JPS59177578A - Dry type developing device - Google Patents

Abstract

PURPOSE:To prevent effectively various trouble originating from a toner scatter by covering a gap part between the front surface and a developing unit photosensitive body with the 1st toner scatter preventing body which is formed detachably and a gap part between a flank and the photosensitive body with the 2nd toner scatter preventing body. CONSTITUTION:There is a large gap between the opening part 114 of a casing 102 and the photosensitive body 16 before a toner scatter preventing body 150 is attached to the casing 102, but this gap is almost sealed after the toner scatter preventing body 150 is attached. Namely, the front end of the flexible member 154 of the toner scatter preventing body 150 adjoins to or contacts slightly the surface of the photosensitive body 16. The 2nd toner scatter preventing body 180, on the other hand, is attached to the casing 102 together with a side wall 126 when the side wall 126 is attached. Namely, the toner scatter preventing body 180 is attached to the side wall 126 in both directions of arrows F1 and F3 in figure and the gap of the flank of the casing 102 is almost covered with the toner scatter preventing body 180.

Description

Detailed Description of the Invention Technical Field The present invention relates to a developing device for a recording device such as a copying machine or a printer, and more particularly to an improvement in a dry developing device that develops a latent image using a dry developer. It is.

As is well known, conventional dry developing devices include magnetic brush type,
A cascade type, a fur brush type, a spray type, etc. have been proposed and put into practical use.

FIG. 1 shows an example of a magnetic blank type dry developing device. In this example, a developing unit 12 is provided on the right end side of the cassette receiver 10. A photosensitive member 14 is attached to the cassette receiver IO from the direction of arrow FA in the figure.

In this photoreceptor cassette 14, a belt-like or sheet-like photoreceptor 16 as a latent image carrier is stretched across left and right sets of roller mechanisms 18 and 20. 22 are connected. Photoreceptor cassette 1
4 is attached to the cassette receiver 10, a part of the surface of the photoreceptor 16 comes to face the developing unit 12. Note that a spring mechanism 24 is provided between the roller mechanism 18 and the main body of the photoconductor door 14 to provide tension.

The developing unit 12 is formed in the shape of a hopper, and an opening 30 is provided in a portion of the lower side facing the photoreceptor 16. A portion of the developing sleeve 32 is exposed through the opening 30 and faces the photoreceptor 16. Developing sleeve 32
The height of the magnetic brush formed on the surface of the magnetic brush is regulated by the doctor blade 34. In addition, the developing unit,
A lid portion 36 is provided on the top of the lid portion 36, which is rotatable in the direction of arrow FB, so that developer (hereinafter simply referred to as “toner”) can be replenished.

When mounting the photoreceptor cassette 14, the roller mechanism 18
．． Twenty bearings 26 and 28 engage positioning pins 40 and 42 of cassette receiver 10, respectively, to ensure a proper development gap between photoreceptor 16 and development sleeve 32. An electrostatic latent image is formed on the surface of the photoreceptor 16 by means not shown, and the developing unit 12
9) A toner is attached and development is performed.

In this developing operation, with respect to the speed of the photoreceptor 16,
The 1-ner is transported at a relative speed of 3 to 7 times so that it contacts or collides with the photoreceptor 16. For this reason, there is a phenomenon in which toner is scattered inside the device when the toner is attacked.

If this scattered toner lands on other parts of the device such as the chart, optical system, etc., it will cause uneven charging and uneven exposure, which in turn will cause abnormal images such as uneven density and uneven background density in the copied image. Become.

Furthermore, if toner adheres to the power supply electrical equipment, drive transmission unit, or other mechanical parts due to the influence of airflow, there is a problem that electrical and mechanical malfunctions and troubles may occur.

In order to prevent such inconveniences, an improved dry developing device as shown in FIG. 2 has been proposed, for example, in Patent Application No. 26371 of 1982. In this figure, the developing unit 50 has a recess 52 formed on the side surface on the side of the door blade 34, and the developing sleeve 32
A magnet 54 is housed inside. In this example, in order to cover the opening 30, a toner scattering prevention body 60 having a substantially S-shaped cross section is engaged with the recess 52. A flexible member 62 and a magnetic body 64 are provided at the tip of the toner scattering prevention body 60, respectively. The flexible member 62 is used to prevent damage to the photoreceptor when the photoreceptor cassette 14 is attached or removed, and the magnetic member 64 absorbs toner due to the magnetic attraction force that acts between it and the magnet 54 in the developing sleeve 32. This is for holding the position of the scattering prevention body 60.

In the improved dry-type developing device as described above, not only is it possible to effectively prevent toner from scattering, but also it is possible to easily attach and detach the photoreceptor force set 14, thereby preventing adverse effects on other functions. sufficient consideration has also been given.

Incidentally, in recent years, devices such as copying machines and printers that use the above-mentioned developing devices have been becoming increasingly smaller.
On the other hand, their functions tend to become increasingly sophisticated and complex. For this reason, there is a strong demand for preventing problems with other functions caused by flying toner in the developing device.

Purpose The present invention has been made in view of the above-mentioned points, and by further advancing the improvement, it is possible to more effectively prevent toner scattering while paying more attention to interference with other device functions. The purpose is to effectively prevent various inconveniences caused by toner scattering.

Configuration The configuration of the present invention will be described below based on one embodiment.

FIG. 3 shows an exploded view of an embodiment of the dry developing device according to the present invention. FIG. 4 shows a state in which a first toner scattering prevention member, which will be described later, is attached to the developing unit, and FIG. 5 shows a view taken from arrow V in FIG. ing. In these FIGS. 3 to 5, the casing 102 of the developing unit 100 is
It is formed in the shape of A lid 104 is provided on the top of the casing 102 so that it can be opened and closed.
The toner 106 can be replenished from there.

A developing sleeve 108 is rotatably provided at a lower portion inside the casing 102 and maintained at an appropriate distance from the inner wall of the casing 102 . Above the inside of the casing 102 is an annotator 110 for stirring the toner 106.
A sensor 112 for detecting increase/decrease of the l-ner 106 is provided at an appropriate position outside the casing 102.

On the other hand, an opening 114 is provided in the lower side surface of the casing 102, and a portion of the developing sleeve 108 is exposed from this opening 114. This opening 114
A doctor blade 116 is attached by a bolt means 116A to a portion of the end of the casing 102 constituting the outer circumferential end of the developing sleeve 108, which is close to the surface of the developing sleeve 108. 108
facing the surface while maintaining a predetermined distance.

This doctor blade 116 is provided along the length of the developing sleeve 108 .

An appropriate number of magnets 118 are inserted into the developing sleeve 108 along its outer periphery in the longitudinal direction. These magnets 118 are arranged so that the polarities are alternately reversed, and brush-like spikes of toner 106 are formed on the outer surface of the developing sleeve 108 by lines of magnetic force generated by the magnets 118 .

First and second passers 120A are provided along the length of the side of the casing 102 on which the doctor blade 116 is provided.

120B are formed respectively, and furthermore, a passer 120A,
A passage groove 122 is formed between the two parts 120B. Each of the passers 120A and 120B is provided with a nut near each end thereof, and a side wall 126 is supported by this nut and a bolt 124. Passeron 120C
.

The same applies to 120D.

The passage groove 122 has an appropriate opening 1 toward the left in FIG.
It has 22A. A rod-shaped member 128 is provided in parallel with the developing sleeve lo8 at a position close to the developing sleeve lo8 in the casing 102, and the height of the magnetic bra is also regulated by this.

In addition, Tsujin 120A, 120B, 120C.

120D or the passage groove 122 may be formed integrally with the casing 102 by die-casting or the like when manufacturing the casing 102, or alternatively, it may be formed separately from the casing 102 and attached to the casing 102 by a bonding means such as an adhesive means or a screw means. 102.

Next, the first toner scattering prevention body 150 attached to the developing unit and the toner ioo will be described.

The toner scattering prevention body 150 has a holding portion 152 whose cross section perpendicular to the longitudinal direction is bent into a substantially S-shape. The S-shaped bending of the holding portion 152 corresponds to the bending of the back surface of the doctor blade 116 with respect to the side surface of the casing 102, and a flexible member 154 is provided at the tip thereof to protrude in the longitudinal direction. .

Furthermore, in this bent part, is there a moon? A relief hole 156 for the root means 116A is correspondingly provided.

On the longitudinal end of the holding part side 152, on the side opposite to the side where the flexible member 154 is provided, the holding part 1 is provided.
58A and 158B are provided respectively. These engaging portions 158A and 158B' have a substantially U-shaped cross section perpendicular to the longitudinal direction.
It can be engaged with a passage groove 122 formed in the casing 102 of.

A magnetic body 16 is disposed on the flexible member 154 in the longitudinal direction.
0 is set. In other words, the flexible member 154 is protruded and held between the holding member 152 and the magnetic body 160.

A convex handle 162 is provided approximately at the longitudinal center of the toner scattering prevention body 150 in contact with the holding member 152 and the magnetic body 160.
is provided. This handle 162 is used for attaching and detaching the toner scattering prevention body 150 to and from the developing unit 1.00. If the handle 162 is formed of a side material such as rubber that has elasticity, it will be deformed by the pressing force of the fingers when the handle 162 is pinched with the fingers, thereby making it easier to attach and detach the handle 162.

In addition, when installing the magnetic body 160 or the handle 162,
In addition to mechanical means such as caulking, adhesive bonding may also be used.

Adhesion has the advantage that the whole can be removed uniformly and the manufacturing process can be simplified.

Next, the second l/ner scattering prevention body 180 will be explained. The second toner scattering prevention body 180 is intended to prevent toner scattering from the side surface, that is, from the front side and the rear side in FIG. The structure is as follows. That is, the toner scattering preventer 180 is bonded to the side wall 126 by adhesive or other method in the direction of arrow F1 in FIG. Note that the rear side of FIG. 3 shows a state in which the side wall 126 and the toner scattering prevention body 180 are combined.

To explain the materials constituting each of the above parts, first, the holding member 152 is made of aluminum, which is a non-magnetic metal, for example.
It is made of brass, resin, etc. Flexible member 154,
For example, it is made of flexible materials such as rubber, sponge, flocked hair, and bran.

Furthermore, the toner scattering prevention body 180 may be formed of a sponge such as Moltono Lane, flexible rubber, or the like, and may have a flocked or plan shape.

Next, the operation of the second embodiment will be explained.

The photoreceptor cassette 14 is attached to the developing unit 100 as shown in FIG.
50 is installed.

That is, the engaging portion 158, A of the toner scattering prevention body 150
, 158. B is engaged with the passage groove 122 through the opening 122A. As a result, the magnetic body 160 comes close to the magnet 118 in the developing sleeve 108 and its magnetic force is applied, so that the sensitive body 234 is attracted to the magnet 118. Due to this magnetic action, the toner scattering prevention body 1
50 will be well maintained in the condition shown in FIG. 4 or FIG.

As shown in FIG. 3, before the toner scattering prevention body 150 is attached to the casing 102, the casing 10
Although there is a considerable gap between the opening 114 of No. 2 and the photoreceptor 16, this gap is almost closed by attaching the toner scattering prevention member 150. That is, the tip of the flexible member 154 of the toner scattering prevention member 150 is connected to the photoreceptor 1.
Close to or slightly in contact with the surface of 6.

On the other hand, the second toner scattering prevention body 180 is attached to the casing 102 together with the side wall 126 when the side wall 126 is attached. That is, the toner scattering prevention body 180 is
The side wall 126 is attached to the casing 1 from the direction of arrow F1 in FIG.
It is installed on 02. As a result, the gap on the side surface of the casing 102 is almost completely sealed by the toner scattering preventer 180.

In this state, the photoconductor cassette 14 is attached and detached, but since the L-ner scattering prevention body 180 is made of a flexible material, damage to the photoconductor 16 caused by attachment and detachment of the photoconductor cassette 14 is prevented. Ru. 6 and 7 show the toner scatter prevention bodies 150 and 180 installed, and FIG. 6 shows the side wall 126 and the toner scatter prevention body 180 as seen through. It is. Note that the cassette receiver 10 shown in FIG. 1 is omitted from FIGS. 3 to 7.

Next, a latent image is formed on the surface of the photoreceptor 16 by known means. The photoreceptor 16 on which the latent image has been formed is sequentially opposed to the developing sleeve 108 by the simultaneous rotation of roller mechanisms 18, 20 (see FIG. 1).

On the other hand, in response to the movement of the photoreceptor 16, the developing sleeve 108
is also rotationally driven, and spikes of toner 106 are formed on its outer surface. The height of the ears of toner 106 is regulated by rod-shaped member 128 and doctor blade 116 . Further, the spikes of toner 106 contact or collide with the photoreceptor 16 as the developing sleeve 1o8 rotates, and adhere to the surface of the photoreceptor 16 corresponding to the latent image.

At this time, some of the toner 106 tries to scatter, but is prevented by the toner scatter preventers 150 and 180 and falls below the casing 102.

When replacing the photoreceptor cassette 14, the above-mentioned installation procedure can be performed in reverse. First, the toner scattering prevention member 150 is removed from the state shown in FIG. 6, and then the photoreceptor force set 14 is replaced. The toner scattering prevention body 150 may be attached to the casing 102 again.

During the above operations, the toner scattering prevention body 150
The photoreceptor cassette 14 is attached to the casing 102.
When the toner scattering prevention member 150 is attached, the surface of the photoreceptor 16 and the toner scattering prevention member 150 come into contact. However, since the tip of the toner scattering prevention member 150 is formed of a flexible member 154, such damage to the photoreceptor 16 is prevented. More specifically, when the photoreceptor force set 14 is attached, the photoreceptor cassette 14 moves in the direction of the inclination of the flexible member 154, so that the contact between the photoreceptor 16 and the flexible member 132 is extremely smooth. , therefore, the photoreceptor 16 is not damaged.

On the other hand, when the IT photoconductor cassette 14 with the toner scattering prevention body 150 attached to the casing 102 is attached and detached, if the attraction force of the magnetic body 160 is relatively weak, the photoconductor cassette 1
4, the toner scattering prevention body 150 is also attached and detached, and the flexible member 132 only comes into smooth contact with the photoreceptor 16. If the attractive force of the magnetic body 160 is relatively strong, the photoreceptor 14 will move in the opposite direction to the direction of the inclination of the flexible member 154. Therefore, photoreceptor 1
6 and the flexible member 154 is not necessarily smooth, and there is a risk of damaging the photoreceptor 16. However, in general, when the photoreceptor cassette 14 is attached and removed, it means that it is time to replace the photoreceptor 16, and in fact, There is no inconvenience at all.

Note that the closer the tip of the flexible member 154 is to the photoreceptor 16, the greater the effect of preventing scattering of the toner 106, and it is preferable that the distance be 0.5 mm or less, or that the tip should be in slight contact with the photoreceptor 16.

Next, another embodiment of the present invention will be described with reference to FIG. 8. The same reference numerals will be used for the same components as in the above-described embodiment, and the explanation thereof will be omitted.

This embodiment differs from the second embodiment in the structure of the developing unit 1 and the first toner scattering prevention body. Developing unit 20
A plurality of magnetic bodies 202 are inserted into the passage groove 122 at appropriate intervals.

The first toner scattering prevention body 250 includes a retaining portion 158A,
Instead of 158B, a convex portion 252 is formed along the longitudinal direction. This convex portion 252 can be fitted into the opening 122A of the passage groove 122. Furthermore, in place of the handle 162, a handle 254 is formed over the entire length of the toner scattering prevention body 250, and a magnet 256 is provided below the handle 254. That is, the convex portion 252 and the magnet 256 are arranged to face each other with the holding member 152 in between.

Next, the operation of the above embodiment will be described. The toner scattering prevention body 250 is attached to the casing 102 as indicated by arrow F4 in FIG. At this time, the convex portion 252
It is fitted into the opening 122A formed in 2. As a result, the magnetic body 202 provided in the passage groove 122 and the magnet 256 provided in the toner scattering prevention member 250
are opposed to each other via the holding member 152, and the toner scattering prevention body 250 is attached and fixed to the casing 102 by the magnetic force of the magnet 256.

Other functions are similar to those of the embodiment described above.

In addition, even if the toner 106 scatters inside the device,
A part of the toner 106 will adhere to the magnet 256 of the toner scattering prevention member 250, so that this also has the effect of preventing the toner 106 from scattering to other parts of the device.

Note that the present invention is not limited to the above-mentioned embodiment, and for example, in the embodiment shown in FIG. 8, the magnet 256 and the magnetic body 202 may be arranged oppositely. Furthermore, the holding member 152 may be made of a magnetic material. In other words, it is arbitrary where the magnets and magnetic material are formed entirely, but as long as the toner scattering prevention member can be maintained in a well-attached state on the developing unit by magnetic force, any arrangement or arrangement may be used.
The shape and configuration are arbitrary.

However, since toner, particularly magnetic toner, is affected by magnetic force, it is necessary to take care not to adversely affect the development of the latent image on the photoreceptor.

For example, the toner 106 attached to the developing sleeve 108
This prevents the formation of a bridge, that is, a chain-like bridge, at the position of the toner scattering prevention bodies 150, 250.

Further, the second toner scattering prevention body may also be configured to be detachable in the same manner as the first toner scattering prevention body, or both toner scattering prevention bodies may be attached and detached in conjunction with each other. .

The second toner scattering prevention body may be provided only on one side of the developing unit, if necessary.

In addition, the toner scattering prevention body has a click,
Noriction etc. may be used.

Furthermore, the magnetic coupling means may utilize not only attractive force but also repulsive force.

In particular, with regard to the shape and arrangement of the toner scattering preventer, it is preferable to consider the relationship between the air flow within the apparatus and the toner scattering, the moving speed of the photosensitive member and the photosensitive sleeve, or the relative speed thereof.

Furthermore, in the above embodiments, the photoreceptor is a skein.

Although the photoreceptor generally has a finite lifespan, it is not limited to the cassette type and can be attached and detached. Therefore, the present invention can be effectively applied to recording apparatuses using other types, for example, drum-shaped photoreceptors.

Furthermore, the present invention is basically applicable not only to the magnetic plan type developing device but also to other types of developing devices.

Effects As described above, according to the present invention, the gap between the developing unit and the photoreceptor is covered by the first toner scattering prevention member that is detachably formed with respect to the developing unit. Since the gap on the side surface is covered by the second toner scattering prevention body, toner scattering is effectively prevented without causing any trouble in attaching and detaching the photoreceptor sumo wrestler yl-, and the main unit functions well for a long period of time. 0, which has an excellent effect of being secured.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an example of a magnetic plano type dry developing device, Fig. 2 is a partially cutaway side view showing an example of an improved conventional dry developing device, and Fig. 3 is a dry type according to the present invention. FIG. 4 is an exploded perspective view showing an embodiment of the developing device. FIG. 4 is a partially cutaway perspective view showing the state in which the first toner scattering prevention member is attached to the developing unit 71. FIG. Side view seen from arrow V, Figure 6 is -
and a partially transparent side view showing a state in which the second toner scattering prevention body is attached, FIG. 7 is a side view showing a state in which the first and second toner scattering prevention bodies are attached, and FIG. FIG. 3 is an exploded perspective view showing another embodiment of the present invention. 14...Photoconductor cassette 16...Photoconductor 100.200...Developing unit, tray 102...Kaizon 106-1-ner 114...Opening 118.256...Magnet 150.250 First Toner scattering prevention body 154...
Flexible Department Publication 160.202... Magnetic material 180 - Second toner scattering prevention body Patent applicant Rico Co., Ltd. Part 1 Figure 2 ■ j4 32 54 Figure 5 +00 08 Figure 6

Claims (1)

[Claims] J. A part of the casing in which the toner is accommodated is provided with an opening, and the toner is supplied from the opening to a latent image carrier that is removably disposed in the vicinity of the opening. In the dry developing device, the device has two toner scattering prevention bodies, a first and a second toner scattering prevention body, and the second toner scattering prevention body is connected to the surface of the latent image carrier and the casing. The second toner scattering prevention body has a shape that covers the open part on the front between the latent image carrier surface and the casing, and can be freely attached to and detached from at least the casing. A dry phenomenon device characterized by having a shape that covers an open end portion. 2. The dry developing device according to claim 1, wherein the first toner scattering prevention member is attached to the casing by magnetic coupling means. 3. In the apparatus according to claim 2, the magnetic coupling means includes a magnetic force generating member located inside the casing for holding the toner and transferring the toner at a position where the toner is transferred to the latent image carrier. and a magnetic member disposed on the toner scattering prevention member and magnetically coupled to the magnetic force generating means. 4. In the apparatus according to claim 1, 2, or 3, a portion of at least one of the first and second toner scattering prevention members close to the latent image carrier is a flexible member. A dry developing device characterized by being formed of.