JPS6156380A - Manufacture of cleaning blade for copying machine - Google Patents

Abstract

PURPOSE:To shorten a manufacturing process, and to reduce a working cost by using a thermoplastic elastomer whose low elongating stress, compression set and Ryupuke impact resilience coefficient are prescribed values, respectively, and manufacturing a cleaning blade by an injection molding machine. CONSTITUTION:A pellet-shaped thermoplastic resin 2 (prescribed thermoplastic elastomer) is thrown into the hopper 1 of an injection molding machine 100. Subsequently, the resin 2 is extruded to a heating part 4 by a plunger 3 and formed to a molten state resin 5. Next, the resin 5 is extruded to the cavity 11 of a prescribed shaped divided by cavity plates 8, 9 and a cavity piece, from plural runners and gates, by which a cleaning blade is manufactured. Accordingly, comparing with a centrifugal molding machine, the manufacturing process of the cleaning blade is shortened, and the working cost can be reduced.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for manufacturing a cleaning blade for a copying machine, and more specifically, the invention relates to a method for manufacturing a cleaning blade for a copying machine, and more specifically, a method for manufacturing a cleaning blade for a copying machine using a thermoplastic elastomer as a material by an injection molding machine or an extrusion molding machine. It relates to a manufacturing method.

[Prior art]

In general, in electronic copying machines, especially in so-called PPC copying machines that use plain paper as recording paper, cleaning the photoreceptor (drum) has an important effect on copying performance, so the cleaning blade should be cleaned with a high-precision product. There is a need. This cleaning blade cleans and removes the toner remaining on the photoconductor by directly contacting the surface of the moving photoconductor (drum) with its edge (ridge line). Accuracy is a critical issue.

Generally, the accuracy of this edge portion is preferably 10 μm or less, and if it is 10 μm or more, a ghost image or stringiness will appear on the recording paper, resulting in poor copying.

By the way, conventional cleaning blades for copying machines are molded from thermosetting polyurethane resin for reasons such as durability and molding accuracy.The manufacturing method for this blade is to mold thermosetting liquid elastomer into a centrifugal molding machine. A second vulcanized sheet is produced, and this first vulcanized sheet is placed in an oven for two
After the next vulcanization, the product is finished by cutting into a predetermined blade size after an aging process.

However, in the case of such conventional manufacturing methods, it is difficult to manufacture highly accurate products due to large variations in quality due to the large number of manufacturing steps. It takes a lot of time and effort to
There was a problem in that the processing cost increased.

Furthermore, when a primary vulcanized sheet of a certain length is manufactured using a conventional centrifugal molding machine, wrinkles and bubbles may occur on the surface of the sheet material due to the thermosetting liquid, making it difficult to manufacture cleaning blades of constant quality. Furthermore, when cleaning blades are cut from a sheet material of a certain length, the generation rate of so-called scraps increases, making it impossible to efficiently manufacture cleaning blades.

[Purpose of the invention]

1.1 This invention was devised by focusing on the conventional problems, and its purpose is to shorten the manufacturing process, reduce processing costs, and stabilize quality. The present invention provides a method for manufacturing a cleaning blade for a copying machine, in which a highly accurate cleaning blade can be manufactured, and furthermore, the cleaning blade can be manufactured efficiently by reducing the waste rate from the sheet material.

[Structure of the invention]

In order to achieve the above object, the present invention manufactures a cleaning blade using an injection molding machine or an extrusion molding machine using a thermoplastic elastomer having predetermined values of low tensile stress, compression set, and Lübcke rebound modulus. The gist of this is that

[Embodiments of the invention]

The present invention will be described in detail below based on the accompanying drawings.

1 to 5 show a first embodiment of a method for manufacturing a cleaning blade W according to the present invention using an injection molding machine 100.
[The method for manufacturing the cleaning blade W using this injection molding machine 100 is as shown in FIG. thermoplastic elastomer). Then, this thermoplastic resin 2 is extruded into a heating section 4 by a plunger 3 to form a molten resin 5, and this molten resin 5 is passed through a plurality of runners 6 as shown in FIGS. 2 and 3.
The leaning blade W is then extruded from the gate 7 into a cavity 11 of a predetermined shape defined by cavity plates 8, 9 and a cavity piece 10 to produce a leaning blade W as shown in FIG.゛Above, Runner 6
As shown in FIG. 3, the structure of the plurality of gates 7 is such that a plurality of runners 6 are formed at predetermined intervals in a nozzle 12 of the molten resin 5, and a small-diameter cavity 11 is formed at the tip of the runner 6. A gate 7 communicating therein is formed.

Furthermore, in order to prevent uneven extrusion pressure when extruding the molten resin 5 into the cavity 11, the runner 6 and gate 7 are formed in a slit shape and a tapered shape as shown in FIG. or the nozzle 12 and cavity 11
The opening area may be changed depending on the distance from the

In Fig. 1, 13 is a cooling water hole, 14 is a product release pin, and a, b, c + d of the cleaning blade W shown in Fig. 5 indicate four ridgelines, and the ridgelines used are It is a.

Further, the conditions for the method of manufacturing the cleaning blade W using the injection molding machine 100 are as follows.

(a), Injection pressure...450kg/cI11, (b)
, resin temperature...190℃, (C), cavity plate temperature...50℃, (d
), injection time: 6 seconds, (e), cooling time: 20 seconds, and the physical properties of the cleaning blade W made of thermoplastic elastomer material are as follows: shall be.

+1), 25% low elongation 15-100 kg/
cnl.

(2) Compression set: 40% or less; (3) Lübcke rebound modulus: 25% or more;

A cleaning blade W with a length of 200 pieces was manufactured.

As shown in Fig. 5, when the roughness of the used ridgeline part a (edge part) of the molded product of the leaning blade W was measured, the accuracy of the edge part was less than 110l1, which is similar to that of a cleaning blade for a photosensitive drum of a copying machine. The accuracy was such that it could be used as a W.

Note that the shape of the runner 6 for which highly accurate ridge lines are required is a slit shape as shown in FIG. 4, as described above.
It is also formed into a tapered shape.

Next, FIGS. 6 and 7 show a second embodiment of a method for manufacturing a cleaning blade W according to the present invention using an extrusion molding machine 200.

This extrusion molding ta200 is a known one, and 21 is a pump into which pelletized thermoplastic resin (for example, thermoplastic urethane elastomer I-mer, thermoplastic polyester elastomer, polyolefin-based thermoplastic elastomer, etc.) is introduced. Extruder equipped with 22, 23 is Gui, 24
25 is a finishing roll, 25 is a transport cooling unit, 26 is a take-up roll, 27 is a transport roller, 28 is an edging machine, 29 is a transport roller, 30 is a cutting machine, 31 is a product stacking device, etc. There is.

Next, using the extrusion molding machine configured as described above, cleaning plate 1! A first example of manufacturing W will be described.

First, thermoplastic polyurethane peresene 2102-75Ax (chemical upgrade) was dried at 90°C for 2 hours in advance.
2000u+ in length using the above extrusion molding machine,
A sheet material w1 having a width of 1000 m and a thickness of 3 mm is created.

The surface roughness of the sheet material is 5. or less.
(The conditions of the extrusion molding machine 200 were set as follows.

(a), Screw L/D failure 24, (b), Cylinder temperature...190℃, (C), Gui temperature...190℃, (d), Resin temperature...210℃, like this Under the conditions, the sheet material Wl was cut into predetermined dimensions by extrusion molding [200] to form the leaning blade W as shown in FIG. , all 5.
crm or less, it was found that it could be used as a cleaning surface for photoreceptors (drums).

Next, a second embodiment in which a cleaning blade W is manufactured using an extrusion molding machine 200 similar to that described above will be described.

First, using thermoplastic polyester Hytrel HT C23514056 (Toyo Products (!Kiku)), which had been previously dried at 107°C for 4 hours, a sheet material having a length of 200Q++m, a width of 1000mm, and a thickness of 2fl was created using the extrusion molding machine at 2°O. .

The surface roughness of the sheet material W1 is 53 or less.

The conditions for extrusion molding ta200 were set as follows.

(a), Screw L/D-24, Cylinder temperature...180℃, (C), Gui temperature...190℃, (d), Resin temperature...205℃, These conditions As a result of cutting the sheet material obtained in 1 to predetermined dimensions and forming a cleaning blade W, the ridgeline portions 1a, lb, 1c+ld of the cleaning blade W are all 5 μm or less, and can be used as a cleaning surface for the photoreceptor (drum). It was found to be usable.

As described above, it has been found that no matter which machine is used to mold the cleaning blade W, an injection molding machine or an extrusion molding machine, the precision of the ridgeline part used is such that it can be used as a cleaning surface for the photoreceptor (drum). Ta.

〔Effect of the invention〕

As described above, the present invention provides low elongation stress, compression set,
Since the cleaning blade is manufactured using an injection molding machine or an extrusion molding machine using a thermoplastic elastomer having a predetermined value of Lübcke rebound modulus and Lübcke rebound modulus, it is difficult to manufacture the cleaning blade using a conventional centrifugal molding machine. In comparison, the manufacturing process can be shortened,
As a result, processing costs can be reduced, quality can be stabilized, and a cleaning blade with even higher precision can be manufactured. Further, since the waste rate is reduced from the sheet material, the cleaning blade can be manufactured efficiently, and it is also possible to integrally mold the cleaning blade with a reinforcing support member such as a metal fitting.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of an injection molding machine according to the present invention, in which FIG. 1 is a sectional view of the injection molding machine, FIG. 2 is an enlarged sectional view of the cavity, and FIG. 3 is a sectional view of the injection molding machine. is m in Figure 2
-m arrow sectional view, Figure 4 is a sectional view showing another embodiment of the sunner, Figure 5 is a perspective view of a cleaning blade manufactured by an injection molding machine, and Figure 6 is a schematic configuration of an extrusion molding machine. 7 are perspective views of a cleaning blade manufactured by an extrusion molding machine. 100... Injection molding machine, 200... Extrusion molding machine, W
...Cleaning blade.

Claims (1)

[Claims] A cleaning blade for a copying machine, characterized in that the cleaning blade is manufactured by an injection molding machine or an extrusion molding machine using a thermoplastic elastomer having predetermined values of low tensile stress, compression set, and Lübcke rebound coefficient. manufacturing method.