JP4576957B2 - Developing device and image forming apparatus using the same - Google Patents

Description

  The present invention relates to a developing device used in an image forming apparatus such as a copying machine or a printer, and more particularly to a contact developing device using a non-magnetic one-component developer and an image forming apparatus using the same.

  As a developing device used in a conventional image forming apparatus such as an electrophotographic method, a one-component developing method using a one-component developer consisting only of toner and a two-component developing method using a two-component developer consisting of toner and carrier. It is known. Among them, the one-component development type developing device does not require mixing with the carrier, stirring, and toner concentration control, so that the device can be reduced in size and cost, and further, the developer can be replaced. Since it is unnecessary, it is increasingly used mainly in printers that require maintenance-free operation.

  Further, as a development method employing the one-component development method, development is performed in a development region of a photosensitive member carrying an electrostatic latent image and a development roll carrying and transporting toner (developer) separated from each other. There is a contact development method in which development is performed in contact with the contact development method, and the contact development method is selected in order to obtain good image quality.

  In a developing device employing such a contact development system, a regulating blade constituted by a plate material such as a metal plate having elasticity or silicone rubber is usually applied to an elastic developing roll made of conductive rubber such as silicone rubber or urethane rubber. The toner layer thickness is regulated by the regulation blade, and a toner thin layer charged to a predetermined charge amount is formed on the developing roll. At this time, the developing roll is lightly pressed against the photoconductor by an urging force of a spring or the like, and the charged toner is transferred to the electrostatic latent image on the photoconductor by the action based on the electric field between the photoconductor and the developing roll. It comes to adhere to the image part.

In such a contact development method, there is a demand for sufficiently large peripheral speed difference between the photoconductor and the developing roll in order to supply sufficient toner to the photoconductor. However, when such a large peripheral speed difference is provided, when the pressure contact force between the photoconductor and the developing roll is large, a toner image on the photoconductor that is once developed and visualized at the contact portion (development area) of each other is obtained. Then it will be disturbed. When the pressure contact force is even greater, a mechanical rubbing force other than an electric field acts on the toner adhering to the photosensitive member, causing toner adhering to the non-image area, which leads to a so-called fog phenomenon.
For this reason, in the contact development method, it is desirable that the contact between the photoreceptor and the developing roll is as soft as possible.

In response to such a request, a method using a cylindrical thin film member as a surface layer of the developing roll has been proposed (for example, see Patent Documents 1 and 2).
In Patent Document 1, as shown in FIGS. 8A and 8B, a cylindrical thin film member 103 having a longer peripheral length than the driving roll 102 is disposed on the surface of the driving roll 102 that is rotationally driven as the developing roll 101. In order to press the cylindrical thin film member 103 against the circumferential surface of the driving roll 102, the elastic pad 104 is pressed from the outside or the pressure roller 105 is pressed to increase the frictional force between the driving roll 102 and the cylindrical thin film member 103. A method of rotating the cylindrical thin film member 103 by rotating the drive roll 102 is proposed.
Further, in Patent Document 2, as shown in FIG. 9, the developing roll 101 includes a driven roll 106 and a cylindrical thin film member 103, and a driving roller and a driven roll 106 positioned at both ends of the toner supply roll 107. A cylindrical thin film member 103 is sandwiched between them. A method is proposed in which the cylindrical roller member 103 rotates by rotating the driving roller by the rotational force of the toner supply roll 107. In the figure, reference numeral 108 denotes a seal member that prevents the toner on the cylindrical thin film member 103 from entering both end portions (portion where the driving rollers are disposed), and reference numeral 109 denotes the toner on the developing roll 101. It is a charge regulating member that regulates charging.
In the methods described in Patent Documents 1 and 2, since a tubular thin film member is used and the tubular thin film member is brought into contact with the photosensitive member, a low contact pressure during development can be realized. Become.

Japanese Patent No. 2586502 (Example, FIGS. 4 and 5) Japanese Patent No. 2856007 (Example, FIG. 1)

However, in the method of Patent Document 1, as shown in FIG. 8, it is necessary to transmit the rotational force of the drive roll 102 to the cylindrical thin film member 103 by strongly pressing the cylindrical thin film member 103 with the elastic pad 104 or the like. Therefore, there is a problem that the driving torque is increased and the cost of the driving system is increased.
On the other hand, in the method of Patent Document 2, as shown in FIG. 9, the cylindrical thin film member 103 is driven by the rotational drive of the toner supply roll 107. The speed is determined, and there is no freedom in selecting an appropriate peripheral speed and rotation direction for stably supplying toner from the toner supply roll 107 to the developing roll 101 side. In particular, between the developing roll 101 and the toner supply roll 107 There is a problem that it is not possible to provide an appropriate peripheral speed difference or to rotate in the opposite direction (Against direction) at the opposite portions.

  The present invention has been made in order to solve the above technical problems, and the developer charge amount and developer amount on the developer carrier are stable, and further, the developer supply member to the developer carrier is stable. It is an object of the present invention to provide a developing device capable of further stabilizing the supply amount of the developer and an image forming apparatus using the developing device.

That is, as a first aspect of the developing device according to the present invention, as shown in FIG. 1A, a rotatable cylindrical thin film member 2 is fixed in a state of being included in the cylindrical thin film member 2. A shape holding member that holds the shape of the cylindrical thin film member 2 so as to be slidable with respect to the cylindrical thin film member 2 that is disposed and rotated, and carries a developer on the surface of the cylindrical thin film member 2 A developer carrier 1 to be conveyed, a developer supply member 4 that is disposed opposite to the developer carrier 1, is rotatably driven, and supplies the developer to the developer carrier 1, and the developer supply member 4, a charge regulating member 5 that is opposed to the downstream side of the developer carrying member 1 in the developer transport direction, is rotatably driven, and regulates the charging of the developer on the developer carrying member 1, and the charge regulating member. the driving force of 5 and a drive transmission means 6 for transmitting to the developer carrying member 1, the form The holding member is one recess spaced from the inner peripheral surface of the cylindrical thin film member 2 at a position facing the charging restriction member 5 is characterized that you have provided.
In the present invention, the driving force of the charge regulating member 5 and the driving force of the developer supply member 4 may be driven from different driving sources, for example, driving is transmitted from the same driving source, and the gear A mode in which the rotation direction and speed are appropriately set via a drive transmission member such as the above is also included.

In such technical means, the developing device according to the present application uses a one-component developer, and the developer may be either magnetic or non-magnetic.
Further, the cylindrical thin film member 2 included in the developer carrier 1 may be anything as long as it can carry a developer. For example, a resin tube obtained by adding a conductive agent to a resin such as polyamide resin or fluorine resin, stainless steel, aluminum, or the like. And metal thin plate tubes such as nickel electroformed products. Further, from the viewpoint of effective development, the cylindrical thin film member 2 is disposed opposite to the developer carrier 1 and is in contact with an image carrier (not shown) on which an electrostatic latent image is carried. However, it may be in a non-contact arrangement with the image carrier.

  The charging regulating member 5 may be either a roll or a belt as long as it is rotatable. However, from the viewpoint of performing stable charging regulation on the developer on the cylindrical thin film member 2, a roll member is preferable. . Furthermore, the developer supply member 4 has only to have a drive system different from that of the developer carrier 1 and can supply the developer, and examples thereof include a rigid roll made of metal or an elastic roll.

The drive transmission means 6 in the present invention transmits the driving force of the charge regulating member 5 to the developer carrier 1 and corresponds to the both end portions of the cylindrical thin film member 2 outside the both ends of the shape holding member. And a support member 3 that supports a part of the tubular thin film member 2 so as to press the tubular thin film member 2 from the inner surface, and is provided at a position facing the support member 3 and the tubular thin film member 2. And a driving pressing member 6a that presses the cylindrical thin film member 2 with the rotation axis of the charging regulating member 5 as a core material. The cylindrical thin film member 2 is rotated by the rotation of the driving pressing member 6a accompanying the rotation of the charging regulating member 5. Can be rotated . At this time, the support member 3 may be fixedly arranged, or may be driven and rotated. In addition, in the aspect in which the support member 3 is fixedly arranged, it is preferable that the support member 3 is excellent in slidability with the cylindrical thin film member 2.

  In the present invention, since the driving of the cylindrical thin film member 2 of the developer carrier 1 is transmitted from the charge regulating member 5 side, the rotation direction of the developer carrier 1 and the developer supply member 4 is set to the Against direction. The developer supply amount can be further stabilized by adjusting the gap between the developer carrier 1 and the developer supply member 4, particularly when the developer carrier 1 and the developer supply member 4 are spaced apart from each other. become.

Further, the second aspect of the developing device according to the present invention may be as follows. That is, as shown in FIG. 1B, the tubular thin film member 2 that can freely rotate and the tubular thin film member 2 that is fixedly disposed and rotated in the state of being included in the tubular thin film member 2 are slid. A developer holding body 1 that has a shape holding member that holds the shape of the tubular thin film member 2 and is movable, and carries the developer on the surface of the tubular thin film member 2, and the developer carrying body. The developer supply member 4 is driven separately from the developer carrier 1 so as to be opposed to the developer carrier 1 and supplies the developer to the developer carrier 1, and the developer carrier 1 is developed by the developer supply member 4. A charging regulating member 5 that is disposed opposite to the downstream side in the developer conveying direction and regulates the charging of the developer on the developer carrying body 1, and is arranged opposed to the developer carrying body 1 on the upstream side of the developer supplying member 4. The developer collecting member 7 for collecting the developer on the developer carrying member 1 and the developer And a drive transmission means 6 for transmitting the driving force of the yield member 7 to the developer carrying member 1, the shape retaining member, separated from the inner peripheral surface of the cylindrical thin film member 2 at a position facing the charging regulation member 5 It characterized that you have recesses provided.

In this second aspect, the charge regulating member 5 may be either a roll shape or a blade shape, and the drive transmission means 6 is provided at both end portions of the cylindrical thin film member 2 outside the both ends of the shape holding member. A support member 3 that is provided correspondingly and supports a part of the tubular thin film member 2 so as to press the tubular thin film member 2 from the inner surface, and a position facing the support member 3 with the tubular thin film member 2 interposed therebetween. the and the rotation axis of the developer collecting member 7 is provided with driving the pressing member 6a for pressing the cylindrical film member 2 as a core material (see FIG. 1 (a)), has, in the rotation of the developer collecting member 7 The cylindrical thin film member 2 may be rotated by the accompanying rotation of the driving pressing member 6a. At this time, the support member 3 may be a fixed arrangement as in the first aspect described above. Alternatively, it may be driven and rotated.

And in the 1st aspect and 2nd aspect in this invention, the cylindrical thin film member 2 contains the shape holding member which hold | maintains the shape of the cylindrical thin film member 2, and the cylindrical thin film member 2 is contained. The shape is maintained and the rotation becomes smoother. The shape retaining member is fixedly disposed, so as to slide the tubular film member 2.
Further, if the driving pressing member 6a is provided with an elastic layer at least on the outer peripheral surface thereof, the frictional force between the driving pressing member 6a and the cylindrical thin film member 2 can be improved, and the rotation of the cylindrical thin film member 2 can be improved. Can be further ensured. In addition, an elastic rubber is mentioned as a typical aspect of this elastic layer.
Furthermore, it is preferable that the support member 3 is driven to rotate as the cylindrical thin film member 2 rotates. In this way, the cylindrical thin film member 2 can be rotated more smoothly.

Then, the position shape holding member of the developing device of the present invention is opposed to the charging restriction member 5 is recessed portion separated from the inner peripheral surface of the cylindrical thin film member 2 is provided. By providing this recess in the holding member, a nip between the cylindrical thin film member 2 and the charge regulating member 5 can be formed with certainty, and the charging regulation to the developer can be more reliably performed.

In the present invention, if the cylindrical thin film member 2 is formed of a resin layer containing only an ion conductive substance as a conductive agent, charging regulation with the charging regulating member 5 and image carrier (cylindrical thin film) This is preferable because it makes it easier to control development with the electrostatic latent image held in contact with the member 2. At this time, a mode in which a conductive layer is provided on the inner peripheral surface of the resin layer containing the ion conductive substance may be used, or in a mode in which the conductive layer is not provided, for example, a mode in which the holding member is a conductor. There is no problem.
The present invention is also directed to an image forming apparatus including the developing device described above.

According to the present invention, the developer carrying member having the cylindrical thin film member that is rotatable and carries the developer on the surface is rotated by transmitting the driving force of the charge regulating member. The rotation direction and peripheral speed of the carrier and the developer supply member that supplies the developer to the developer carrier can be freely set, and the developer can be stably supplied to the developer carrier. Become.
In addition, since the developer carrying member having the cylindrical thin film member that is rotatable and carries the developer on the surface is rotated by transmitting the driving force of the developer collecting member, the developer carrying member and The rotation direction and peripheral speed of the developer supply member that supplies the developer to the developer carrier can be freely set, and the developer can be stably supplied to the developer carrier.
Further, by using the shape holding member included in the cylindrical thin film member as the developer carrying member, the shape of the cylindrical thin film member is held and the rotation thereof is made smoother. Further, by providing the shape holding member with a concave portion that is separated from the inner peripheral surface of the cylindrical thin film member at a position facing the charge regulating member, charging regulation to the developer is further stabilized.
Therefore, it is possible to provide a developing device that is small in size and has stable development characteristics over a long period of time.
Further, by using this developing device, it is possible to provide an image forming apparatus capable of stable image formation over a long period of time.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
Embodiment 1
FIG. 2 shows an image forming apparatus according to the first embodiment to which the present invention is applied.
In the figure, reference numeral 21 denotes a photoconductor that carries an electrostatic latent image made of an organic photoconductor rotating in the direction of the arrow. The photoconductor 21 is charged by a charging device 22 such as a scorotron, and a laser writing device. The electrostatic latent image is written by the exposure device 23 having an LED array. The electrostatic latent image is formed as a potential image based on the contrast with the high potential portion not exposed to light because the surface potential of the photosensitive member 21 exposed to light decreases.
Further, the developing device 30 accommodates toner, which is a non-magnetic one-component developer, in a developing housing 31 and carries the toner on a developing roll 32 as a developer carrying member. By applying the developing bias, the developing roll 32 is held at an intermediate potential between the high potential portion and the low potential portion of the electrostatic latent image, and the image portion of the electrostatic latent image is developed with the charged toner. It is a thing. Reference numeral 34 denotes a toner supply roll for supplying toner to the developing roll 32.

Further, the transfer device 26 is constituted by, for example, a transfer roll disposed in contact with the photoconductor 21, and applies a transfer bias in a direction in which the toner image on the photoconductor 21 is attracted by a bias power source 27, thereby causing the photoconductor 21 The upper toner image is transferred onto the recording material 28.
The toner remaining on the photoreceptor 21 is removed by, for example, a doctor blade type cleaning device 29.

Further, in the present embodiment, the recording material 28 to which the toner image on the photoconductor 21 is transferred is conveyed to the fixing device 50, and the toner image is fixed to the recording material 28 by the fixing device 50.
The fixing device 50 has, for example, a heat roll method, and includes a heating roll 51 and a pressure roll 52. By passing the recording material 28 between the heating roll 51 and the pressure roll 52, the toner image is recorded. 28 is fixed.

Here, the developing device 30 which is a feature of the present invention will be described in detail with reference to FIG. In the drawing, the developing device 30 has a developing housing 31 that opens toward the photosensitive member 21, and a developing roll 32 is provided at a position facing the opening of the developing housing 31 and facing the photosensitive member 21. It is housed in a rotatable manner.
The developing roll 32 in the present embodiment is fixedly provided with a sliding member 42 that holds the shape of the flexible tube 41 in a flexible tube 41 of polyvinylidene fluoride (PVdF) having a thickness of 100 μm, and A structure in which a ring-shaped support member 43 that presses the flexible tube 41 from the inner surface is provided inside both ends of the flexible tube 41 is employed.

  Behind the developing roll 32, a toner supply roll 34 is disposed at a position separated from the developing roll 32. The toner supply roll 34 in the present embodiment is made of a metal roll such as stainless steel, and a supply bias (not shown) for supplying toner from the toner supply roll 34 to the development roll 32 side is provided between the toner supply roll 34 and the development roll 32. Applied.

  A toner hopper 35 that contains toner is provided behind the toner supply roll 34, and the toner is agitated by the rotation of the agitator 36. The agitator 36 has a structure in which a blade 36b of a resin film such as a polyester film is supported on a plastic shaft 36a, and the toner in the toner hopper 35 is rotated by the rotation of the shaft 36a during the developing operation. In addition, the toner is supplied to the toner supply roll 34 side.

Further, in the present embodiment, the toner charge amount and the toner amount are regulated with respect to the toner layer on the developing roll 32 on the downstream side in the rotation direction of the developing roll 32 from the facing portion of the developing roll 32 and the toner supply roll 34. A charging restriction roll 37 is disposed. The charging regulating roll 37 is made of a metal roll such as stainless steel, and rotates in the Whit direction with respect to the developing roll 32 (rotates in the same direction at the mutually opposing portions) and is in a predetermined amount with respect to the developing roll 32 Is maintained at. Further, a bias power source (not shown) is connected to the shaft of the charge regulating roll 37, and a charging bias for applying an effective charge amount to the toner layer on the developing roll 32 is applied to a portion facing the developing roll 32. It has become so. For this reason, a toner layer in which the toner charge amount and the toner amount are appropriately regulated is formed on the developing roll 32 by the charge regulating roll 37, and the development which is the opposite portion between the photoconductor 21 and the developing roll 32. Stable development is performed in the area.
Reference numeral 38 denotes a toner collecting roll for collecting the toner on the developing roll 32.

Here, in particular, the pressure contact state between the developing roll 32 and the charge regulating roll 37 will be described in detail.
FIG. 4 is a cross-sectional view showing a pressure contact state between the developing roll 32 and the charge regulating roll 37. In the drawing, the developing roll 32 includes a sliding member 42 having conductivity inside a flexible tube 41, and the shape of the flexible tube 41 is held by the sliding member 42. In addition, a concave portion (A portion in the figure) is provided at a position of the sliding member 42 facing the charging regulation roll 37, so that stable pressure contact between the flexible tube 41 of the developing roll 32 and the charging regulation roll 37 is sufficient. A space where the flexible tube 41 can be deformed is secured so as to be secured.
Further, support members 43 are provided at both ends on the inner peripheral surface side of the flexible tube 41 of the developing roll 32, and a charge regulating roll 37 is provided at a position facing the support member 43 with the flexible tube 41 interposed therebetween. A pressing member 44 fixed to the shaft 37a is disposed.

  FIG. 5 shows the sliding member 42 of the developing roll 32 as an axial section. The sliding member 42 is provided with a concave portion (corresponding to a portion A in the drawing) at a position where the sliding member 42 faces the charging regulating roll 37, and the flexible tube 41 that rotates along the outer peripheral surface of the sliding member 42 is located at the concave portion. It is pressed from the charging regulating roll 37 side and can be deformed to the sliding member 42 side. As a result, the contact state between the charge regulating roll 37 and the flexible tube 41 can be further stabilized.

Next, the operation of the developing device 30 according to such an embodiment will be described with reference to FIGS.
The toner stirred by the agitator 36 in the toner hopper 35 is supplied to the toner supply roll 34 side by the rotation of the blade 36b of the agitator 36. The toner carried on the toner supply roll 34 is conveyed along with the rotation of the toner supply roll 34 and reaches a portion facing the developing roll 32. At this time, the toner on the toner supply roll 34 is supplied to the developing roll 32 side due to the mechanical rubbing force between the developing roll 32 and the toner supply roll 34 and the electric field effect due to the supply bias at the facing portion.
At this time, the developing roll 32 and the toner supply roll 34 rotate in the agaist direction, and further, since an appropriate gap is maintained, the toner supply amount from the toner supply roll 34 to the developing roll 32 is stabilized. . For example, if the rotation is in the With direction, the toner supply amount tends to be unstable.

The toner supplied to the developing roll 32 is charged by a charge regulating roll 37, and a thin toner layer having a predetermined toner charge amount and a predetermined toner amount is formed on the developing roll 32.
At this time, the flexible tube 41 and the charge regulating roll 37 of the developing roll 32 are nipped between the flexible tube 41 and the charge regulating roll 37 by the concave portion of the sliding member 42 included in the flexible tube 41. The shape is stabilized, and the toner layer pressure regulation and charging regulation are stably performed.
Then, the toner thin layer regulated on the developing roll 32 is conveyed to the developing area between the developing roll 32 and the photoreceptor 21.
In the development area, development is performed by a development bias from a bias power source 33 (see FIG. 2), and the electrostatic latent image on the photoconductor 21 is visualized. Residual toner that remains without being developed on the developing roll 32 is conveyed as it is on the developing roll 32 and is collected by the toner collecting roll 38.

In the present embodiment, since the flexible tube 41 of the developing roll 32 is driven from the driving of the charge regulating roll 37, the rotation direction of the toner supply roll 34 and the developing roll 32 can be set to the Against direction. Since the peripheral speeds can be set to predetermined speeds, the toner supply from the toner supply roll 34 to the developing roll 32 can be stably performed.
Further, since the flexible tube 41 of the developing roll 32 is rotated by the pressing member 44 fixed to the shaft of the charge regulating roll 37, the rotation of the flexible tube 41 is stabilized and the drive transmission is performed. For example, since a gear or the like is not required, cost increase can be suppressed and downsizing of the apparatus can be promoted.

Further, in the present embodiment, the flexible tube 41 is driven at the position of the charge regulating roll 37, so that the flexible tube 41 is pushed toward the photoreceptor 21 side. For this reason, it is easy to create a gap between the flexible tube 41 of the developing roll 32 and the included sliding member 42 at a portion where the developing roll 32 and the photosensitive member 21 are opposed to each other. Low contact pressure development with a lower contact pressure with 21 can be realized.
Furthermore, since the flexible tube 41 is rotated by the pressing member 44, the flexible tube 41 is pressed against the sliding member 42 between the flexible tube 41 and the toner supply roll 34. The gap between them is stabilized. For this reason, the stress applied to the toner is small and constant, and a stable image quality is maintained over a long period of time.
In the present exemplary embodiment, the developing roll 32 and the toner supply roll 34 are separated from each other. However, the present invention is not limited to this, and the developing roll 32 and the toner supply roll 34 may be in contact with each other.

Embodiment 2
FIG. 6 shows a developing device according to Embodiment 2 of the image forming apparatus to which the present invention is applied.
In this figure, the present embodiment is configured in substantially the same manner as the developing device 30 in the first embodiment, but the rotation of the flexible tube 41 of the developing roll 32 is transmitted from the driving of the toner collecting roll 38. This is different from the first embodiment. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and the detailed description is abbreviate | omitted.

The developing roll 32 in the present embodiment is a flexible tube formed by pressing members (not shown) fixed to both ends of the shaft of the toner recovery roll 38, similarly to the charge regulating roll 37 in the first embodiment. Since 41 is rotated, the support member 43 is disposed so as to contact the inner surface of the flexible tube 41 at a position facing the toner collecting roll 38.
In the present embodiment, since the flexible tube 41 of the developing roll 32 is rotated by the driving force of the toner collecting roll 38, the flexible tube 41 is located at a portion facing the developing roll 32 and the toner supply roll 34. It is pushed to the toner supply roll 34 side. For this reason, it is preferable that the developing roll 32 and the toner supply roll 34 are in contact with each other because fluctuations in the gap between them can be suppressed.

On the other hand, at the portion (development region) where the developing roll 32 and the photosensitive member 21 are opposed, the flexible tube 41 is pulled and comes into close contact with a sliding member 42 (not shown) (see FIG. 4 specifically). The direction of the nip is stable, and the nip shape is stable. In particular, in the case of non-contact development, the gap between the two is stable, which is more preferable.
As in the present embodiment, even when the driving force on the toner collection roll 38 side is used to rotate the flexible tube 41 of the developing roll 32, the flexible tube 41 can be rotated as in the first embodiment. The stress applied to the toner is stable and small and constant, and a stable image quality is maintained for a long time.

  In the present embodiment, the sliding member 42 included in the flexible tube 41 is not provided with a concave portion as in the first embodiment at a portion where the developing roll 32 and the charge regulating roll 37 are opposed to each other. However, as in the first embodiment, for example, a concave portion (see FIG. 5) may be provided, and in this case, the toner charging regulation between the developing roll 32 and the charging regulating roll 37 is further stabilized. To be done.

FIG. 7 shows a developing device as a modification of the present embodiment, in which a sheet-shaped charge regulating blade 39 is used as a charge regulating member instead of the above-described charge regulating roll. There are features.
As described above, the charge regulating blade 39 can be used as the charge regulating member. In this case, the charge regulating blade 39 is supplied onto the developing roll 32 depending on the peripheral speed of the developing roll 32 and the toner supply roll 34, the bias between them, and the like. By optimizing the amount of toner, effective charge regulation can be performed even if the contact pressure of the charge regulation blade 39 is reduced, and toner sticking to the charge regulation blade 39 can be reduced.

(A) (b) is explanatory drawing which shows the outline | summary of the image development apparatus concerning this invention. 1 is an explanatory diagram showing Embodiment 1 of an image forming apparatus to which the present invention is applied. FIG. 2 is an explanatory diagram illustrating a developing device according to the first embodiment. FIG. 3 is an explanatory diagram showing a main part of the first embodiment. FIG. 3 is an explanatory diagram showing an axial cross section of the first embodiment. FIG. 10 is an explanatory diagram illustrating a developing device according to a second embodiment. FIG. 10 is an explanatory view showing a developing device as a modified example of the second embodiment. It is explanatory drawing which shows the developing device as a prior art example. It is explanatory drawing which shows the image development apparatus as another prior art example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Developer carrying body, 2 ... Cylindrical thin film member, 3 ... Support member, 4 ... Developer supply member, 5 ... Charge control member, 6 ... Drive transmission means, 6a ... Drive pressing member, 7 ... Developer collection member

Claims (6)

A cylindrical thin film member that can freely rotate, and a shape holding that holds the shape of the cylindrical thin film member by being slidable with respect to the cylindrical thin film member that is fixedly disposed and enclosed in the cylindrical thin film member. And a developer carrying member that carries and conveys the developer onto the surface of the cylindrical thin film member,
A developer supply member that is disposed opposite the developer carrier, is rotatably driven, and supplies the developer to the developer carrier;
A charge regulating member disposed opposite to the developer carrying member on the downstream side in the developer transport direction from the developer supply member, driven to be rotatable, and for regulating charging of the developer on the developer carrying member;
Drive transmission means for transmitting the driving force of the charge regulating member to the developer carrier,
The shape holding member is provided with a recess that is separated from the inner peripheral surface of the cylindrical thin film member at a position facing the charge regulating member.
It said drive transmission means,
A support member that is provided corresponding to both end portions of the tubular thin film member outside the both ends of the shape holding member and supports a part of the tubular thin film member so as to press the tubular thin film member from the inner surface;
A driving pressing member that is provided at a position facing the support member and the cylindrical thin film member and presses the cylindrical thin film member with the rotation shaft of the charge regulating member as a core material;
A developing device characterized in that the cylindrical thin film member is rotated by the rotation of the driving pressing member accompanying the rotation of the charge regulating member. A cylindrical thin film member that can freely rotate, and a shape holding that holds the shape of the cylindrical thin film member by being slidable with respect to the cylindrical thin film member that is fixedly disposed and enclosed in the cylindrical thin film member. And a developer carrying member that carries and conveys the developer onto the surface of the cylindrical thin film member,
A developer supply member that is disposed opposite the developer carrier, is rotatably driven, and supplies the developer to the developer carrier;
A charge regulating member disposed opposite to the developer carrying member on the downstream side in the developer transport direction from the developer supply member, driven to be rotatable, and for regulating charging of the developer on the developer carrying member;
A developer collecting member that is disposed opposite to the developer carrying member upstream of the developer supply member and collects the developer on the developer carrying member;
Drive transmission means for transmitting the driving force of the developer recovery member to the developer carrier,
The shape holding member is provided with a recess that is separated from the inner peripheral surface of the cylindrical thin film member at a position facing the charge regulating member.
The drive transmission means is
A support member that is provided corresponding to both end portions of the tubular thin film member outside the both ends of the shape holding member and supports a part of the tubular thin film member so as to press the tubular thin film member from the inner surface;
A drive pressing member that is provided at a position facing the support member and the cylindrical thin film member and presses the cylindrical thin film member with the rotation axis of the developer recovery member as a core material;
A developing device characterized in that the cylindrical thin film member is rotated by rotation of the drive pressing member accompanying rotation of the developer recovery member. The developing device according to claim 1 or 2,
The driving pressing member includes an elastic layer on at least an outer peripheral surface thereof. The developing device according to claim 1 or 2,
The developing device according to claim 1, wherein the supporting member is driven to rotate as the cylindrical thin film member rotates. The developing device according to claim 1 or 2,
The cylindrical thin film member is constituted by a resin layer containing only an ion conductive substance as a conductive agent. An image forming apparatus comprising the developing device according to any one of claims 1 to 5.

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