JPH0434267A - Manufacture of piston pin - Google Patents

Abstract

PURPOSE:To provide endurance for long period use by arranging metal-made rings where shearing force is received in a clearance part between a piston and a connecting rod, and covering the outside of a fiber reinforced resin-made bar-shaped unit with a metal-made pipe. CONSTITUTION:A piston pin 1 has a fiber reinforced resin-made bar-shaped unit 2 of uniform external diameter in the center part, and metal-made rings 3a, 3b are arranged where large shearing force is received in a clearance part between a piston and a connecting rod, of this fiber reinforced resin-made bar- shaped unit 2. Reinforced fiber resin 4a, 4b, 4c provided by filament winding are provided in central and both side parts where metal-made rings 3a, 3b are not arranged, while the fiber reinforced resin-made bar-shaped unit 2 is covered with a metal-made pipe 5 through these metal-made rings 3a, 3b and reinforced fiber resins 4a, 4b, 4c.

Description

[Detailed description of the invention] [Purpose of the invention]

(Industrial Application Field) The present invention relates to a method for manufacturing a piston pin used for manufacturing a piston pin used to connect a piston and a connecting rod of an engine. (Prior Art) Conventionally, a piston pin has been used to connect an engine piston and a connecting rod. There are fixed types (for example, [New Edition Automotive Engineering Handbook No. 4 j9 >
(Published by Society of Automotive Engineers of Japan, September 30, 1981, pp. 1-78). In order to reduce the weight of this type of piston pin, as shown in FIG. Types were also developed. In such a composite piston pin 51, the fiber-reinforced resin rod 52 is made of, for example, carbon fiber-reinforced resin, and the resin used is a heat-resistant resin such as polyimide or polyamide-imide. The carbon mM was unidirectional and aligned along its length, and was also spirally wound by filament winding. On the other hand, the metal pipe 53 is made of the same material as the conventional metal piston pin, and its surface is carburized, but its thickness is thinner than that of the conventional metal piston pin. Then, by press-fitting the rod-shaped body 52 made of fiber-reinforced resin into a metal pipe 53, a piston pin 51 made of a composite of fiber-reinforced resin and metal was obtained. (Problem to be Solved by the Invention) However, in the piston pin 51 made of such a conventional composite of fiber reinforced resin and metal, the thickness of the metal pipe 53 is uniform, and the connecting Although a large shear stress is applied to the piston pin 51 due to the clearance between the rod and the piston, the thickness of that part is the same as the other parts, so the explosive force of the engine As shown in FIG. 6, the shear stress generated at the clearance between the piston and the connecting rod causes the piston pin 5 to
The surface of piston pin 51 undergoes abrasion deformation, leaving traces of compressive deformation 54 on the surface of piston pin 51, making it difficult to put it to practical use when considering long-term engine rotation. Solving such problems has been a challenge. (Objective of the Invention) The present invention was made in view of the above-mentioned problems in the prior art, and is designed to be resistant to deformation even when subjected to a large shear force by the clearance between the piston and the connecting rod, and to be suitable for long-term use. The aim is to provide a lightweight piston pin that is capable of withstanding heavy loads.

[Structure of the invention]

(Means for Solving the Problems) A method for manufacturing a piston pin according to the present invention. l! When manufacturing a piston pin in which a metal pipe is covered on the outside of a fiber-reinforced resin rod, a metal ring is placed in the portion of the fiber-reinforced resin rod that receives shearing force due to the clearance between the piston and the connecting rod. The present invention is characterized in that a metal pipe is placed over the outside of the fiber-reinforced resin rod-shaped body after the piston pin is installed. It is said that In an embodiment of the piston pin manufacturing method according to the present invention, the outer diameter of the fiber-reinforced resin rod-like body is uniform and smaller than the inner diameter of the metal pipe; A metal ring whose outer diameter corresponds to the inner diameter of the metal pipe is placed in the part of the body that receives shearing force due to the clearance between the piston and the connecting rod, and then no metal ring is placed. Reinforced fiber resin is wound around the outer periphery of the central portion and both side portions of the fiber-reinforced resin rod by filament winding or the like until the outer diameter is approximately the same as the outer diameter of the metal ring, and then the metal ring and the winding are performed. It is possible to have a configuration in which a metal pipe is placed on the outside of a fiber-reinforced resin rod-shaped body provided with reinforced AM resin, and in another embodiment, the outer diameter of the central portion of the fiber-reinforced resin rod-shaped body is made of metal. It has a large diameter corresponding to the inner diameter of the metal pipe, and has a small diameter smaller than the inner diameter of the metal pipe on both sides. After arranging a metal ring whose outer diameter corresponds to the metal pipe in the part of the rod-shaped body that receives shearing force due to the clearance between the piston and the connecting rod, a 1ain reinforced resin rod-shaped body without a metal ring is installed. Winding reinforced fiber resin around the outer periphery of both sides of the body by filament winding etc. until the outer diameter is approximately the same as the outer diameter of the metal ring 1
Next, a metal pipe may be placed over the outside of the fiber-reinforced resin rod-shaped body provided with the metal ring and the wound reinforced fiber resin. As the reinforcing fibers of the above-mentioned iii and ii reinforced resin rods and the reinforcing fibers of the reinforced #Ita resin wound by filament winding etc., carbon m fibers and other fibers suitable for various reinforcements are used, and metal The rings used are those that can withstand the shear force generated by the clearance between the piston and the connecting rod, and the metal pipes used are those that have improved wear resistance through surface hardening, for example. It can be selected as appropriate depending on the situation. (Operation of the Invention) According to the method for manufacturing a piston pin according to the present invention, since it has the above-mentioned configuration, the piston pin manufactured here has a large shear force due to the clearance between the piston and the connecting rod. The receiving part has a metal ring, and the inside of the metal pipe is made of fiber-reinforced resin, so it is lightweight but has excellent overall toughness. In addition to being able to withstand the large shear force exerted by the clearance between the piston and the connecting rod. (Example) Hereinafter, an example of the method for manufacturing a piston pin according to the present invention will be described based on the drawings. FIGS. 1 and 2 of the support are diagrams showing one embodiment of the present invention. As shown in FIGS. 1(a) and 1(b), the piston pin 1 manufactured in the first embodiment of the present invention has a rod-shaped body 2 made of fiber-reinforced resin with a uniform outer diameter in its center portion. , metal rings 3a and 3b are disposed in a portion of this fiber-reinforced resin rod-shaped body 2 that receives a large shear force due to the clearance between the piston and the connecting rod; Reinforced ta fiber resins 4a, 4b, 4c provided by filament winding are provided in the center portion and both side portions which are not provided, and these metal rings 3a, 3b and reinforced fiber resin 4a are provided.
, 4b and 4c, a metal pipe 5 is placed over the outside of the rod-shaped body 2 made of am-reinforced resin. The piston pin 1 shown in FIGS. 1(a) and 1(b)
In manufacturing, as shown in FIG. 2(a), a rod-shaped body 2 made of fiber-reinforced resin having an outer diameter smaller than the metal pipe 5 is produced by pultrusion molding. Next, as shown in FIG. 2(b), a portion of the man-reinforced resin rod-shaped body 2 that receives a shearing force due to the clearance between the piston and the connecting rod is
Metal rings 3a and 3b whose outer diameter corresponds to the inner diameter of the metal pipe 5 are provided and fixed by adhesive. Next, as shown in FIG. 2(C), a metal ring 3a,
A tape made of reinforcing fibers impregnated with a heat-resistant thermosetting resin is placed on the outer periphery of the center and both sides of the rod-shaped body 2 made of fiber-reinforced resin, which is not provided with ring 3b. Reinforced fiber resin 4a is made to have the same outer diameter as the metal rings 3a and 3b by winding it by filament winding or the like until it has the same or slightly larger outer diameter, heating and curing it, and cutting the surface. 4b and 4c are provided. Next, mI provided with the metal rings 3a, 3b and the winding reinforcing fiber resins 4a, 4b, 4c.
m A metal pipe 5 shown in FIG. 2(d) is placed on the outside of the rod-shaped body 2 made of reinforced resin. At this time, the metal pipe 5 is heated (for example, about 150'C!) to increase its diameter, and on the other hand, the resin part of the Mi fiber-reinforced resin rod 2 to be press-fitted inside is heated using dry ice or the like. If the metal pipe 5 and the fiber-reinforced resin rod-shaped body 2 are press-fitted in this state and then returned to room temperature, the piston 1 shown in FIGS. 1(a) and 1(b) will be As a result, the metal pipe 5 is in close contact with the resin part press-fitted inside and will not come off. For example, even if the piston pin 1 reaches about 150 degrees Celsius due to engine combustion, the metal pipe 5 will remain intact. There is no chance of leaving. Then, we applied the piston pin 1 manufactured here to an actual engine under the conditions where the maximum load is applied (approximately 600 rpm).
), even when repeated loads were applied, there was no deformation of the piston pin 1 in the clearance area between the piston and the connecting rod. 11. FIGS. 3 and 4 are diagrams showing other embodiments of the present invention. As shown in Figs.3 (a) and (b), the piston pin 1 manufactured in the second embodiment of the present invention has a rod-shaped body 2 made of fiber-reinforced resin whose center portion has a large diameter. , metal rings 3a and 3b are disposed in close contact with the large-diameter portion of the fiber-reinforced resin rod-shaped body 2 at a portion that receives a large shearing force due to the clearance between the piston and the connecting rod. ,
Fiber resin 4a, 4 reinforced by filament winding on both sides where metal rings 3a, 3b are not provided.
c, and a metal pipe 5 is placed on the outside of the m-fiber reinforced resin rod-shaped body 2 via these metal rings 3a, 3b and reinforced fiber resins 4a, 4c. The piston pin 1 shown in FIGS. 3(a) and 3(b)
In manufacturing, a rod-shaped body 2 made of fiber-reinforced resin having an outer diameter approximately equal to that of the metal pipe 5 is produced by bow molding, and then both sides are thinned by pressure processing, and then heated and hardened. As shown in FIG. 4 (Jl), a fiber-reinforced resin whose outer diameter at the center corresponds to the inner diameter of the metal pipe 5 and which is smaller on both sides than the inner diameter of the metal pipe 5 is used. A rod-shaped body 2 is obtained. Next, as shown in FIGS. 4(b-1) and 4(b-2), tapered metal rings 3a and 3b with one inner circumference are inserted from both sides of the fiber-reinforced resin rod-shaped body 2 to tighten the fibers. Metal rings 3a and 3b, the outer diameter of which corresponds to the inner diameter of the metal pipe 5, are disposed in a portion of the reinforced resin rod-shaped body 2 that receives shearing force due to the clearance between the piston and the connecting rod. Next, prepreg chives made of reinforcing fibers impregnated with resin are placed around the outer periphery of both sides of the fiber-reinforced resin rod-like body 2 on which the metal rings 3a, 3b are not provided.
After winding by filament winding or the like until the outer diameter becomes approximately the same as the outer diameter of point b, the outer surface is heated and hardened, and then the outer surface is cut to make the surface smooth as shown in FIG. 4(d). Subsequently, as shown in FIG.
4 (e) on the outside of the fiber-reinforced resin rod-shaped body 2 shown in (d).
By press-fitting and covering the metal pipe 5 shown in ), the piston pin 1 shown in FIGS. 3(a) and 3(b) is obtained. According to this embodiment, one side of the metal rings 3a and 3b is tapered, so that they are lighter than the metal rings 3a and 3b of the first embodiment.
This contributes to further weight reduction of the piston pin 1. Further, in this embodiment, the rod-shaped body 2 made of fiber reinforced resin has a large diameter at its central portion, and by applying the tapered portion of the metal rings 3a, 3b, which are tapered on one side, the metal rings 3a, 3b Since the positions of the metal rings 3a and 3b are determined, it is only necessary to insert the tapered metal rings 3a and 3b from both sides, thereby eliminating the need for positioning the metal rings 3a and 3b. When the piston pin 1 manufactured according to this example was applied to an actual engine and a shear core force was applied, no deformation occurred in the piston pin 1.

【Effect of the invention】

The method for manufacturing a piston according to the present invention is such that when manufacturing a piston pin in which a metal pipe is covered on the outside of a rod-shaped body made of fiber-reinforced resin, a clearance portion between the piston and a connecting rod of the rod-shaped body made of fiber-reinforced resin is A metal ring is placed at the part that receives shearing force, and then a metal pipe is placed over the outside of the fiber-reinforced resin rod, so it is lighter than a piston pin that is entirely made of metal. It has excellent toughness, and the clearance between the piston and connecting rod prevents deformation even when subjected to large shear forces, making it durable for long-term use. This brings about the remarkable effect of being a product.

[Brief explanation of drawings]

181 (a) and (b) are explanatory views of slopes and explanatory cross sections of a piston pin manufactured according to an embodiment of the present invention, and Figs. 2 (a) to (d) are views of the piston pin manufactured according to an embodiment of the present invention. FIGS. 3(a) and 3(b) are explanatory diagrams sequentially showing the steps of manufacturing the piston pin according to another embodiment of the present invention, and FIGS. 4(a) to (e)
) are explanatory diagrams sequentially showing the steps of manufacturing the piston pin shown in Figure 3, Figure 5 is an explanatory diagram of the slope of a conventional piston pin, and Figure 6 is an explanatory diagram showing the steps of manufacturing the piston pin in Figure 3.
FM is a slope explanatory view showing a conventional piston pin in a deformed state. DESCRIPTION OF SYMBOLS 1... Piston pin, 2... Fiber-reinforced resin rod-shaped body, 3a, 3b... Metal ring, 5... Metal pipe. Fig. 2 (F) Fig. 2 (b) 2nd tl (C) b C Fig. 1 Fig. 1 (b) 2 curved nails 11 fractional resin Fig. 4 (b-1) Fig. 4 (b-2) Figure 4 (C) Figure 4 (d

Claims (1)

[Claims] (1) When manufacturing a piston pin in which a metal pipe is covered on the outside of a fiber-reinforced resin rod, metal is attached to the portion of the fiber-reinforced resin rod that receives shearing force due to the clearance between the piston and the connecting rod. 1. A method for manufacturing a piston pin, comprising the steps of: disposing a ring made of fiber-reinforced resin, and then covering the outside of the rod-shaped body made of fiber-reinforced resin with a metal pipe.