JPS6383237A - Manufacture of cylindrical fibrous formed body for reinforcement - Google Patents

Abstract

PURPOSE:To improve the degree of dryness of undermentioned material and also to reduce the variance of thickness of a fibrous formed body and to improve surface characteristics, by exerting the sliding revolution of a pressure roller around a formed-body material, sucking action into a mold, and the injection of a hot blast from the above roller. CONSTITUTION:An air permeable cylindrical pattern 2 composed of shell sand is fixed on a rotary stand 8 of a roller press 7 and, while rotating the mold 2 counterclockwise, sucking action is applied to the inside of the mold 2 by means of a vacuum pump 11 via the rotary stand 8. On the other hand, while rotating, clockwise synchronously with the mold 2, the air permeable pressure roller 9 having numerous through holes 10 in the peripheral wall, a hot blast supplied from a compressor 12 via a heater 13 is jetted from the inside of the roller 9 toward the outside periphery. This roller 9 is moved forward toward the mold 2 and slidingly revolved along the outside peripheral surface of the formed-body material 6. In this way, the degree of dryness of the above material 6 is improved and handling property can also be improved.

Description

Detailed Description of the Invention A0 Object of the Invention (1) Industrial Application Field The present invention relates to a method for manufacturing a reinforcing cylindrical fiber molded body used for fiber reinforcing metal members, etc. A sealed, air-permeable cylindrical mold is immersed in an aqueous solution of a molding material containing reinforcing fibers and an inorganic binder, and suction is applied into the mold to spread the molding material around the outer periphery of the mold. a step of molding the molded body material by adhering it to a surface; a pressing step of pressing the molded body material against the mold to adjust the shape of the molded body material; a step of heating and drying the molded body material; The present invention relates to an improvement in a method using: firing a molded body material and partially bonding the reinforcing fibers with the inorganic binder.

(2) Prior art The applicant has proposed a method of performing this type of manufacturing using a rubber press (Patent Application No. 61-1
No. 1611).

(3) Problems to be solved by the invention In the rubber press, a mold is installed in a pressure-resistant container, and pressurized air is supplied from an air pressure source into the pressure-resistant container to move the molded material into the mold through the rubber. It is pressed against the outer circumferential surface of the

This rubber press dehydrates the molded material,
Furthermore, the wall thickness of the fiber molded body is determined, and as a result of various studies on the degree of dryness of the molded body material, variations in wall thickness, and surface properties of the fiber molded body, it was found that the rubber press has its own limitations. There was found.

In view of the above, the present invention uses a roller press instead of a rubber press to improve the degree of dryness of the molded body material, reduce variations in wall thickness of the fiber molded body, and improve surface properties. It is an object of the present invention to provide the above-mentioned manufacturing method.

B1 Structure of the Invention (1) Means for Solving Problems The present invention performs the pressing step by applying suction to the inside of the mold while rotating the mold, and at the same time applying suction to the outer peripheral surface of the molded body material. It is characterized in that it is carried out by blowing hot air from the inside of the press roller toward the outer periphery while slidingly rotating the press roller having air permeability.

(2) Effect: Due to the sliding rotation of the press roller against the molded body material, the suction action into the mold, and the jetting of hot air from the press roller,
The molded body material can be efficiently and sufficiently dehydrated, and its degree of dryness can be improved, making it easier to handle.

Furthermore, the thickness of the molded body material is regulated by the distance between the mold and the pressing roller, thereby reducing variations in the thickness of the fiber molded body. At the same time, the occurrence of wrinkles on the inner and outer peripheral surfaces of the molded body material can be avoided, and the surface properties of the inner and outer peripheral surfaces of the fiber molded body can be improved.

(3) Example FIG. 1 shows a reinforcing cylindrical fiber molded body 1 obtained according to the present invention. It is partially bonded by silica sol, alumina sol, or a mixed sol thereof, and has countless voids into which the matrix can penetrate.

This fiber molded body 1 is made of, for example, an aluminum alloy (JIS
When casting a cylinder block using ADC12 (equivalent to ADC12), it is used in combination with an aluminum alloy matrix to obtain a fiber-reinforced composite cylinder sleeve.

Next, a method for manufacturing the fiber molded body 1 will be explained with reference to FIG.

As shown in Figure 2(a), shell sand (grain size AFS35
) is used to form a cylindrical mold 2 having air permeability.

The mold 2 has an outer diameter of 75 mm, a wall thickness of about 5 N, and a radial crushing strength of 65 kg/c+a. Furthermore, since the mold 2 is made of shell sand, it has the property of collapsing when heated to 450°C.

As shown in FIG. 2 (bl), holders 31 and 32 are attached to the openings at both ends of the mold 2 by gluing, bolting, etc., and the openings are sealed.

As shown in FIG. 2 (0), the mold 2 is immersed in an aqueous solution 4 of a molding material containing alumina-silica fibers with a length of 25 to 1000 μm and alumina sol with a concentration of 5%, and the mold 2 is The molding material is adhered to a predetermined thickness on the outer circumferential surface of the mold 2 by applying suction so that the internal pressure becomes 200 to 600 Torr, and a molded body material 6 having a fiber volume percentage of 5 to 10% is molded.

As shown in Figure 2+d+, the mold 2 is moved to the roller press 7.
It is set up on a rotary table 8. A pressing roller 9 is disposed on the side of the mold 2 and parallel to it.

The pressing roller 9 has numerous through holes 10 in its peripheral wall to provide air permeability, and is movable forward and backward relative to the mold 2.

While rotating the rotary table 8, and therefore the mold 2, counterclockwise at a rotational speed of 20 rpm or less, a vacuum pump 11 applies suction into the mold 2 through the rotary table 8.

The pressure roller 9 is located at the position shown by the chain line in FIG. 2 (dl) and is spaced apart from the mold 2.
rpm or less, and while rotating clockwise in synchronization with the mold 2, the compressor 12 blows hot air that has passed through the heater 13 from the inside of the pressure roller 9 toward the outer periphery.

The pressing roller 9 is advanced toward the mold 2 and rotated to rub against the outer peripheral surface of the molded body material 6. In this case, the pressure roller 9
The forward speed of is determined by the distance between the mold 2 and the press roller 9 being the target wall thickness tm of the fiber molded body 1 plus 11 (t
+1) It is fast until it reaches ms, and then the interval between both 2.9 controls the wall thickness to be slow until it reaches the crane. By moving the pressing roller 9 forward at high speed in this manner, it is possible to improve the efficiency of the pressing operation and at the same time, the molded body material 6 can be quickly and roughly pressed. Further, by moving the pressing roller 9 forward at a very slow speed, the molded body material 6 can be subjected to precision press processing.

In the pressing process by the roller press 7, the pressing roller 9 slides and rotates against the molded body material 6, the suction action into the mold 2, and the hot air is ejected from the pressing roller 9, so that the molded body material 6 is dehydrated. This is carried out efficiently and sufficiently to the extent that the surface is semi-dry, thereby improving the degree of dryness and improving handling properties.

For example, when the volume of the molded body material 6 is 1300 m3, the molded body material 6 after molding contains approximately 140 g of water, but this decreases to approximately 60 g after roller press processing. After rubber press processing, it weighs about 80 g, which shows the excellent dehydration treatment by roller press processing.

Further, the thickness of the molded body material 6 can be regulated by the interval between the pressing rollers 9 of the mold 2, and variations in the thickness can be reduced. At the same time, the occurrence of wrinkles on the inner and outer peripheral surfaces of the molded body material 6 can be avoided and the surface properties of the inner and outer peripheral surfaces can be improved.

As shown in Figure 2+e), both holders 31 are removed from the mold 2.
．． 3 Remove □.

As shown in FIG. 2 (fl), the mold 2 is placed in a drying oven 14, and the molded body material 6 is subjected to a drying process at 120° C. for 1 hour to completely evaporate water.

As shown in FIG. 2(g), the mold 2 is placed in a firing furnace 5, and the mold 2 is subjected to a disintegration treatment at 450° C. for 30 minutes. The mold 2 is 100% collapsed by this collapse treatment.

As shown in FIG.
A firing treatment is performed at ℃ for 30 minutes. As a result, the alumina-silica fibers are partially bonded by the alumina sol, and the fiber molded body 1 shown in FIG. 1 is obtained.

FIG. 3 shows the degree of variation in the inner and outer diameters of the fiber molded body 1 obtained by the present invention and a fiber molded body obtained using a rubber press as a comparative example. The solid line a corresponds to the present invention, and the dotted line b corresponds to the comparative example.

As is clear from FIG. 3, the fiber molded product 1 obtained according to the present invention has less variation in wall thickness than that of the comparative example, and also has no wrinkles on the inner and outer peripheral surfaces. It has a good surface texture.

C1 Effects of the Invention According to the present invention, by employing the above-mentioned pressing step, the molded body material can be efficiently and sufficiently dehydrated, and its degree of dryness can be improved to improve handleability.

Further, it is possible to obtain a fiber molded article with less variation in wall thickness and improved surface properties.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a fiber molded product, FIG. 2 is an explanatory diagram of the manufacturing process of the fiber molded product, and FIG. 3 is a graph showing variations in the inner and outer diameters of the fiber molded product. J... Fiber molded body, 2... Molding die, 4... Aqueous solution, 5] 2... Lifting pump, 6... Molded body material, 8... Rotating table, 9... Pressing Roller, 11... Vacuum pump, 12
...Compressor, 13...Heater, 14...Drying furnace, 15 River firing furnace

Claims (1)

[Claims] A breathable cylindrical mold with both end openings sealed is immersed in an aqueous solution of a molding material containing reinforcing fibers and an inorganic binder, and a suction action is applied inside the mold to apply the molding material to the molding. A step of molding a molded body material by adhering it to the outer peripheral surface of a mold; a pressing step of pressing the molded body material against the mold to adjust the shape of the molded body material; a step of heating and drying the molded body material. and; a step of partially bonding the reinforcing fibers with the inorganic binder by firing the molded body material; In the method for producing a reinforcing cylindrical fiber molded body, the pressing step is performed by rotating the mold. This is carried out by applying suction to the inside of the mold while rotating the molded body material, and blowing hot air from the inside of the pressing roller toward the outer periphery while sliding and rotating an air permeable pressing roller on the outer peripheral surface of the molded body material. A method for producing a reinforcing cylindrical fiber molded article, characterized in that: