JPH0471835A - Manufacture of rubber roller containing short fiber - Google Patents

Abstract

PURPOSE:To easily manufacture a roller containing short fibers orientated in a radial direction by inserting an elongated rod of a round section into the center of the forming cavity of a form with an annular dam provided on its forming surface, supplying short fiber-containing elastomer into the forming cavity, feeding the elastomer and the elongated rod toward an extrusion direction and performing vulcanization and cure. CONSTITUTION:On the forming surface of a forming cavity 1a is provided a projected annular dam part 6 having an inner diameter smaller than that of the forming cavity 1a and a predetermined length in its axial direction. An elongated rod 7 is inserted into the central part of the forming cavity 1a of a form 1 and is continuously fed toward an extension direction together with short fiber-containing elastomer formed around the elongated rod 7. Simultaneously, the unvulcanized short fiber-containing elastomer 5 is supplied into the cavity between the form 1 and the elongated rod 7 from a screw part 4. The short fiber-containing elastomer 5 and the elongated rod 7, both being extruded, pass continuously through a heating oven adjacent to the form 1, whereby vulcanization and cure are performed in succession with forming.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a rubber roller containing short fibers in which short fibers are oriented in the radial direction.

(Prior art) Conventionally, when manufacturing a short fiber-containing roller in which short fibers are oriented in the radial direction, a sheet in which short fibers are oriented in the thickness direction is first produced, and this is used as a core bar. It is customary to manufacture a rubber roll by wrapping it around a shaft member to form a rubber roll and then vulcanizing it.

However, in such a manufacturing method, a sheet is first manufactured, and then this is wrapped around a shaft member that becomes a core metal and molded.
Manufacturing is troublesome. Therefore, for example,
As described in Japanese Patent Application No. 231, it is known that a hose in which short fibers are oriented radially is manufactured, so this hose is cut into a predetermined size in the axial direction,
It is also conceivable to manufacture a rubber roller containing short fibers by using it as a rubber roll part and inserting a core bar into the center hole.

(Problem to be Solved by the Invention) However, in the hose described above, the shape of the center hole (inner diameter) is not regulated after extrusion molding, so the accuracy of the inner diameter of the center hole is not stable, and the rubber roll When inserting the core metal into the rubber roll part, the fit between the rubber roll part and the core metal becomes unstable, making stable production impossible.

Further, as described in, for example, Japanese Patent Application Laid-Open No. 62-285812, a process of covering the peripheral wall of the core metal with a rubber fabric,
A method has been proposed that includes the steps of inserting a core metal coated with the rubber fabric into a cylindrical mold, and heat-treating the outer shape of the core metal coated with the rubber fabric inserted. However, with this method, the short fibers can only be oriented in the radial direction, and the ends of the short fibers cannot be exposed radially by protruding from the surface of the rubber roll portion.

Furthermore, as described in Japanese Patent Publication No. 62-92011, for example, rollers with a low coefficient of friction in which fibers are bonded radially on a core metal are also known; Sometimes, the disadvantage is that the fibers easily fall off when they repeatedly come into contact with conveyed objects or belts.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a short fiber mixed roller that can easily manufacture a short fiber mixed roller in which short fibers are oriented in the radial direction.

(Means for Solving the Problems) The present invention is based on a method for manufacturing a rubber roller containing short fibers, in which a rubber roll part is fitted onto a core metal, and short fibers are oriented in the radial direction in the rubber roll part. A long rod with a circular cross section is inserted into the center of the molding space of a molding mold having a circular molding space and an annular dam portion formed on the molding surface, and an elastomer mixed with short fibers is supplied into the molding space. While forming a cylindrical roll material around the long rod, the elastomer and the long rod are supplied in the extrusion direction and cured by vulcanization, and the vulcanized and hardened roll material is made into a predetermined size. The structure is such that a rubber roll portion is formed by cutting, and then a core bar is inserted into the rubber roll portion, and the surface of the rubber roll portion is subjected to surface treatment.

(Function) According to the present invention, a long rod having a circular cross section is inserted into the center of the molding mold having a molding space having a circular cross section and an annular dam portion formed on the molding surface.

Then, while supplying the elastomer mixed with short fibers into the molding space to form a cylindrical roll member material around the long bar, the elastomer and the long bar are fed in the extrusion direction, and vulcanization is cured. let A rubber roll part is formed by cutting the roll part material after vulcanization and hardening into a predetermined size, and then a core metal is inserted into the rubber roll part, and the surface of the rubber roll part is treated.

This produces a short fiber-containing rubber roller in which the short fibers are oriented in the radial direction.

(Example) Embodiments of the present invention will be described in detail below with reference to the drawings.

First, a mold 1 used in the method of the present invention for manufacturing a short fiber-containing rubber roll in which a rubber roll part is fitted onto a core metal and short fibers are oriented in the radial direction in the rubber roll part is shown in FIG. As shown, it has a molding space 1a with a circular cross section, and the unvulcanized short fiber-containing elastomer is introduced into the molding space 1a through a screw portion 4 formed by a feeding screw 3 disposed in a hollow adapter 2. 5 is now supplied.

Further, an annular dam portion 6 having an inner diameter smaller than the inner diameter of the molding space 1a and a predetermined length in the axial direction (extrusion direction) is formed to protrude from the molding surface of the molding space 1a.

At the same time, a long rod 7 is inserted into the center of the molding space 1a of the mold 1, and the long rod 7 is continuously fed in the extrusion direction together with the elastomer mixed with short fibers to be molded around it. It looks like this.

A heating furnace 8 is connected next to the mold 1 in the extrusion direction.

To manufacture a rubber roller using the mold 1, first, the long rod 7 is inserted into the center of the mold 1 and continuously fed in the extrusion direction. At the same time, the unvulcanized short fiber-containing elastomer 5 is supplied from the screw portion 4 between the mold 1 and the long rod 7. The short fiber-containing elastomer 5 moves in the extrusion direction together with the long rod 7 while forming a cylindrical roll material that will become a rubber roll around the long rod 7, and has an inner diameter smaller than the inner diameter of the molding space 1a. By passing through the dam part 6 as a constriction part, short fibers (not shown) in the elastomer are oriented in the flow direction (extrusion direction).

Then, the cross-sectional area narrowed by the dam part 6 is rapidly expanded and changed back to the cross-sectional area by the molding space 1a, thereby changing the orientation of the short fibers and causing them to be oriented radially.

In this way, the extruded short fiber-containing elastomer 5
By continuously passing through the heating furnace 8 adjacent to the mold 1, the long rod 7 is vulcanized and hardened following the molding.

In this way, extrusion molding, vulcanization hardening, and cooling are performed continuously with the long rod 7 inserted, and then the long rod 7 is extracted from the roll material after vulcanization and hardening. The elongated rod 7 ensures the accuracy of the inner diameter of the center hole of the hollow cylindrical roll material to be formed.

Further, after removing the long rod 7, the cylindrical roll material is cut into a predetermined length to form a rubber roll part, a core metal (shaft member) is inserted into the center hole of the rubber roll part, and the rubber roll part is cut into a predetermined length. form.

Next, a detailed explanation will be given based on a specific example.

Meta-aramid staple fibers (2 denier, cut length 3III11) are mixed into the chloroprene rubber compound at a volume content of 10%, and the mixture is kneaded and stirred using an internal mixer to form unvulcanized An elastomer 5 containing short fibers is obtained.

This unvulcanized short fiber-containing elastomer 5 is formed into a ribbon by an extruder, and is fed into the screw part 4.

The long rod 7 is chrome-plated and has an outer diameter of 10 mm.

Use one with a length of 51 mm and insert it from the rear of the extruder in the extrusion direction. Then, the inner diameter of mold 1 is 18III11
The inner diameter of the first dam part 6 is 12aa+, and the elastomer 5 and the long rod 7 are simultaneously extruded by rotation of the screw.

Thereafter, the temperature near the inlet of the heating furnace 8 is controlled to 120°C, and the temperature near the exit thereof is controlled to 190°C, and the material extruded from the extruder is continuously put into the heating furnace 8 and vulcanized. Subsequently, it is poured into water and the rubber temperature is cooled to below 50°C.

After cooling, the long rod 7 is extracted and the cylindrical roll material is cut into a length of 260+em using a cutter knife to form a rubber roll part. The inner diameter of the center hole of this rubber roll portion can be set within the range of 9.3 to 9.8 am with high accuracy since the center hole is regulated by the long rod 7 during molding. This rubber roll portion is inserted into a core metal having an outer diameter of 10 mm to obtain a short fiber-containing rubber roll in which short fibers are oriented in the radial direction.

The short fiber-containing rubber roll according to the present invention can be used as: (i) a driving and driven roll for a photosensitive belt in a copying machine;
Used in rubber rolls for cleaners, paper feed rubber rolls, platen rolls, etc. In automated equipment, used as rubber rolls for conveying tickets, cards, etc., driving conveyor belts, rubber rolls for following, etc.

(Effects of the Invention) Since the present invention is configured as described above, it is possible to easily produce a fiber-mixed rubber roll in which short fibers are oriented in the radial direction, and since the short fibers are mixed in the rubber roll portion, The short fibers are less likely to fall out during use, and can provide stable friction coefficient characteristics over a long period of time.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a sectional view of a mold used for manufacturing a rubber roll containing short fibers. 1... Molding mold 5... Elastomer mixed with short fibers 6...
Dam part 7... Long rod

Claims (1)

[Claims] (1) A method for manufacturing a short fiber-containing rubber roller in which a rubber roll part is fitted onto a core metal, and short fibers are oriented in the radial direction in the rubber roll part, and has a molding space with a circular cross section and a molding surface. A long rod with a circular cross section is inserted into the center of the molding space of a mold in which an annular dam part is formed, and an elastomer containing short fibers is supplied into the molding space to form a cylindrical shape around the long rod. The elastomer and the long rod are supplied in the extrusion direction while forming the roll material, and are cured by vulcanization.The roll material after vulcanization and hardening is cut to a predetermined size to form a rubber roll part, and then A method for producing a short fiber-containing rubber roller, which comprises inserting a core metal into a rubber roll portion and subjecting the rubber roll portion to surface treatment.