JPS5814936B2 - Manufacturing method for fiber-reinforced resin leaf springs - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a glass or carbon fiber reinforced resin leaf spring used as a suspension leaf spring for an automobile.

Conventionally, leaf springs using reinforced plastic materials were developed to reduce the weight of vehicle parts.
6 and Japanese Patent Laid-Open No. 53-88449 are known.

The former, as shown in Japanese Utility Model Application Publication No. 51-132496, is
The eyeball part is formed integrally with the main body part, and the root part forming the eyeball part is welded to the end part of the main body, and furthermore, in order to prevent the welded joint part from peeling off, welding is done on the upper and lower surfaces of the welded part. It is secured with a metal plate and fixed with bolts, etc.

The latter, disclosed in Japanese Patent Application Laid-Open No. 53-88449, has an eye part formed of a metal plate separately from the main body part, and the eye part is fixed to the main body part with bolts or the like.

In this way, conventional reinforced plastic leaf springs have their eyelets fixed to the main body with bolts, etc., so bolt holes must be drilled in the main body, and the work of installing bolts requires a lot of man-hours. It has such drawbacks.

Furthermore, if the eyelet is integrated with the main body, it is very difficult to curl the eyelet and it takes a lot of effort to form it.

Further, even in the case where the other self-ball portion and the main body portion are separate, each must be molded separately, which similarly has the disadvantage that the molding process is labor-intensive.

The present invention was developed in view of the above-mentioned drawbacks of the prior art, and allows the eyepiece and main body to be integrally molded in mass production with few steps, has high strength, and can easily adjust the strength and load characteristics of desired types. An object of the present invention is to provide a method for manufacturing a reinforced resin leaf spring.

Hereinafter, the present invention will be explained with reference to illustrated embodiments.

A fiber wire such as carbon fiber or glass fiber is used as the material, and a plurality of these fiber wires are arranged in the form of a sheet and impregnated by immersing them in a thermosetting resin solution for an appropriate period of time.

The thermosetting resin solution is prepared by adding a certain amount of a curing agent such as methyl ethyl ketone peroxide and a curing accelerator such as cobalt naphthenate to a thermosetting resin, and mixing and stirring the mixture.

Moreover, polyester or epoxy resin is used as the thermosetting resin.

These resins have high tensile strength after molding and are excellent in performance, so they are suitable as spring materials.

Next, the single layer of sheet-like fiber impregnated with thermosetting resin and taken out is heated at a temperature of around 80°C for a certain period of time. As a result, the single layer of fiber is cured and the sheet layer of fiber impregnated with thermosetting resin is heated. can get.

The present invention uses this sheet layer to mold a leaf spring.

First, as shown in FIG. 1, two metal pins 1, 1 are arranged in parallel.

Next, as shown in FIG. 2, the sheet layer 2 formed as described above is wound around the pins 1, 1 by a certain number of times.

Subsequently, as shown in FIG. 3, an auxiliary plate 3 having a predetermined thickness and shape is inserted into the space between the pins 1, 1.

The auxiliary plate 3 may be a single layer of fibers impregnated with a thermosetting resin like the sheet layer 2, or may be a commonly used reinforced resin plate.

Next, as shown in FIG. 4, the sheet layers 2 are welded to each other and the sheet layer 2 and the auxiliary plate 3 are welded to each other and the center part 6 and the main body part are pressed together and then heated and hardened. A leaf spring 8 with an integrated T is obtained.

As is clear from the above description, according to the present invention, the sheet layer is wound around two pins, then an auxiliary plate is inserted between the two pins, and finally the sheet layer is pressed and heated. Therefore, it requires fewer steps and can be mass-produced.

In addition, the eye portions at both ends and the main body portion can be integrally molded, and there is no need to fix the eye portions with bolts or the like, reducing the number of man-hours.

Also, since the fibers are continuous and integrated, high strength can be obtained.

In addition, the strength and load characteristics can be easily adjusted to desired values by changing the number of windings of the sheet layer, the shape and material of the auxiliary plate, and other factors.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, FIG. 3, and FIG. 4 are process explanatory diagrams showing the manufacturing process of the glass fiber reinforced resin leaf spring according to the present invention. 1... Pin, 2... Sheet layer, 3... Auxiliary plate, 4
, 5... Mold, 6... Eyepiece, 7... Main body, 8
...leaf spring.

Claims (1)

[Claims] 1. Two pins are arranged in parallel with a constant interval, and with these pins as two axes, a sheet layer made of fibers such as glass impregnated with thermosetting resin is wound a certain number of times, and then the space between the pins is A method for manufacturing a fiber-reinforced resin leaf spring, which includes inserting an auxiliary plate, then press-forming with a mold, and then heating and curing.