JPS5915970A - Forming method of blade - Google Patents

Abstract

PURPOSE:To form a cleaning blade whose plane accuracy is good, by providing unevenness on a casting face in a centrifugal casting method, injecting a liquid rubber substance onto its uneven face, and executing the centrifugal formation, when forming a blade having an uneven face. CONSTITUTION:First of all, a centrifugal cylinder 3 is rotated under heating, and when the rotation reaches a stable state, liquid rubber is injected. When the rotation is continued, a rubber liquid layer having unevenness against that of the surface, as shown by a two point chain line 13 is formed on the surface of the centrifugal cylinder 3. During this time, defoaming of the liquid layer is also attained. Subsequently, a rubber solidified layer 4 obtained by solidifying said liquid layer is formed in the inside of the centrifugal cylinder 3. Subsequently, the rotation of the centrifugal cylinder 3 is stopped, the solidified rubber layer 4 is stripped off from the inside of the cylinder 3, the rubber layer is matured, and thereafter, is cut in conformity with a standard of the blade, and the finish work is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention II relates to a method for forming a blade installed in a blade cleaning device such as an electrophotographic copying device.

As is well known, the blade cleaning device according to the present invention has a substantially rectangular elastic blade B held by a holding frame H on the surface of the photosensitive drum D, which is the surface to be cleaned, as shown in FIG. This is a device that performs cleaning by pressing the photosensitive drum D against it and rotating the photosensitive drum D in this state to remove the developer on the surface to be cleaned. The blade attachment mechanism of such a conventional blade cleaning device is known as shown in FIGS. 2, 3, and 3'. As shown in Fig. 2 and Fig. 3', the holding frame 1 consists of a fixed frame 1a and a clamping frame 1b, and the elastic blade 2 is fixed with screws. In addition to the need for fixing, it is difficult and difficult to fix the blade with a uniform force in the longitudinal direction, and it is desirable to attach it with precision.Furthermore, when the temperature inside the machine changes, time-keeping frame 1 and bullet 1 There is a drawback that the elastic blade 2 may curve due to the difference in thermal expansion coefficient with the cow blade 2. Further, as shown in FIG. 3, the holding frame 1 is formed by curving the fitting surface into which the elastic blade 2 is immediately inserted, and the elastic blade 2
When inserted, it bends according to the curvature of the fitting surface, and the elastic blade 2 is fixed by its elastic restoring force.In this case, the elastic blade 2 can be easily installed, and the elastic blade 2 can be easily installed in a direction perpendicular to the bending for installation. Although this has the advantage that curving is less likely to occur, it has the disadvantage that mounting accuracy is difficult to obtain due to the bending, and it is difficult to form a parallel curved fitting surface of the holding frame 1.

In order to eliminate the drawbacks of the mechanism described above, the blade installation is fixed simply by inserting it, and the high-speed installation allows for precision and prevents bending even when the temperature inside the machine changes. Junto Honde previously proposed a blade that uses a mechanism to attach the blade, which eliminates the need to form a holding frame and makes it relatively easy to form a holding frame (Utility Application No. 1987-66626).
. That is, as shown in FIG. 4, the elastic blade 2 has a holding frame 1.
A groove 21 is provided which engages with the projection 11 of. In addition, in the row of FIG. 5, a groove 11a is provided in the holding frame l instead of a projection, and this /#J1a [a projection 21a provided on the elastic blade 2 engages with the groove 11a.

In this way of bonding! il note blade 2
The elastic blade 2 can be inserted relatively easily while engaging the groove 21 or the protrusion 21 a of the holding frame 1 with the protrusion 1 or the groove II a of the holding frame 1.
will be installed. That is, the elastic blade 2 inserted in the above-mentioned state is reliably maintained in that state by compression by the protrusion 11 or engagement between the protrusion 11 and the groove 21 or the groove 11a and the protrusion 21a.

In the case of blade cleaning, the blade tip and the surface to be cleaned, as shown in Fig. 1, are rectangular in shape, and the main phase movement is carried out in the direction perpendicular to the longitudinal direction of the blade. In this case, a force is applied to pull the blade away from or push it into the holding frame. As mentioned above, by the engagement between the protrusion of the holding frame and the blade, or the engagement between the groove of the holding frame and the protrusion of the blade, the holding frame can reliably hold the blade against the above-mentioned pulling apart or pushing force. This reliably prevents the blade from slipping from the holding frame during the cleaning operation.

Centrifugal casting, injection molding, and press molding are known methods for molding the blades to be mounted on the blade cleaning device described above.

The pressing method is not suitable for forming useful blades as described above, in which unevenness etc. are provided on the blade surface.
injection molding method has been used.

However, in the injection molding method, it is difficult to remove air bubbles during the injection assimilation process of blade stripping, and the air bubbles form on the blade surface that contacts the drum, causing problems in cleaning, and the flatness accuracy is poor. It is extremely difficult to use as a cleaning blade that requires flatness accuracy and installation accuracy.

Based on the above circumstances, an object of the present invention is to provide a method for molding a cleaning blade with good planar accuracy.

Further, the purpose of @2 is to provide a cleaning blade with good mounting accuracy.

The object of the present invention is to provide a method for forming a blade having an uneven surface, characterized in that a casting surface in a centrifugal casting method is provided with unevenness, and a liquid rubber substance is press-fitted onto the uneven surface for centrifugal molding. Achieved by molding method.

The unevenness imparted to the blade during this molding is done in the longitudinal direction of the blade, in accordance with the blade engagement type of the blade holding frame.
Any form such as ridges or grooves in the width direction, or arrayed depressions, protrusions, or holes can be adopted.

Next, the present invention will be explained using one of the embodiments.

FIG. 7 illustrates a centrifugal casting method in which grooves or depressions are provided on the blade.

In the figure, 3 is a centrifugal cylinder, and 31 is a projection for providing grooves or depressions on the blade.

It is not necessary to say that the arrangement of the protrusions and the weight distribution are sufficiently balanced with respect to the rotation of the centrifugal cylinder 3.

0 is the center axis of rotation of the centrifugal cylinder 3.

First, the core cylinder 3 is rotated while being heated, and when the rotation reaches a stable state, liquid rubber (molten rubber or a rubber solution dissolved with an organic yeast) containing a crosslinking agent is injected if necessary. By continuing the rotation, a rubber liquid layer is formed on the surface of the centrifugal cylinder 3, as shown by the two-dot chain line 13, which has irregularities similar to the irregularities on the surface. During this time, defoaming of the liquid layer is also done exclusively.

Next, these seven layers are solidified by the progress of crosslinking or evaporation of the solvent, and a solidified rubber layer 4 as shown in FIG. 6 is formed inside the centrifugal cylinder 3.

Next, the rotation of the centrifugal cylinder 3 is stopped, the solidified rubber layer 4 is peeled off from the inner surface of the centrifugal cylinder 3 using rubber elasticity, and after the rubber layer is aged, it is adjusted to the specifications of the blade to be installed in the blade cleaning device. The material is then cut and finished.

When adding ridges, protrusions, or holes to the blade,
A blade can be similarly formed by providing a groove, a depression, or a protrusion on the inner surface of the centrifugal cylinder 3.

The arrangement direction of the grooves, ridges, depressions, and protrusions provided on the inner surface of the centrifugal cylinder 3 is arbitrary as long as it does not disturb the rotational direction of the centrifugal cylinder 3, and can be freely changed depending on the blade engagement type of the gripper frame. .

In addition, the particles used for the blade include 1) urethane rubber, 2)
) silicone rubber, 3) styrene-butadiene rubber (sB
R), 4) Butadiene-acrylonitrile rubber (NB
R), 5) chlorprene rubber, or 6) fluororubber, or other rubber materials are used, and urethane rubber is particularly preferred.

When the shredded rubber material is fermented in a solvent and cast, M-shavings include benzene, l-threnine, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, methyl ethyl ketone, chloroform, or tricrene. etc. can be used.

The blade obtained in this manner is convenient for engagement with the holding frame, is completely defoamed, has no bubbles missing, and has extremely good flatness. Furthermore, the thickness accuracy is sufficiently uniform, which makes the blade extremely desirable in mounting and cleaning effects.

Next, a more specific explanation will be given by listing the implementation rows.

FIG. 7 shows a sectional view of one row of the centrifugal casting apparatus 5 used in the present invention.

As shown in the figure, the bottom of the heating jacket 6 is inserted into a box-shaped heating jacket 6 whose outer periphery is covered with a heat insulating jacket 7 and has a heating fluid passage 8 inside, and whose opening is closed with a canopy 9. Then, one end of the rotation center shaft 0 provided to rotate the motor 10f was inserted, and using a centrifugal casting device 5 in which one end of the centrifugal cylinder 12 was fixed to one end of the rotation center shaft 0, the following procedure was carried out. A blade having concavities and convexities for locking was manufactured.

The centrifugal cylinder 12 has a plurality of cylinders with a height of approximately 2 in the circumferential direction.
A ridge of mm was provided.

A centrifugal cylinder 12 with an inner diameter of 210 mm and a length of 250 mm is 1
A blade plate was manufactured by the following method while rotating at 00°r, p, m. That is, desmorphen (D
esmophen) 2+200 (Polyester manufactured by Bayer) 100
15 parts of Desmodur) 15 (incyanate compound manufactured by Bayer) and 125 to 13 parts of
The reaction was carried out for several tens of minutes in a molten state at 0°C to obtain a primary reaction product consisting of leg-like polyurethane, and 1 to 2 parts of a crosslinking agent was immediately added thereto and stirred for about 10 minutes to produce a secondary reaction product containing a crosslinked structure. The product was obtained and poured into the casting surface (inner surface) of a rotating centrifugal cylinder 12 preheated to about 120° C. while fluidity was being determined. In this way, a rubber liquid layer indicated by a two-dot chain line 13 is formed, and the crosslinking reaction progresses in this rubber liquid layer for several minutes to
It solidified in several ten minutes. The obtained solidified rubber layer 4 was peeled off and taken out, heat treated in a heating furnace at about 120° C. for one night, and aged at room temperature for about 6 to 8 days to obtain a target product having an inner diameter of 204 mm as shown in FIG. 6. . After examining the thickness distribution of the target object,
The error had an accuracy of 110 μm.

This was then cut and finished according to the R blade specifications.

[Brief explanation of the drawing]

Figure A1 is a schematic perspective view of the blade cleaning device, Figures 2, 3 and 3' are explanatory diagrams of the conventional blade holding type, and Figures 4 and 5 are illustrations of the blade cleaning device according to the present invention. FIG. 6 is a sectional view of a solidified rubber layer, and FIG. 7 is a sectional view of a centrifugal casting apparatus according to the present invention. DESCRIPTION OF SYMBOLS 1... Holding frame, 2... Blade, 4... Assimilated rubber layer, 11... Holding frame protrusion, 21... Blade handle, 3 and J2... Centrifugal cylinder, 31... Protrusion on the inner surface of the centrifugal circle, 0...Rotation center axis, 5...Centrifugal casting device, 6.
... Heating jacket, 1 32... Depression in the solidified rubber layer, Agent Yoshi Nahara, Mimi 4 Figure 11 and 1 5 Figure 4 Procedural amendment (Ohe) Patent chief' Kazuo Showa Wakasugi 1982 Patent Application No. 126062 - Name of the invention Relationship to the case involving a person who uses a blade forming method
Name (+271 Konishiroku Photo C Co., Ltd. Jshi Director Nobuhiko Kawamoto Agent Address: 191 Tokyo IEI Wf il + Sakuri-cho 1 Cloth II+ Column of “Detailed description of the invention” in the specification (+++
) "Brief explanation of drawings" column 7 of the specification. Contents of correction (1) Figure 3' is corrected as shown in the attached sheet. (1. Correct “Figure 3′” in the first and second lines of page 2 of the amended specification box in the “Detailed Description of the Invention” column to “Figure 8.” (m) r Drawing The "Brief Description" column has been corrected as follows: "Figure 1 is a perspective view for explaining the cleaning device, and Figures 2, 3, and 8 are side views showing the conventional blade holding type. Figures 4 and 5 are side views showing the blade holding type according to the present invention, Figure 6 is a side view showing the expanded state of the rubber solidified layer made by centrifugal casting, and Figure 7 is the main 1 is a schematic diagram of a centrifugal casting apparatus including a cross section of a

Claims (1)

[Claims] In the method of forming a blade with an uneven surface, the casting surface in the centrifugal casting method is provided with unevenness, and a liquid rubber substance is injected onto the uneven surface to form a water core! Blade forming method for ¥jm.