JPS5912472A - Cleaning blade holder of blade cleaning device - Google Patents

Abstract

PURPOSE:To replace only an elastic cleaning blade by forming a blade attachment groove in the holding member for the cleaning blade and inserting and holding the elastic cleaning blade in the blade attachment groove. CONSTITUTION:The cleaning blade holding member 2 is provided facing the surface 1a of a photoreceptor 1; and the cleaning blade 3 is fitted in the blade holding member 2 and the blade attachment groove 4 is formed facing the photoreceptor surface 1a. Then, the elastic cleaning blade 3 is inserted and held in this blade attachment groove. Consequently, only the cleaning blade is replaced and the cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cleaning blade holding device in a grade cleaning device for cleaning untransferred residual toner on a photoreceptor in an electrophotographic apparatus.

The blade cleaning device scrapes off and removes untransferred residual toner on the photoreceptor by bringing a cleaning blade (hereinafter simply referred to as "grade") into contact with the photoreceptor that serves as an image bearing member, and removes the untransferred residual toner on the photoreceptor by touching the contact line between the blade and the photoreceptor. In a cleaning device using the wiper grade cleaning method (hereinafter referred to as wiper one method), in which the blade is held so that the angle formed between the tangential plane and the blade on the front side in the photoreceptor moving direction is an acute angle, various grades are used. It is held by a holding device.

For example, an elastic blade is used as the first. Insert the second holding means and screw the first. It is known to hold the elastic blade by tightening the second holding means, or to hold the blade in a straight state by bonding an elastic grade to a single holding member.

However, with the former structure, tightening the screw causes the holding member to curve in the longitudinal direction, and with elastic grade tightening, the part contracts and the blade edge retracts, and the thickness of the blade is uneven. ), the linearity of the blade edge will be poor due to reasons such as the inability to absorb it.If the latter structure is used, the linearity of the blade edge will be poor due to reasons such as adhesion errors.

Cleaning is performed because the untransferred residual toner on the photoconductor passes through the area with poor linearity (i.e., the gap between the grade edge and the photoconductor surface) due to trenching and the grade edge not coming into uniform contact with the photoconductor surface. This will cause defects.

In addition, in the former structure, the elastic blade is fixed to the holding member with a screw, so in order to convert the elastic blade, the screw must be tightened and loosened, which requires a lot of work. It's a hassle.

In addition, when replacing the grade with the latter structure,
must be replaced together with the holding member, resulting in very high costs.

The present invention was made in view of the above circumstances, and its purpose is to provide a cleaning grade that can be replaced simply and at low cost, and that can also improve the linearity of the grade edge and provide optimal cleaning performance. To provide a cleaning grade holding device for a blade cleaning device ft, which allows the cleaning grade to be maintained.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is an overall front view, in which a cleaning grade holding member 2 (hereinafter referred to as grade holding member 2) is provided facing the surface 1α of p1 photoreceptor 1.
A grade mounting groove 4 into which a cleaning grade 3 (hereinafter referred to as grade 3) is inserted is attached to the photoconductor surface 1.
The blade edge 3α contacts the photoreceptor surface 1α with an appropriate pressing force and the blade edge 3α is formed toward α.
The untransferred residual toner on the photoreceptor 1 is scraped off and cleaned. The blade edge 3α becomes the cleaning edge.

The grade mounting grooves 4 are arranged in a first upper wall 5 that is substantially parallel to each other.
1 and a first lower wall 61, a second upper wall 52 and a second lower wall 62, which are substantially parallel to each other, and a vertical wall 7 for positioning, the rainbow photoreceptor surface 1α side is bent into a substantially V-shape with an opening 8. In addition, the distance between the upper wall 5 and the lower wall 6 (height of the blade mounting groove 4)
The thickness of the blade 3 is slightly larger.

In other words, the grade mounting groove 4 has a substantially doglegged shape with the upper and lower walls 5, 6 bent in a doglegged shape, and the vertical wall 7 with an interval slightly wider than the thickness of the rainbow blade 3. The angle α1 bordering on the bent portion 5' of the second upper wall 555z and the first. Second
The angle α1 between the lower walls 6+ and 62 at the bent portion 6' is equal to approximately I5 degrees.

On the other hand, as shown in FIG. 2, the blade 3 has an upper surface 3h, a lower surface 3c, both end surfaces 3d and 3g, and both side surfaces 3f.

3f, it becomes a thin plate-like body with a predetermined thickness t, a predetermined length, and a width approximately equal to the axial length of the photoreceptor 1, and both end surfaces 3d
, 3g are perpendicular to and parallel to the upper and lower surfaces 3A and 3c, and are made of elastic rubber such as polyurethane.

Then, the blade 3 is inserted into the blade mounting groove 4,
One end surface 3d is in contact with the vertical wall 7, and the grade 3 is positioned in the width direction, and the other end surface 3e is parallel to the axial direction of the photoreceptor surface 1α, and the linearity of the blade edge 3α is good, and the grade edge 3α is In addition to uniformly contacting the photoreceptor surface 1α in the axial direction, when the photoreceptor 1 is stopped, the blade 3'e can be easily removed and inserted from inside the blade mounting groove 4, and the grade holding member 2f can be removed from the device body to hold the grade. Since only the blade 3 can be easily replaced, the blade replacement work is simplified, and since the blade holding member 2 can also be used, the cost is reduced.

Further, when the photoreceptor 1 is moved in the direction of the arrow and enters the cleaning state, a pressure contact force of a predetermined appropriate value is applied to the means (not shown), so that the photoreceptor I is bent backward in the direction of movement and the blade 3 and The angle α2 formed between the tangential plane of the photoreceptor 1 at the contact line X and the blade 3 is an acute angle. In other words,
One wiper type.

At this time, the grade 3 is bent into a substantially doglegged shape within the grade attachment groove 4. In other words, the upper surface 3b contacts the vertical wall portion (a) of the first upper wall 51 and the opening portion (b) of the second upper wall 52, and the lower surface 3c contacts the bent portion 6' of the lower wall 6. Grade 3 is bent into a dogleg shape within the blade mounting groove 4, and its elastic restoring force frictionally engages the three points, so the photoreceptor 1
This movement prevents the grade from being removed from the inside of the grade mounting groove 4.

Figure 3 shows a state in which the blade 3 is free without being pressed against the photoreceptor 1 by simply inserting and mounting the grade 3 into the blade attachment #14 of the grade holding member 2, and t is held in the grade holding member 2. t' is the length of the free length of the blade, which is usually called the blade free length.
6, the length of the grade bent part formed on the Eri blade 3 at 6F, that is, the distance from the bent part 6' to the other end surface 3e).

Note that the thickness t is usually 2 to 5 m.

Considering the correlation between the total length and free length length t in the grade maintained as shown in Figure 3, if the free length t (that is, ■) is within a certain range with respect to the total length Appropriate leaning motion can be obtained.

In other words, if A is extremely small, the rigidity of the free length will be extremely high and it will come into contact with the photoreceptor surface in a state close to that of a rigid body, so the blade edge will be inserted into the blade holding member in a corrugated peg position. In this state, the grade bends and deforms, absorbs the corrugated nails, and does not take full advantage of its properties as an elastic material, which allows the grade edges to come into uniform contact with the photoreceptor, resulting in untransferred residual toner on the photoreceptor from the corrugated nails. This will cause cleaning failure.

In addition, when I is large (when the free length length t is long), the quality of the part held by the grade holding member becomes short, but the free length is large in the vicinity, so the characteristics of rubber as an elastic material are affected. becomes dominant.

In other words, the grade is receiving a certain appropriate pressure force, but since the free length length t is large, the grade absorbs the pressure force and bends, and the contact angle with the photoreceptor surface becomes smaller than the specified value F. , it becomes impossible to obtain the pressing force necessary for cleaning the surface of the photoreceptor.

As mentioned above, in order to obtain an appropriate cleaning action using a blade made of elastic rubber material, the free length length t is
It is necessary to set (L-) within an appropriate range to provide appropriate rigidity.

Therefore, various experiments were conducted to determine the value of T, and the following results were obtained.

Central test method Free length length t is 6 tux, 9 tux,
The cleaning efficiency was measured by changing the load t (pressing force) applied to the blade.

Results: The results shown in the front page of Figure 4 were obtained.

From the above, for example, considering the case where the applied load is +5 opf, the cleaning efficiency η is da6 and 1-9 wx in the case of t-61u1 (TJ-7).

This is significantly lower than in the case of 1-12m5, and to obtain complete cleaning (cleaning efficiency too%)
) required an applied load of approximately rsoo 9F.

Also, in the case of t -98('-Y), the cleaning efficiency η is η? In the case of Z-12ttux (TJ""7), the cleaning efficiency η slightly decreased to η12, and
In both cases, the applied load should be approximately 1,500,577 to obtain a complete leaning.

Further, the length n held by the blade holding member needs to be at least about 6u, and L-12wJ1 or less, that is, 4≦3, is not realistic.

L Ink' Also, the overall length of the grade cannot be made too long for reasons such as space, and is approximately 1 gm5.

From the above, in order to obtain the optimum cleaning performance using a grade of elastic material, r+22 should be approximately in the range of 7≦t≦7.

The present invention is as described above, and elastic cleaning grade 3
The elastic cleaning blade 3 can be easily removed from the blade holding member 2 by being bent into the blade mounting groove 4 of the blade holding member 2, and the elastic cleaning blade 3 can be easily replaced. Since the holding member 2 does not need to be replaced, the cost is reduced.

In addition, the positioning surface of the grade attachment groove 4 allows the elastic cleaning blade 3 to have good linearity and to uniformly contact the surface of the photoreceptor.

1.11-2 Optimum cleaning performance can be obtained by setting the range of 7≦≦7.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, and FIG. 1 is an overall front view;
FIG. 2 is a perspective view of the grade, FIG. 3 is a front view of the blade in a state where it is held, and FIG. 4 is a front view showing the relationship between the load applied to the grade, cleaning efficiency, and free length length. f is the photoreceptor, 1α is the surface, 2 is the plate holding member, 3
is an elastic cleaning grade, and 4 is a grade mounting groove. Applicant: Fuji Xerox Co., Ltd. Agent: Patent Attorney: Masaaki Yonehara Patent Attorney: Tadashi Hamamoto

Claims (1)

[Scope of Claims] In a grade cleaning device that scrapes off and removes untransferred residual toner on the photoreceptor by bringing the elastic cleaning grade 3 into full pressure contact with the surface 1α of the photoreceptor, the elastic cleaning blade 3 is attached to the holding member 2 of the elastic cleaning blade 3. A grade mounting groove 4 is formed which has a positioning surface and a receiving opening for supporting the blade 3 in the entire 1α line shape on the mounting end surface of the blade 3, and has a bent part in the middle between the positioning surface and the receiving opening, and the blade is mounted. One end of the elastic cleaning blade 3 is bent and inserted and held in the groove 4, and the free length portion is positioned forward in the direction of photoreceptor movement with respect to the one end holding portion, and the entire length of the elastic cleaning blade 3 is The relationship between the length and the length of the free length part is 1 t
2.Ps characterized by being within the range of 1≦−≦−
Cleaning blade holding device for L s Rade Cleaning IT.