JPH03288876A - Developing device - Google Patents

Abstract

PURPOSE:To reduce the number of parts, to simplify the constitution of the whole of a device and to reduce the cost of manufacture and the occurring rate of a fault by using a bristle width regulating plate also as a cleaning member. CONSTITUTION:By moving at least one of regulating members 14 and 15 which are positioned on both ends of a magnet roll 10 and which regulate the forming area of a magnetic brush in the shaft direction of a magnet roll 16, foreign matters filling up a gap between a sleeve 16 and a metalling blade 20 are eliminated. Simultaneously, by stopping the members 14 and 15 at a prescribed position, the forming area of the magnetic brush can be changed. As the result, the bristle width regulating plates 14 and 15 can be also used as the cleaning member. Thus, the number of the parts is reduced and the constitution of the whole of the device is simplified. Besides, the cost of the manufacture and the occurring rate of the fault are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Fields] This invention is applicable to static electricity 2. The present invention relates to a developing device connected to the A-type image recording device=9, and particularly relates to a regulating member for regulating the magnetic brush forming area formed on the sleeve of the magnet roller.

[Prior Art] Section 6 is a developed view of the main parts of a conventional developing device, and FIG. 7 is a sectional view of the main parts of the developing device. In FIG. 6 and FIG. 7, 24 is a front side panicle width regulating plate (hereinafter abbreviated as front side regulating plate), and 25 is a back side panicle width regulating plate (hereinafter abbreviated as back side regulating plate). , these are placed in contact with or close to the sleeve 26 to prevent the formation of magnetic brushes on the surface of the sleeve 26. The front regulation plate 24 is driven by a solenoid 27 that is turned ON/OFF in response to a development width switching signal, and is held so as to be able to reciprocate in the direction of the arrow. Further, the rear side regulating plate 25 is held in a fixed state. 28 is a metal ring blade,
This is to regulate the thickness of the magnetic brush layer on the sleeve 26. A cleaning member 29 is used to remove foreign matter between the sleeve 26 and the metering blade 28. This cleaning member 29 is held by a holder 30. The holder 30 is supported along a shaft 31 so as to be able to reciprocate.

Both ends of this holder 30 are coupled to a rotating shaft of a reciprocating drive motor 32 via a wire 33.

Therefore, when the motor 32 is rotated, its driving force is transmitted to the holder 30 via the wire 33.

Thus, the cleaning member 29 reciprocates between the sleeve 26 and the metering blade 28 to remove foreign matter.

[Problems to be Solved by the Invention] In the above-mentioned conventional device, the panicle width regulating means and the cleaning means were provided separately, so the structure of the entire device was complicated, which increased the manufacturing cost and failure rate. It became.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a developing device that has a small number of parts, has a compact overall structure, and has low manufacturing costs and a low failure rate.

[Means for Solving the Three Problems] In order to solve the above-mentioned problems and achieve the objectives, the present invention has taken the following measures as basic means.

By moving at least one of the regulating members located at both ends of the magnet roll and regulating the magnetic brush forming area in the axial direction of the magnet roll, foreign matter stuck between the sleeve and the metering blade can be removed and removed at the same time. By stopping the regulating member at a predetermined position, the magnetic brush forming area can be changed.

[Effects] As a result of taking the above measures, the following effects occur. Since the panicle width regulating plate also serves as a cleaning member, the number of parts is small, the overall structure of the device is simple, and the manufacturing cost and failure rate are low.

[Embodiment] FIGS. 1 to 3 are diagrams showing a first embodiment of the present invention, and FIG. 1 shows a schematic configuration of an electrostatic recording type image forming apparatus to which a developing device of the present invention is applied. FIG.

In FIG. 1, 1 is a paper feed tray, and paper 4 is sent out from this paper feed tray by a paper feed roller 2.
The conveyance roller 3 sends the image to a transfer/fixing section 7 formed by a dielectric drum 5 and a transfer roller 6 . Transfer fixing section 7
The paper 4 that has passed through is transferred to a paper ejection tray 9 by a paper ejection roller 8.
is discharged.

On the other hand, the electrostatic latent image formed on the dielectric drum 5 by the recording head 0 is visualized by the developing device 11, and transferred and fixed onto the paper 4 by the transfer fixing section 7.

The residual toner on the dielectric drum 5 that has passed through the transfer fixing section 7 is removed by a cleaning means 12 using a blade. Further, residual charges are removed by the eraser 13.

FIG. 2 is a developed view of the main parts of the developing device in this embodiment shown in FIG. 1, and FIG. 3 is a sectional view of the main parts of the developing device.

In Figures 2 and 3, 14 is a front regulation plate;
Reference numeral 5 denotes a rear regulating plate, which is placed in contact with or close to the sleeve 16 to prevent a magnetic brush from being formed on the sleeve 16.

The front regulation plate 14 is held in a removable state by the holder 17! , 1f has been done. Holder 17 is Nyaft 18
It is supported so that it can be moved back and forth along. Both ends of the holder 17 are connected to a reciprocating drive motor I via a wire 21.
9 is connected to the rotating shaft 19a. Reference numeral 20 denotes a metering blade, which regulates the thickness of the magnetic brush layer on the sleeve 16.

Therefore, when the motor 19 is rotated now, its driving force is transmitted to the holder 17 via the wire 2I. Therefore, the front regulating plate 14 held by the holder I7 reciprocates to remove foreign matter between the sleeve 16 and the metering blade 20 regulating the thickness of the magnetic brush layer. After the foreign matter removal operation is completed, when the front regulating plate 14 is stopped at a predetermined position, that position becomes a position that separates the magnetic brush formation area and non-formation area. In other words, the formation area of the magnetic brush is changed and determined.

The front regulating plate 14 is positioned at a predetermined position by the motor 1.
This is done by controlling the rotation time of 9. That is, when the motor 19 is rotated forward, the front regulation plate (
4 moves in the direction of the rear regulating plate 15. Then, when the wire 2j comes into contact with the rear regulation plate 15, the wire 2j and the rotating shaft 1
9a slips, and the front regulating plate 14 stops at that position. Next, when the motor 19 is reversed,
The front regulating plate 14 moves in the opposite direction. When the motor 19 is stopped after a predetermined time has elapsed, the front regulation plate 14 will stop at a predetermined position.

In this embodiment, the positioning of the regulating plate 14 is performed using the motor 19.
Since the rotation time is controlled based on the rotation time, the stop position of the regulating plate can be set to any plurality of positions such as R+ and D2 without increasing the number of parts.

FIG. 4 is a developed view of a main part of a developing device according to a second embodiment of the present invention, and FIG. 5 is a sectional view of a main part of the developing device. The difference between this embodiment and the first embodiment shown in FIGS. 2 and 3 is that anti-moon and
The point is that position detection means using an I-type sensor is adopted.

As shown in FIGS. 4 and 5, the regulating plate 14 can be attached and removed.
] The holder 22 currently held has a protrusion 22a on its upper part. A reflective sensor 23 is installed at a predetermined location on the movement path of the holder 22 . Thus the holder 22
When the motor moves in the direction of arrow A, the convex portion 22a is detected by the opposite type sensor 23, and the rotation of the motor 19 is stopped. By doing so, the regulation plate 14 can be stopped at a predetermined position.

In this embodiment, since position detecting means using the reflective sensor 23 is employed as the means for positioning the regulating plate 14, the regulating plate 14 can be stopped at a desired position extremely accurately.

Note that the present invention is not limited to the above embodiments,
Of course, various modifications can be made without departing from the spirit of the invention.

[Effects of the Invention] According to the present invention, since the panicle width regulating plate also serves as a cleaning member, it is possible to provide a developing device with a small number of parts, a simple structure of the entire device, and a low manufacturing cost and failure rate. Can be provided.

[Brief explanation of drawings]

Figures 1 to 3 are diagrams showing a first embodiment of the present invention.
The figure is a side view showing the schematic configuration of both electrostatic recording type image forming apparatuses to which the developing device of the present invention is applied, and FIG. 2 is a developed view of the main parts of the developing device in this embodiment shown in FIG. FIG. 3 is a sectional view of essential parts of the developing device. FIG. 4 is a developed view of a main part of a developing device according to a second embodiment of the present invention, and FIG. 5 is a sectional view of a main part of the developing device. FIG. 6 is a developed view of the main parts of a conventional developing device, and FIG. 7 is a sectional view of the main parts of the conventional developing device. 1.1... Developing device, 14... Front side widening regulation plate,
15... Back side panicle width regulating plate, 16... Sleeve, 17
... Holder, 18... Shaft, 19... Reciprocating drive motor, 19a... Rotating shaft, 20... Metering blade, 21... Wire, 22... Holder, 2
2a...Convex portion, 23...Reverse pull type sensor.

Claims (3)

[Claims] (1) In a developing device that has a magnet roll that forms a magnetic brush and a pair of regulating members that regulate the width of the magnetic brush at both ends of the magnet roll, at least one regulating member has a height between the surface of the magnet roll and the height of the magnetic brush. A thin plate that can be inserted between the metering blade and the metering blade that regulates the thickness of the magnetic roll is provided, and at the start of the developing operation, the regulating member is moved back and forth in the axial direction of the magnetic roll together with the thin plate, and then stopped at a predetermined position. A developing device characterized by: (2) The developing device according to claim 1, wherein the means for positioning the movable regulating member to a predetermined position controls the rotation time of a motor that drives the regulating member. (3) As means for positioning the movable regulating member to a predetermined position, the rotation and stopping of the regulating member drive motor is controlled by the output of a sensor that detects the position of the regulating member or a member that moves in conjunction with the regulating member. The developing device according to claim 1, wherein the developing device is controlled.