JPS6230283A - Manufacture of cleaning blade for electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To substantially improve a defect ratio in terms of an overall end surface being the collating part of the tips of U-shaped sides as 1st and 2nd molds by holding the lower part of the adhesive coating surface of a platelike holding member not so as to incline said member from a mold closed and chained state to a mold injecting step. CONSTITUTION:A mold whose end surface is made smaller is used for the 1st and 2nd molds 11 and 12 so that the collating part of the both U-shaped sides does not hold the upper adhesive coating surface of the platelike holding member 3 but its lower part. With such the constitution the end surface being the collating part of the 1st and 2nd molds securely holds some part of the metallic platelike holding member on which an adhesive is coated, instead of the adhesive coating surface, whereby the inclination of the platelike holding member will not occur, different from a conventional method, and the occurrence of defects can be considerably prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a cleaning blade for an electrophotographic copying machine that removes toner remaining on a photosensitive drum for an electrophotographic copying machine.

[Conventional technology]

An electrophotographic copying machine is equipped with a photosensitive drum having a photoconductor surface layer, and the outer circumferential surface of the photosensitive drum is uniformly charged, and then the outer circumferential surface is exposed to light through an image to be copied of an object. Copying is performed by forming an electrostatic latent image on the outer circumferential surface, applying toner to the electrostatic latent image to form a toner image, and transferring this to copy paper or the like. Since toner remains on the outer circumferential surface of the photosensitive drum after the copying, it is necessary to remove this residual charged toner, and this removal is performed using a cleaning blade. This cleaning blade is shown in FIG. In the figure,
1 is a cleaning blade for an electrophotographic copying machine (hereinafter abbreviated as "cleaning blade"), in which a thick plate-shaped soft urethane resin blade member 4 is attached to the upper end of a metal plate-shaped holding member 3 with a flange 2; It is configured by attaching it in the same direction. In this case, the tip of the plate-shaped holding material 3 is covered with the adhesive layer 6, and the blade member 4 is covered with the adhesive layer 6.
The blade member 4 enters into the rear end portion, thereby integrating the blade member 4 and the plate-shaped holding member 3. As shown in FIG. 6, the cleaning blade 1 brings its blade member 4 into pressure contact with the photosensitive drum 5 rotating in the direction of the arrow to scrape off residual toner (not shown). In this case, the mounting position of the cleaning blade l is set in advance,
Since the pressing angle and pressing force of the blade member 4 with respect to the photosensitive drum 5 are also set in advance, the cleaning blade 1 is required to be precisely finished in terms of shape and dimensions.

As mentioned above, cleaning blades that require precision finishing are manufactured in the following manner. That is,
As shown in FIG. 7, adhesive is applied to the upper end edge of the plate-shaped holding member 3 with flanges 2 by dipping, the upper end edge is covered with an adhesive layer 6, and two of the adhesive layers are applied to the upper end edge. With the edge facing inward, the mold is placed between the first and second molds 7 and 8, each having a substantially U-shaped cross section, and the two sides of the U-shape are brought together. After closing, the mold in the closed state is erected and urethane resin liquid is poured into the mold from the opening 9 therebetween. After the urethane resin is cured to form a blade member, it is removed from the mold to produce a molded body with plate-shaped holding members 3 protruding from both sides of a wide blade member 4, as shown in FIG.

Next, the wide blade member 4 of this molded body is cut along the chain lines shown in the figure to produce two cleaning blades 1.

[Problem that the invention seeks to solve]

However, when manufacturing the cleaning blade l as described above, the blade member 4 is inclined with respect to the plate-shaped holding member 3 of the cleaning blade 1, as shown in FIG. is manufactured at a considerable rate. In an electrophotographic copying machine, the mounting position of the cleaning blade 1 is set in advance, and a machine in which the blade member 4 is slanted as described above does not conform to this and is inevitably a defective product.

The purpose of this invention is to reduce the incidence of defects.

[Means for solving problems]

In order to achieve the above object, the manufacturing method of the present invention prepares a plate-shaped holding material whose upper end edge is coated with an adhesive by dipping, and whose cross-sectional shape is approximately U-shaped. a step of preparing first and second molds having a shape of 100 mm, and a step of abutting the tips of both U-shaped sides of the first and second molds and applying the plate-shaped holding material to the abutting portions, and applying the plate-shaped retaining material to the upper end edge a step of closing the mold by sandwiching the parts inside, a step of pouring a resin liquid for the blade member from one opening in the mold in the closed state, and a molded product obtained by curing the resin liquid.
．． The step of removing the mold from the second mold is provided, and when the mold is in the closed state, the entire end face that is the abutting part of the tips of both sides of the U-shape of the first and second molds is shaped like the plate. The configuration is such that the lower part of the holding material is held, rather than the adhesive-coated surface of the upper end.

That is, the inventors investigated the causes of the above defects and found the following. That is, conventionally, in the mold closing process, a plate-shaped holding material is sandwiched between the abutting parts of both U-shaped sides of the first and second molds. Not only the non-adhesive-coated surface of the holding material but also the adhesive-coated surface is sandwiched. However, the adhesive-coated surface is more raised than other parts, and if this part is sandwiched, the other parts will not be sandwiched, and essentially only the adhesive-coated surface will be sandwiched. Moreover, since the adhesive layer on this adhesive-coated surface is softer than other parts, the plate-shaped holding material will tilt with a small force. Therefore, it will tilt due to the pressure during mold clamping, etc. In particular, this phenomenon is caused by the fact that the adhesive is applied by dipping to achieve mass production effects, and it is difficult to apply the adhesive uniformly. Therefore, the inventors discovered that when the mold is closed, the end surfaces of the first and second molds, which are the abutting parts, can be used to protect the surface of the plate-shaped holding material from its lower side, rather than the adhesive-coated surface. They believed that retaining the parts that were not coated with adhesive would eliminate the adverse effects of dipping and bring about good results, and as a result of experiments, they found that the number of defective products was significantly reduced, and they arrived at this invention.

Next, the present invention will be explained based on examples.

〔Example〕

FIG. 1 is a manufacturing explanatory diagram of an embodiment of the present invention. That is, in this embodiment, the first. As the second mold 11.12, the end faces of both sides of the U-shape are shaped so that the end faces serving as the abutting parts sandwich the lower part of the plate-shaped holding material 3 instead of the upper adhesive-coated surface. A smaller mold is used. The rest is the same as the conventional example shown in FIG.

As a result of this configuration, the first. The end face of the second mold, which is the mating part, firmly holds the part of the metal plate-shaped holding material that is not coated with adhesive, rather than the adhesive-coated surface, so it is not plate-shaped as before. The holding material does not tilt, and the occurrence of defects can be largely prevented. Moreover, as a result of the above configuration, the first. Second type 11.1
2 is closed, the mold is erected, and the resin liquid is poured into the mold. As shown in FIG. It comes to fit within the cavity 15. Therefore, when casting resin liquid,
The resin liquid flows smoothly through the gap 15 where the adhesive N6 is not present, preventing any air bubbles from remaining, and the additional effect of preventing air shortages due to residual air bubbles from occurring. It becomes like this. This will be explained with reference to FIGS. 3 and 4. FIG. 3 is an explanatory diagram illustrating the casting state of the resin liquid 13 (the first mold is removed for convenience of illustration), and FIG. 4 is an enlarged view of the circled part 2. In FIG. 4, a indicates a portion of the gap 15 where the adhesive layer 6 (indicated by diagonal lines) does not exist, and a curve C indicates the flow state of the resin liquid 13 flowing down through a wide section of the flow path in the mold. , and the curved line indicates the flow state of the resin liquid 13 when the resin liquid 13 that has flowed down through the wide part of the cross section of the flow path hits the bottom of the mold and reverses and rises. Curves E and F indicate the resin liquid 1 when it reverses and rises inside the gap 15.
3 flow state is shown. In these curves C-F, the flow rate of the resin liquid 13 is shown to be slower in the higher part of the curve C-F. That is, in this example,
The first one has a small end surface that becomes the abutting part. Second type 11.
12, sandwich the adhesive layer 6 between the end abutting parts of both molds 11 and 12, and then cover the end abutting part with the adhesive layer 6.
Since the mold is not airtightly sealed, when the mold is closed and the resin liquid 13 is poured into the mold, the resin liquid 13 that hits the bottom of the mold and reverses and rises will not flow into the area where the ends of the two molds meet. While discharging air from between the abutting surfaces (resin liquid does not leak because of its high viscosity), it rises smoothly through the gap 15. Therefore, no air bubbles remain and no air shortage occurs. Further, as shown in FIG. 2, the adhesive layer 6 at the upper end of the plate-shaped holding member 3 is surrounded by resin liquid, so that the adhesive layer 6 is directly surrounded by the tube 1. Second type 11.12
Since the mold surface is not in contact with the mold surface, it is possible to prevent the mold release agent applied to the mold surface from penetrating into the adhesive layer 6 and causing adhesive failure. That is, in the conventional example, as shown in FIG. 8, since the adhesive layer 6 is in direct contact with the mold surface,
However, this example product had the disadvantage that the release agent applied to the mold surface penetrated into the adhesive layer 6 and weakened the adhesive force, causing adhesive failure during use of the cleaning blade. Well, that's not the case.

〔Effect of the invention〕

As described above, according to the present invention, in the mold closed state, the first . The entire end surface of the second mold, where the tips of both sides of the U-shape meet, grips the lower part of the plate-shaped holding material instead of the adhesive-coated surface, so the mold is in a closed state. This prevents the plate-shaped holding material from tilting during the casting process, making it possible to significantly reduce the defective rate. Furthermore, it is possible to obtain the additional effect of preventing defects due to air deficiency and adhesive failure of the blade member during use.

[Brief explanation of the drawing]

Fig. 1 is a manufacturing explanatory diagram of an embodiment of this invention, Fig. 2 is a plan view of the mold in the closed state, Fig. 3 is an explanatory diagram of resin liquid casting, and Fig. 4 is an enlarged view of the circled part. Figure 5 is a perspective view of a conventional cleaning blade, Figure 6 is an explanatory diagram of its use,
FIG. 7 is an explanatory diagram of the one shown in FIG. 5, FIG. 8 is a front view of the molded product obtained in FIG. 7, and FIG. 9 is an explanatory diagram of an example of a defective cleaning blade. 3--Plate holding material 4-Blade member 6-Adhesive layer 11--First mold 12--Second mold 15-Gap patent applicant Tokai Rubber Industries Co., Ltd. $2 Figure 4 Figure 4 Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] (1) Prepare a plate-shaped holding material whose upper end edge is coated with adhesive by dipping along the edge, and prepare first and second molds whose cross section is approximately U-shaped. a mold closing step of abutting the tips of both U-shaped sides of the first and second molds and sandwiching the plate-shaped holding material between the abutting portions with the upper end edges inside; , a step of casting a resin liquid for a blade member from one opening in the mold in a closed state, and a step of demolding the molded product obtained by curing the resin liquid from the first and second molds, In the mold closed state, the entire end surface where the tips of both sides of the U-shape of the first and second molds meet is not the upper adhesive-coated surface of the plate-shaped holder, but the lower part thereof. 1. A method for manufacturing a cleaning blade for an electrophotographic copying machine, characterized in that the cleaning blade is sandwiched between the blades.