JPS6270017A - Manufacture of fiber reinforced plastic rocker arm - Google Patents

Abstract

PURPOSE:To distribute reinforcing fibers nearly uniformly by a method wherein an insert member is arranged within a molding tool in such a state that the reinforcing fibers are scatteringly interposed among a plurality of fiber position controlling parts and, after that, molten plastic material is injected in the molding tool for molding. CONSTITUTION:First, an insert member 10 onto which fiber position controlling parts are provided is arranged in a molding tool 16 by inserting a core 14 in the member 10. In this case, comparatively large quantities of reinforcing fibers 20 are arranged on the outer peripheral part side of the insert member 10 in such a manner as to connect a position to form the camshaft side end of a rocker arm to be obtained with a position to form its suction or exhaust valve side end. Secondly, molten plastic material 22 is injected through an injection port 18 into the molding tool 16. Finally, a rocker arm molding S with the desired shape is obtained by being formed in the state that the reinforcing fibers 20 are imbedded with nearly uniform density in the various portions of solidified plastic material 22' by cooling the molding tool 16 in order to solidify the molten plastic material 22 after the molten plastic material 22 is injected into the molding tool 16.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a rocker arm, which is a component of a valve train in an engine, made of fiber-reinforced plastic (hereinafter referred to as "F").
RP).

(Prior Art) The rocker arm, which is a constituent member of the -FJI valve mechanism of an engine, swings about the rocker arm shaft and transmits the movement of the cam surface of the camshaft to the intake valve or exhaust valve has been conventionally used. It is generally manufactured from metal materials such as cast iron or aluminum alloy.

However, rocker arms made of metal materials have a relatively large weight, which makes them unsuitable for reducing the weight of the engine, and their inertia is large, making them difficult to improve engine responsiveness. This is one of the obstacles.

For this reason, a lightweight rocker arm made of FRP has been proposed, as disclosed in, for example, Japanese Utility Model Application Publication No. 56-103610. As one method for manufacturing such FRP rocker arms, as shown in the above publication, prepreg plates made of reinforcing fibers impregnated with plastic material are processed into a predetermined shape and laminated, and then heated. It is known that press molding is performed under

However, when such a manufacturing method is adopted to manufacture a rocker arm, production efficiency is lowered due to the laborious work involved in processing the prepreg plate, and as a result, the manufacturing cost of the rocker arm increases. There is a problem with putting it away.

Therefore, when building the FRP Rosso Locker arm,
A large number of reinforcing fibers (long fibers) are placed in advance in a mold at predetermined positions (for example, to tie both ends of the rocker arm to be obtained), and molten plastic is placed in the mold where the reinforcing fibers are placed. Consideration is being given to adopting a method of injecting and molding materials (hereinafter referred to as injection molding method for cars).

(Problems to be solved by the invention) However, when such injection molding method is adopted, FR, P
When manufactured rocker arms are manufactured, the injection pressure (flow pressure) of the molten plastic material causes the reinforcing fibers placed in the mold to move undesirably and become biased. If the rocker arm is not utilized effectively, the strength of the molded rocker arm tends to be insufficient, which tends to cause problems.

In view of these points, the present invention aims to prevent the reinforcing fibers placed in the mold from being uneven when the reinforcing fibers are placed in the mold and then the molten plastic material is injected into the mold for molding. FRP that is fully reinforced with fibers and can be used to prevent oxidation. ! i! An object of the present invention is to provide a method for manufacturing an FRP rocker arm that can efficiently obtain a rocker arm.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the FRP rocker arm manufacturing method according to the present invention includes a rocker arm shaft that receives a rocker arm shaft that is provided with a plurality of fiber position regulating parts on the outer periphery. An insert member that forms a bearing part is obtained, and this insert member is placed in a mold with reinforcing fibers dispersed and interposed between a plurality of fiber position regulating parts, and then a molten plastic material is poured into the mold. It includes the steps of injecting and molding.

(Function) The FRP according to the present invention as described above! ! ! ! In the rocker arm manufacturing method, when the molten plastic material is injected into the mold, the reinforcing fibers in the mold are restrained by a plurality of fiber position regulating parts provided in the insert member. Therefore, a situation in which the reinforcing fibers are undesirably moved within the mold due to the injection pressure and become lopsided can be avoided.

As a result, the reinforcing fibers are distributed approximately evenly, resulting in an FRP rotor rocker arm that is sufficiently reinforced by the fibers.

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

When implementing an example of the FRP rotor rocker arm manufacturing method according to the present invention, first, an insert member 10 as shown in FIG. 1 is prepared. This insert member lO
, which forms a bearing portion for receiving the rocker arm shaft, is made of a cylindrical shape from a wear-resistant metal material, and has a plurality of fin-shaped fiber position regulating portions 12 arranged in parallel on its outer periphery. . These fiber position regulating portions 12 are plate-shaped bodies that are integrally formed with the insert member 10 and protrude in the radial direction of the insert member 10 at predetermined intervals.

Next, as shown in FIGS. 2 and 3, the core 14 is inserted into the insert member 10 provided with the fiber position regulating portion 12 as described above, and placed in the mold (cavity) 16. At this time, a relatively large amount of reinforcing fibers (long fibers made of carbon fiber, glass fiber, etc.) 20 are placed on the outer peripheral side of the insert member 10 placed in the mold 16, and the cam of the rocker arm to be obtained is It is arranged so as to connect the position on the shaft side and the position on the intake or exhaust valve side. At this time, a predetermined amount of the reinforcing fibers 20 are interposed between each fiber position regulating part 12 of the insert member 10 placed in the mold 16.

The mold 16 is made up of, for example, a movable mold 16A and a fixed mold 16B, and has an injection port 18 at a predetermined position along the axial direction of the rocker arm to be obtained, that is, the axial direction of the insert member 10. is provided.

In this way, the reinforcing fibers 20
The molten plastic material 22 (the moving direction of which is indicated by the blank arrow in FIG. 3) is injected into the mold 16 from the injection port 18 with a predetermined amount of the plastic material 22 interposed therebetween. In this case, the injection pressure of the molten plastic material 22 acts to press the reinforcing fibers 20 along the axial direction of the insert member 10, but the fiber position regulating portion 12 provided on the outer circumference of the insert member 1° Since the movement of the reinforcing fibers 20 is regulated, the reinforcing fibers 20 are not biased in the mold 16.

After injecting the molten plastic material 22 into the mold 16, the mold 16 is cooled to solidify the molten plastic material 22, as shown in FIGS. 4 and 5.
A rocker arm molded body S having a desired shape is obtained by embedding the reinforcing fibers 20 in each part of the solidified plastic material 22 with substantially uniform density. Thereafter, the obtained rocker arm molded body S is subjected to predetermined machining and the like to obtain an FRP rotor rocker arm product.

Inside the FRP Rosolocker arm manufactured through the above process, the reinforcing fibers 20 are distributed approximately evenly without being extremely localized, so that they are perpendicular to the axial direction. The bending strength in the direction of
It has sufficient strength. Therefore, the FR is lighter than rocker arms made of metal materials.
The P-made rostro rocker arm has sufficient strength and can be manufactured much more easily than when a prepreg plate is used, thereby improving the production efficiency of the FRP rostro-locker arm.

Furthermore, since the insert member IO forming the bearing portion for receiving the FRP Rosolo rocker arm rocker arm shaft obtained in the above example is formed of a metal material,
It has excellent wear resistance, and furthermore, the fiber position regulating part 12 provided on the insert member 10 plays the role of a reinforcing member and increases the bonding strength between the insert member 10 and the solidified plastic material 22゛. This has the advantage of also serving as a guideline.

In addition, in the above-mentioned example, the fiber position regulating part 12 is formed integrally with the insert member 10;
The method for manufacturing an FRP floor car arm according to the present invention is not limited to this, but for example, as shown in FIG. The position regulating part 12' is manufactured separately,
A fiber position regulating part 12 is provided on the outer periphery of the insert member 10.
' may be press-fitted and fixed. Further, the fiber position regulating portion 12 or 12゛ can be formed not only in a plate shape but also in various shapes, for example, as a rod-shaped protrusion that protrudes radially from the outer circumference of the insert member IO or 10゛. Good too.

(Effects of the Invention) As is clear from the above description, according to the method for manufacturing an FRP rotor rocker arm according to the present invention, when manufacturing an FRP rotor rocker arm by injection molding of molten plastic, reinforcing fibers are It is possible to prevent undesired movement and skewing due to the injection pressure of molten plastic, and therefore it is possible to easily obtain an FRP rotor rocker arm with extremely high strength in which the reinforcing fibers are approximately evenly distributed. can. Further, by fully utilizing the advantages of injection molding of molten plastic, the production efficiency of FRP rotor rocker arms can be significantly improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an insert member used in carrying out an example of the FRP rotor rocker arm manufacturing method according to the present invention, and FIGS. FIG. 6, which is a diagram used to explain each manufacturing process of an example of the manufacturing method of Rosorocker arm, shows the FRP'M according to the present invention.
FIG. 7 is a cross-sectional view showing another example of an insert member used in implementing an example of the method for manufacturing a rocker arm. In the figure, 10 is an insert member, 12 is a fiber position regulating part,
16 is a mold, 18 is an injection port, 20 is a reinforcing fiber, and 22 is a molten plastic material.

Claims (1)

[Claims] An insert member forming a bearing part is provided with a plurality of fiber position regulating parts on the outer periphery, and the insert member is placed in a mold, and reinforcing fibers are dispersed and interposed between the plurality of fiber position regulating parts. A method for manufacturing an FRP rocker arm, which comprises placing the FRP rocker arm in the above-mentioned state, and then injecting a molten plastic material into the mold to mold the rocker arm.