatus of the ninth aspect of the present invention, the limiting portion can capture a large amount of the developer as compared with the case where there is no air flow along the wall.

It is sectional drawing which shows the both ends part in the depth direction of the developing apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the central part in the depth direction of the developing apparatus which concerns on embodiment of this invention. It is sectional drawing which showed the central part in the depth direction of the developing apparatus, the photoconductor drum and the like which concerns on embodiment of this invention. (A) (B) It is a side view and a bottom view which showed the developing apparatus which concerns on embodiment of this invention. (A) (B) It is an exploded perspective view and the perspective view which showed the dust collecting part 106 of the developing apparatus which concerns on embodiment of this invention. It is an exploded perspective view which showed the developing apparatus which concerns on embodiment of this invention. It is a side view which showed the developing apparatus, the fan, and the substrate apparatus of the image forming apparatus which concerns on embodiment of this invention. It is a perspective view which showed the developing apparatus, the fan, and the substrate apparatus of the image forming apparatus which concerns on embodiment of this invention. It is a schematic block diagram which showed the image forming apparatus which concerns on embodiment of this invention. It is sectional drawing which showed the modification of the development apparatus which concerns on embodiment of this invention.

An example of the developing apparatus and the image forming apparatus according to the present embodiment will be described with reference to FIGS. 1 to 10. The arrow H shown in the figure indicates the vertical direction (vertical direction) of the device, the arrow W indicates the width direction (horizontal direction) of the device, and the arrow D indicates the depth direction (horizontal direction) of the device. ..

(Overall configuration of image forming device)
As shown in FIG. 9, the image forming apparatus 10 according to the present embodiment includes an accommodating portion 14 accommodating a sheet member P as a recording medium from below to above in the vertical direction (arrow H direction). A transport unit 16 that conveys the sheet member P accommodated in the accommodating unit 14, and an image forming unit 20 that forms an image on the sheet member P conveyed from the accommodating unit 14 by the transport unit 16 are provided in this order. There is.

[Accommodation unit 14]
The accommodating portion 14 is provided with an accommodating member 26 that can be pulled out from the housing 10A of the image forming apparatus 10 toward the front side in the depth direction of the apparatus, and the seat member P is loaded on the accommodating member 26. Further, the accommodating portion 14 is provided with a delivery roll 30 for delivering the highest-level sheet member P loaded on the accommodating member 26 to the transport path 28 constituting the transport unit 16.

[Transport unit 16]
The transport unit 16 is provided with a plurality of transport rolls 32 that transport the sheet member P along the transport path 28.

[Image forming unit 20]
The image forming unit 20 includes an image forming unit 18 that can be attached to and detached from the housing 10A and forms a black toner image, and an exposure unit as an example of an exposure member that irradiates an exposure light to a photoconductor drum 36 described later. 42 is provided. Further, the image forming unit 20 includes a transfer roll 44 that transfers the toner image formed by the image forming unit 18 to the sheet member P, and a fixing device 46 that fixes the toner image to the sheet member P by heat and pressure. It is prepared.

Further, the image forming unit 18 includes a photoconductor drum 36, a charging roll 38 for charging the surface of the photoconductor drum 36, and an electrostatic latent image formed on the photoconductor drum 36 by being irradiated with exposure light by the exposure unit 42. It is provided with a developing device 40 that develops an image (an example of a latent image) and visualizes it as a toner image. The photoconductor drum 36 is an example of an image holder.

(Action of image forming device)
In the image forming apparatus 10, an image is formed as follows.
First, the charging roll 38 to which the voltage is applied uniformly negatively charges the surface of the photoconductor drum 36 at a predetermined potential. Subsequently, the exposure unit 42 irradiates the surface of the charged photoconductor drum 36 with the exposure light based on the data input from the outside to form an electrostatic latent image.

As a result, an electrostatic latent image corresponding to the data is formed on the surface of the photoconductor drum 36. Further, the developing device 40 develops this electrostatic latent image and visualizes it as a toner image.

Therefore, the sheet member P sent out from the accommodating member 26 to the transport path 28 by the delivery roll 30 is sent out to the transfer position T where the photoconductor drum 36 and the transfer roll 44 come into contact with each other. At the transfer position T where the photoconductor drum 36 and the transfer roll 44 come into contact with each other, the sheet member P is sandwiched and conveyed by the photoconductor drum 36 and the transfer roll 44, so that the toner image on the surface of the photoconductor drum 36 is a sheet. Transferred to member P.

The toner image transferred to the sheet member P is fixed to the sheet member P by the fixing device 46. Then, the sheet member P on which the toner image is fixed is discharged to the outside of the housing 10A by the transport roll 32.

(Main part composition)
Next, the developing device 40 will be described.
As shown in FIG. 3, the developing apparatus 40 includes a housing 72, a developing roll 60 arranged to face the photoconductor drum 36, and a supply auger 66 for supplying the developing agent G to the developing roll 60. It is provided with a stirring auger 68 for stirring the developer G. The developing roll 60 is an example of a rotating body.

The developer G is a two-component developer composed of toner T and magnetic carrier particles (hereinafter referred to as “carrier C”) as main components.

[Development roll 60]
The developing roll 60 is arranged below the photoconductor drum 36 and facing the photoconductor drum 36 as described above. Further, a gap (development gap) for passing the developer G from the developing roll 60 to the electrostatic latent image formed on the photoconductor drum 36 is formed between the developing roll 60 and the photoconductor drum 36. ..

The developing roll 60 has a magnet roll 60A having a circular cross section extending in the depth direction of the device and a sleeve 60B having a cylindrical cross section extending in the depth direction of the device, which is placed on the magnet roll 60A and rotates around the magnet roll 60A. And have. The sleeve 60B is adapted to rotate in the arrow R1 direction (clockwise direction) in the drawing with the device depth direction as the rotation axis direction by transmitting a rotational force from a drive source (not shown).

In this configuration, the rotating developing roll 60 passes the developer G held on the surface of the developing roll 60 to the electrostatic latent image formed on the photoconductor drum 36.

[Supply auger 66, stirring auger 68]
The supply auger 66 is arranged diagonally below the developing roll 60, as shown in FIG. The supply auger 66 includes a supply shaft 66A extending in the depth direction of the device and a supply blade 66B formed on the outer peripheral surface of the supply shaft 66A. The supply auger 66 rotates by transmitting a rotational force from a drive source (not shown).

The stirring auger 68 is arranged on the opposite side of the developing roll 60 with the supply auger 66 interposed therebetween. The stirring auger 68 includes a stirring shaft 68A extending in the depth direction of the device and a stirring blade 68B formed on the outer peripheral surface of the stirring shaft 68A. The stirring auger 68 rotates by transmitting a rotational force from a drive source (not shown).

[Case 72]
The housing 72 is arranged below the photoconductor drum 36. Then, in the portion of the housing 72 facing the photoconductor drum 36, an opening 72A connecting the inside of the housing 72 to the outside extends in the depth direction of the device in order to make the developing roll 60 face the photoconductor drum 36. Is formed.

Further, in the housing 72, a rotating body accommodating portion 72B accommodating the developing roll 60 is formed on the opposite side of the photoconductor drum 36 with the opening 72A interposed therebetween extending in the depth direction of the apparatus. Further, in the housing 72, a supply path 72C in which the supply auger 66 is arranged extends diagonally below the rotating body accommodating portion 72B in the depth direction of the device. Further, in the housing 72, a stirring path 72D in which the stirring auger 68 is arranged is formed on the opposite side of the rotating body accommodating portion 72B with the supply path 72C interposed therebetween extending in the depth direction of the device. Further, in the housing 72, a partition wall 72E that separates the supply path 72C and the stirring path 72D is formed between the supply path 72C and the stirring path 72D. A developer accommodating portion 74 in which the developer G is accommodated is formed in the supply path 72C and the stirring path 72D.

The supply path 72C and the stirring path 72D have a U-shaped cross section. Further, the partition wall 72E separates the supply path 72C and the stirring path 72D except for the portion of the supply path 72C on the inner side in the depth direction of the device and the portion on the front side in the depth direction of the device. Then, in the housing 72, a continuous passage connecting the supply path 72C and the stirring path 72D is formed in a portion of the supply path 72C on the inner side in the device depth direction and a portion on the front side in the device depth direction, respectively. ing.

In this configuration, the rotating supply auger 66 and the stirring auger 68 allow the developer G to pass the developer G through the communication passage on the front side in the device depth direction of the supply path 72C and the communication path on the back side in the device depth direction. And the stirring path 72D. Then, the rotating supply auger 66 supplies the developer G to the rotating developing roll 60, whereby the rotating developing roll 60 holds the developer G.

Further, as shown in FIG. 1, in the rotation direction of the developing roll 60 (hereinafter referred to as “roll rotation direction”), the surface of the developing agent G on the downstream side of the opening 72A and the developing agent accommodating portion 74 (in the figure). A housing opening 62 for connecting the rotating body accommodating portion 72B to the outside of the rotating body accommodating portion 72B is formed in the housing 72 of the portion on the upstream side of S1). The agent surface S1 moves up and down depending on the amount of the developer G in the developer accommodating portion 74.

Specifically, the accommodating opening 62 is a hole penetrating the wall of the housing 72, and the rotating body accommodating portion 72B is placed on one side in the device width direction (on the right side in the drawing and opposite to the supply auger 66). It is open to the side). Further, as shown in FIG. 4A, a plurality of accommodating openings 62 are formed in the housing 72, and the rotating body accommodating portion 72B has a portion on the front side in the depth direction of the device and the rotating body accommodating portion 72B. It is arranged in the inner part in the depth direction of the device. Further, the accommodation opening 62 has a rectangular shape when viewed from the width direction of the device. Then, four accommodation openings 62 are arranged in the device depth direction in the front side portion in the device depth direction, and four accommodation openings 62 are arranged in the device depth direction in the device depth direction. They are lined up.

That is, the accommodating openings 62 are formed at both ends of the rotating body accommodating portion 72B in the depth direction of the device. Here, both ends of the rotating body accommodating portion 72B are portions in a range from the end portion of the rotating body accommodating portion 72B to 2 respectively, assuming that the length of the rotating body accommodating portion 72B in the device depth direction is 10.

The accommodation opening 62 on the front side in the device depth direction is arranged at the same position as the communication passage on the front side in the device depth direction connecting the supply path 72C and the stirring path 72D in the device depth direction. Further, the accommodation opening 62 on the inner side in the device depth direction is arranged at the same position as the communication passage on the inner side in the device depth direction connecting the supply path 72C and the stirring path 72D in the device depth direction. That is, even in the continuous passage, it is formed at both ends of the rotating body accommodating portion 72B in the depth direction of the device.

Further, as shown in FIG. 1, in the opening 72A, the rotating body accommodating portion 72B is connected (opened) to the outside between the edge portion 76 on the downstream side in the roll rotation direction and the photoconductor drum 36. The edge opening 78 is formed. That is, the downstream edge opening 78 is a part of the opening 72A. Further, in the roll rotation direction, the housing 72 on the downstream side of the downstream edge opening 78 and on the upstream side of the accommodating opening 62 and the developing roll 60 pass through the accommodating opening 62. A developer passage 80 through which the discharged developer G (scattered developer G) passes is formed.

When viewed from the device depth direction (direction of rotation axis of the developing roll 60), the passage width (L1 in the figure) of the narrowest portion in the developer passage 80 is the narrowest portion of the downstream edge opening 78 (opening passage). It is wider than the opening width (L2 in the figure). In the present embodiment, as an example, the passage width L1 is 1.2 [mm], and the opening width L2 is 0.6 [mm]. From the viewpoint of suppressing the scattered developer G from discharging from the downstream edge opening 78 and allowing the scattered developer G to discharge from the accommodation opening 62, the passage width L1 is 1. It is preferably 5 times or more, and more preferably 2.0 times or more the opening width L2.

When the value of the opening width L2 of the downstream edge opening 78 differs in the device depth direction, the opening width L2 compared with the passage width L1 is at the position where the accommodation opening 62 is formed in the device depth direction. The opening width is L2.

Further, as shown in FIGS. 1 and 2, a developer recovery unit 110 that collects the scattered developer G is arranged below the rotating body accommodating unit 72B. Specifically, the developer collecting unit 110 is arranged so as to sandwich a part of the developer accommodating unit 74 with the rotating body accommodating unit 72B when viewed from the depth direction of the apparatus. The developer recovery unit 110 is arranged so as not to protrude from the rotating body accommodating unit 72B toward the transport path 28 side of the sheet member P when viewed from the depth direction of the device (see FIG. 3).

Further, as shown in FIG. 8, the developer collecting unit 110 extends along the developing roll 60 in the depth direction of the apparatus (direction of the rotation axis of the developing roll 60). Specifically, in the depth direction of the device, the developer recovery unit 110 extends from one end to the other end of the rotating body accommodating unit 72B. In other words, the developer recovery unit 110 extends from both end portions where the accommodating openings 62 are arranged toward the central portion in the longitudinal direction of the developing roll 60 in the depth direction of the apparatus.

Hereinafter, the configuration of the developer recovery unit 110 will be described in detail.
As shown in FIG. 6, the developer recovery unit 110 is formed by a main body unit 102 that separates the outside and the developer recovery unit 110, and a dust collection unit 106 that collects scattered developer G. ..

-Main body 102-
The main body 102 includes a pair of end portions 112 of a portion on the end side in the depth direction of the device and a connecting portion 114 arranged between the pair of end portions 112 in the depth direction of the device and connecting the pair of end portions 112. ing. The pair of end portions 112 project downward as compared with the connecting portion 114.

Further, as shown in FIGS. 1 and 2, the end portion 112 and the connecting portion 114 of the main body portion 102 are the partition plate 72G of the housing 72 forming the bottom surface of the developer accommodating portion 74 or the rotating body accommodating portion 72B. It has a pair of side plates 102A protruding downward from the surface. In the pair of side plates 102A, the plate surfaces face in the device width direction and are separated in the device width direction.

Further, the end 112 of the main body 102 has a bottom plate 102B connecting the lower ends of the pair of side plates 102A, as shown in FIG. As described above, in the end 112 of the main body 102, the region surrounded by the partition plate 72G, the pair of side plates 102A, and the bottom plate 102B is the developer recovery unit 110.

Further, a recovery opening 116 for connecting the developer recovery unit 110 to the outside of the developer recovery unit 110 is formed on the side plate 102A on one side (right side in FIG. 1) of the end portion 112 in the width direction of the apparatus. The recovery opening 116 opens the developer recovery section 110 on one side in the width direction of the apparatus. Further, a plurality of recovery openings 116 are formed and are arranged below the accommodation opening 62 as shown in FIG. 4 (A). Further, the recovery opening 116 has a rectangular shape when viewed from the width direction of the device. Then, as shown in FIG. 1, the recovery opening 116 and the accommodation opening 62 are partitioned in the vertical direction by a partition plate 72F whose plate surface faces in the vertical direction of the device.

Here, the developing device 40 includes a pair of film materials 104 that cover the accommodating opening 62 and the recovery opening 116. The film material 104 will be described.
As shown in FIGS. 1, 4 (A), and 6, the film material 104 is attached to the housing 72 all around by an attachment (not shown) so as to cover the accommodation opening 62 and the recovery opening 116. Has been done. The film material 104 and the tip of the partition plate 72F are separated from each other, and the scattered developer G passes between them (see FIG. 1).

In this configuration, the scattered developer G is discharged from the accommodating opening 62 to one side in the width direction of the apparatus and hits the film material 104. Then, the developer G that hits the film material 104 passes between the film material 104 and the partition plate 72F, and is recovered from the recovery opening 116 to the developer recovery section 110 (see the arrow in FIG. 1). That is, the scattered developer G flows from the accommodating opening 62 to the developer recovery unit 110 while changing the flow direction.

-Dust collector 106-
The dust collecting portion 106 is arranged below the connecting portion 114 of the main body portion 102. Specifically, as shown in FIGS. 5A and 5B, the dust collecting unit 106 extends in the depth direction of the device, and has an L-shaped material 120 having an L-shaped cross section and a rectangular plate-shaped filter. It is equipped with 122. The filter 122 is an example of a limiting unit.

As shown in FIG. 2, the L-shaped material 120 includes a plate material 120A constituting the bottom plate of the connecting portion 114 of the main body portion 102 and a plate material 120B overlapping the side plate 102A on one side in the device width direction from the outside of the connecting portion 114. Have. The plate material 120A is an example of a wall. As described above, in the connecting portion 114 of the main body portion 102, the region surrounded by the partition plate 72G, the pair of side plates 102A, and the plate material 120A is designated as the developer recovery portion 110.

As shown in FIGS. 5A and 5B, the plate member 120A extends in the depth direction of the device, and the plate surface faces in the vertical direction. Further, the plate material 120A is formed with a plurality of penetrating portions 124 penetrating the front and back surfaces. The penetrating portion 124 has a rectangular shape extending in the depth direction of the device when viewed from above, and the plurality of penetrating portions 124 are arranged in the depth direction of the device. That is, the plurality of penetrating portions 124 are arranged in the same direction as the direction in which the developer collecting portion 110 extends (device depth direction).

The filter 122 is arranged so as to cover the plurality of penetrating portions 124 formed in the plate material 120A from above (from the developer recovery portion 110 side). The filter 122 limits and captures the passage of the developer G and allows the passage of air.

Further, a double-sided tape (an example of mounting means) (not shown) is attached to the tip portions of the plate material 120B of the L-shaped material 120 and the plate material 120A of the L-shaped material 120, and the dust collecting portion 106 is attached by the double-sided tape. Is attached to the lower end portion of the connecting portion 114.

(others)
As shown in FIGS. 7 and 8, the image forming apparatus 10 includes a substrate apparatus 22 including a plurality of substrates on which integrated circuits and the like are mounted, and a fan 24. The fan 24 is an example of an air flow generating member.

The substrate device 22 is arranged below the developing device 40 with a gap from the developing device 40, and has a rectangular parallelepiped shape extending in the depth direction of the device. When the image forming apparatus 10 is in operation, a current flows through the integrated circuit or the like, and the substrate apparatus 22 generates heat.

The fan 24 is arranged on the front side in the depth direction of the device with respect to the developing device 40 and the substrate device 22. Then, by operating the fan 24, air flows along the upper surface of the plate material 120A of the dust collecting portion 106 and the substrate device 22 (see the arrow in FIG. 7).

(Action of main part composition)
Next, the operations of the developing device 40 and the fan 24 will be described.
When the image forming apparatus 10 is operated, inside the housing 72 of the developing apparatus 40 shown in FIG. 3, the rotating supply auger 66 and the stirring auger 68 have a supply path 72C and a stirring path 72D while stirring the developer G. Circulate between. Specifically, the rotating supply auger 66 and the stirring auger 68 pass the developer G to the supply path 72C through the communication path on the front side in the device depth direction of the supply path 72C and the communication path on the back side in the device depth direction. It is circulated to and from the stirring path 72D. When the developer G is agitated, the toner T in the developer G and the carrier C rub against each other, and the toner T is triboelectrically charged to a predetermined polarity.

Then, the rotating supply auger 66 supplies the developer G to the developing roll 60. The developer G supplied to the developing roll 60 is held in a state where a magnetic brush (not shown) is formed on the surface of the developing roll 60 by the magnetic force of the magnet roll 60A. Then, the rotating sleeve 60B conveys the developer G.

As the sleeve 60B rotates, an air flow (air flow) is generated around the developing roll 60 from the upstream side to the downstream side in the roll rotation direction. Due to this air flow, the developer G scattered from the magnetic brush having a weak friction zone power tends to flow to the downstream edge opening 78 side through between the developing roll 60 and the photoconductor drum 36. Further, when the developer G is circulated between the supply path 72C and the stirring path 72D, the waviness of the surface of the developer G becomes large at the portion where the transport direction of the developer G changes. Therefore, in the developer accommodating portion 74 and the rotating body accommodating portion 72B, the amount of the developing agent G scattered increases in the front side portion and the back side portion in the depth direction of the apparatus. The scattered developer G here includes both a mixture of toner T and magnetic carrier particles and a case where only toner T is used.

Here, as shown in FIG. 1, accommodation openings 62 for connecting the rotating body accommodating portion 72B to the outside of the rotating body accommodating portion 72B are formed at both ends of the rotating body accommodating portion 72B in the depth direction of the device. .. Further, the passage width of the narrowest portion of the developer passage 80 (L1 in the figure) is wider than the opening width of the downstream edge opening 78 (L2 in the figure). Therefore, the air pressure in the developer passage 80 is lower than the air pressure in the downstream edge opening 78.

As a result, at both ends of the rotating body accommodating portion 72B in the depth direction of the device, the air generated around the developing roll 60 (scattered developing agent G) is not on the downstream edge opening 78 side, but on the developing agent passage 80. Flows (guided) to the side. That is, the scattered developer G flows to the developer passage 80 side. If the accommodation opening 62 is not formed, the scattered developer G is discharged to the outside from the downstream edge opening 78.

Then, a part of the scattered developer G is discharged from the accommodating opening 62 to one side in the width direction of the apparatus by the air flow, and hits the film material 104. Further, the developer G that hits the film material 104 passes between the film material 104 and the partition plate 72F, and flows from the recovery opening 116 to the developer recovery section 110 at the end 112 (see the arrow in FIG. 1). ). In this way, the scattered developer G flows to the developer recovery unit 110 at the end 112 while changing the flow direction.

Further, as shown in FIG. 7, the developer G flowing to the developer recovery unit 110 of the end portion 112 hits the bottom plate 102B of the end portion 112 by the air flow, and is centered in the longitudinal direction of the developer recovery unit 110. It flows to the side part (see the arrow in FIG. 7). That is, the scattered developer G flows from both ends in the depth direction of the apparatus to the central portion in the longitudinal direction of the developer recovery unit 110. In this way, the scattered developer G flows from both sides in the depth direction of the apparatus to the developer recovery unit 110 of the connecting unit 114 while changing the flow direction. Then, the developer G that has flowed to the developer recovery unit 110 of the connecting unit 114 stays in the developer recovery unit 110 of the connecting unit 114. In this way, the developer recovery unit 110 recovers the scattered developer G.

Further, when the image forming apparatus 10 is operated, the fan 24 shown in FIG. 7 is operated. When the fan 24 operates, air flows between the developing device 40 and the substrate device 22 from the front side to the back side in the depth direction of the device (see the arrow in FIG. 7). Specifically, when the fan 24 is operated, air flows along the plate material 120A of the dust collecting portion 106 and the upper surface of the substrate device 22.

As a result, the vicinity of the plate material 120A of the dust collecting unit 106 becomes a negative pressure, and the amount of air discharged from the developer collecting unit 110 to the outside through the filter 122 of the dust collecting unit 106 increases. On the other hand, the filter 122 restricts the passage of the developer G and captures the scattered developer G. Further, the substrate device 22 is cooled by the air flow generated by the operation of the fan 24.

(summary)
As described above, the rotating body accommodating portion 72B is placed on the downstream side of the opening 72A and on the upstream side of the agent surface S1 of the developing agent G of the developing agent accommodating portion 74 in the roll rotation direction. A housing opening 62 connected to the outside is formed (see FIG. 1). Therefore, as compared with the case where the rotating body accommodating portion 72B of the portion downstream of the opening 72A and the portion upstream of the agent surface S1 of the developer G of the developer accommodating portion 74 in the roll rotation direction is closed. , Discharge of the scattered developer G from the downstream edge opening 78 is suppressed.

Further, the passage width L1 of the narrowest portion of the developer passage 80 is wider than the opening width L2 of the downstream edge opening 78. As a result, the air flow generated around the developing roll 60 is guided to the developing agent passage 80 side instead of the downstream edge opening 78 side. Therefore, the discharge of the scattered developer G from the downstream edge opening 78 is suppressed as compared with the case where the passage width L1 is narrower than the opening width L2 of the downstream edge opening 78.

Further, the developer collecting unit 110 collects the scattered developer G discharged to the outside from the rotating body accommodating unit 72B through the accommodating opening 62.

Further, as described above, the amount of the developer G scattered at both ends of the rotating body accommodating portion 72B increases in the depth direction of the apparatus. The accommodating openings 62 are formed at both ends of the rotating body accommodating portion 72B in the depth direction of the device. Therefore, in the depth direction of the apparatus, the discharge of the scattered developer G from the downstream edge opening 78 is suppressed as compared with the case where the accommodating opening is formed only in the central portion of the rotating body accommodating portion 72B. ..

Further, the developer recovery unit 110 extends in the depth direction of the device along the developing roll 60. Therefore, for example, as compared with the case where the developer recovery unit 110 extends in a direction different from that of the developing roll 60, the volume of the developer recovery unit 110 is secured in a predetermined amount or more, and then from the depth direction of the apparatus. The area occupied by the developed processor 40 seen becomes smaller (space saving).

Further, when viewed from the depth direction of the apparatus, the developer collecting unit 110 is arranged so as to sandwich at least a part of the developer accommodating unit 74 with the rotating body accommodating unit 72B. Therefore, the volume of the developer recovery unit 110 is predetermined as compared with the case where the developer recovery unit 110 is arranged on the opposite side of the developer storage unit 74 with the rotating body storage unit 72B interposed therebetween. After securing, the area occupied by the developing device 40 in the device width direction becomes smaller (space saving).

Further, the developer collecting unit 110 extends from the position where the accommodating opening 62 is arranged to the central portion side in the longitudinal direction of the developing roll 60 in the depth direction of the apparatus. Therefore, the volume of the developer recovery unit 110 is predetermined as compared with the case where the developer recovery unit 110 extends from the accommodating opening 62 to the side opposite to the central portion side of the rotating body in the depth direction of the apparatus. After securing the above, the area occupied by the developing apparatus 40 when viewed from the radial direction of the developing roll 60 becomes smaller (space saving).

Further, a penetrating portion 124 is formed in the plate material 120A extending in the depth direction of the device, and a filter 122 is attached to the penetrating portion 124. Therefore, the area of the penetrating portion 124 to which the filter 122 is attached becomes larger than that in the case where the penetrating portion is formed in the plate material whose plate surface faces the depth direction of the device. This reduces the frequency of replacement of the filter 122.

Further, as the area of the penetrating portion 124 to which the filter 122 is attached becomes large, a large amount of the scattered developer G is captured by the filter 122.

Further, the dust collecting portion 106 including the filter 122 is attached to the lower end portion of the connecting portion 114 by double-sided tape. Therefore, for example, the dust collecting portion 106 is easily replaced as compared with the case where the dust collecting portion is attached to the connecting portion by welding or the like.

Further, when viewed from the depth direction of the apparatus, the developer collecting unit 110 is arranged so as not to protrude from the rotating body accommodating unit 72B toward the transport path 28 side of the sheet member P. Therefore, it is possible to prevent the developer collecting unit 110 from obstructing the transport of the sheet member P.

Further, the scattered developer G is discharged from the accommodation opening 62 to one side in the width direction of the apparatus and hits the film material 104. Then, the scattered developer G that hits the film material 104 passes between the film material 104 and the partition plate 72F, and flows from the recovery opening 116 to the developer recovery section 110 at the end 112 (FIG. 1). See arrow). As described above, when the scattered developer G hits the film material 104, the toner particles adhere to the film material 104.

Further, the scattered developer G that has flowed to the developer recovery unit 110 of the end portion 112 hits the bottom plate 102B of the end portion 112 and flows to the developer recovery unit 110 of the connecting portion 114 (see the arrow in FIG. 7). As described above, the scattered developer G hits the bottom plate 102B, so that the toner particles adhere to the bottom plate 102B.

Further, in the image forming apparatus 10, by providing the developing apparatus 40, it is possible to prevent the developer G scattered from adhering to the sheet member P conveyed along the conveying path 28.

Further, in the image forming apparatus 10, air flows along the plate material 120A of the dust collecting portion 106 due to the operation of the fan 24. As a result, the vicinity of the plate material 120A of the dust collecting portion 106 becomes a negative pressure, and the filter 122 captures the scattered developer G. That is, the filter 122 captures a larger amount of the developer G than in the case where there is no air flow along the plate 120A.

Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments can be taken within the scope of the present invention. That is clear to those skilled in the art. For example, in the above embodiment, the passage width L1 of the narrowest portion of the developer passage 80 is wider than the opening width L2 of the downstream edge opening 78, but the passage width L1 is compared with the opening width L2. And may be the same or narrower. However, in this case, the effect of the passage width L1 being wider than the opening width L2 is not exerted.

Further, in the above embodiment, the accommodating opening 62 connects both ends of the rotating body accommodating portion 72B to the outside of the rotating body accommodating portion 72B in the device depth direction, but the accommodating opening rotates in the device depth direction. The entire body accommodating portion may be connected to the outside, or may be one end portion.

Further, in the above embodiment, the accommodating opening 62 connects both ends of the rotating body accommodating portion 72B to the outside of the rotating body accommodating portion 72B in the device depth direction, but the accommodating opening rotates in the device depth direction. Only the central portion of the body accommodating portion 72B may be connected to the outside. However, in this case, the accommodation opening 62 does not play an effect by connecting both end portions of the rotating body accommodating portion 72B to the outside of the rotating body accommodating portion 72B in the depth direction of the device.

Further, in the above embodiment, the opening width L2 (see FIG. 1) of the downstream edge opening 78 is the distance between the downstream edge 76 in the roll rotation direction in the opening 72A and the photoconductor drum 36. As shown in FIG. 10, when the member 140 that narrows the distance from the photoconductor drum 36 is attached to the edge portion 76, the opening width L2 is the distance between the member 140 and the photoconductor drum 36. Become.

Further, in the above embodiment, the developer collecting unit 110 is arranged so as to sandwich a part of the developer accommodating unit 74 with the rotating body accommodating unit 72B when viewed from the depth direction of the apparatus. The unit 110 may be arranged so as to sandwich the entire developer accommodating unit 74 with the rotating body accommodating unit 72B when viewed from the depth direction of the device.

Further, although not particularly described in the above embodiment, the housing 72 may be composed of a plurality of members.

Further, in the above embodiment, the present embodiment has been described by the image forming apparatus 10 that directly transfers an image from the photoconductor drum 36 to the sheet member P by using the one-color developer G. It may be an image forming apparatus using the above, or it may be an image forming apparatus that transfers an image from a photoconductor drum to an intermediate transfer.

10 Image forming device 24 Fan (air flow generating member)
36 Photoreceptor drum (an example of an image holder)
40 Developing device 44 Transfer roll (an example of transfer device)
60 Develop roll (an example of a rotating body)
62 Storage opening 72 Housing 72A Opening 72B Rotating body storage 74 Developer storage 76 Edge 78 Downstream edge opening 80 Developer passage 110 Developer recovery 116 Recovery opening 120A Plate material (example of wall)
122 filter (example of limiting part)
124 Penetration G Developer L1 Passage width L2 Aperture width

Claims (5)

A rotating body that is placed facing an image holder on which a latent image is formed and that passes a developer to the latent image while rotating.
A developer accommodating portion for accommodating a developer, a rotating body accommodating portion for accommodating the rotating body with a portion of the rotating body facing the image holder exposed from an opening, and rotation of the rotating body. In the direction, the accommodating opening formed on the downstream side with respect to the opening and on the upstream side with respect to the agent surface of the developer accommodating in the developer accommodating portion and connecting the rotating body accommodating portion to the outside. A housing in which a unit and a developer collecting unit for collecting a developer that has passed through the housing opening from the rotating body accommodating unit are formed is provided.
The accommodating openings are formed only at both ends of the rotating body accommodating portion in the rotation axis direction of the rotating body.
The developer collecting portion extends from the accommodating openings formed at both end portions toward the center portion of the rotating body in the direction of the rotation axis.
A penetrating portion is formed on the wall extending in the direction of the rotation axis forming the developer recovery portion.
The penetrating portion is provided with a limiting portion that restricts and captures the passage of the developer and allows the passage of air.
In the rotation axis direction, the penetration portion is arranged between the accommodation openings formed at both ends, and in the rotation axis direction, the penetration portion and the accommodation opening are separated from each other. Device. In the opening, a downstream edge opening for connecting the rotating body accommodating portion to the outside is formed between the edge portion on the downstream side in the rotation direction of the rotating body and the image holder.
Development in which the developer discharged from the accommodating opening passes between the housing and the rotating body in the portion downstream of the accommodating opening on the downstream side of the downstream edge opening in the rotational direction. A drug passage is formed,
The developing apparatus according to claim 1, wherein the passage width of the narrowest portion in the developing agent passage when viewed from the rotation axis direction of the rotating body is wider than the opening width of the downstream edge opening. According to claim 1 or 2 , the developer recovery unit is arranged so as to sandwich at least a part of the developer accommodating unit between the developer accommodating unit and the rotating body accommodating unit when viewed from the rotation axis direction of the rotating body. The developing device described. An image holder that holds a latent image and an image holder
The developing apparatus according to any one of claims 1 to 3 , wherein the latent image is developed as a developing agent image with a developing agent.
A transfer device that transfers the developer image to the transfer target,
An image forming apparatus. The developer recovery unit of the developing device extends in the rotation axis direction of the rotating body.
The penetrating portion is formed on the wall extending in the direction of the rotation axis constituting the developer collecting portion.
The penetrating portion is provided with the restricting portion that restricts the passage of the developer and traps it, and allows the passage of air.
The image forming apparatus according to claim 4 , further comprising an air flow generating member that generates an air flow so that air flows along the wall of the developing device.

Images