JPH0227066B2 - - Google Patents

Description

Detailed Description of the Invention A. Object of the Invention (1) Industrial Field of Application The present invention relates to a method for producing a fiber reinforced connecting rod, in particular having pin holes parallel to each other at the large end and the small end, and The present invention relates to a method for manufacturing a fiber-reinforced connecting rod in which an inorganic fiber molded body extending in the longitudinal direction of the rod is embedded.

(2) Prior art In manufacturing the fiber-reinforced connecting rod mentioned above, the first step is to cast a connecting rod material using a mold having a cavity for forming the connecting rod, and then the connecting rod material is taken out from the mold and machined to form the connecting rod material. A second step of drilling the pin holes at both ends of the wire is conventionally known.

(3) Problems to be Solved by the Invention When carrying out the above conventional method, especially in the first step, there is a problem that it is not easy to stably set the above inorganic fiber molded article in a fixed position in the mold cavity. It was hot.

Further, after the molten metal as a matrix was injected into the cavity, the entire molten metal was simply pressurized directly using a pressure punch outside the cavity, which caused the following problems. In other words, the molten metal injected into the cavity is cooled by the mold over time and becomes semi-solidified, increasing its viscosity and flow resistance. Even if pressure is applied, the pressure cannot be efficiently propagated to every corner of the cavity, and it is particularly difficult for the molten metal to sufficiently penetrate into the fine gaps between the fibers of an inorganic fiber molded product. Therefore, fiber reinforcement cannot be performed accurately.

The present invention has been proposed in view of the above, and provides a method for manufacturing a fiber-reinforced connecting rod, which can solve all of the above-mentioned problems of the conventional method, and also allows easy machining of pin holes in the second step. The purpose is to

B. Structure of the invention (1) Means for solving the problem In order to achieve the above object, the present invention has pin holes parallel to each other at the large end and the small end,
In addition, in manufacturing a fiber-reinforced connecting rod in which an inorganic fiber molded body extending in the longitudinal direction is embedded in the rod portion, a first step of casting a connecting rod material using a mold having a cavity for forming the connecting rod;
A method for producing a fiber-reinforced connecting rod, the method comprising: taking out the connecting rod material from a mold and drilling the pin holes at both ends of the connecting rod material by machining. The mold is used in which a pair of set pins extending substantially on the same line with respect to the space are fixed in a space corresponding to the space, and the first step includes:
By press-fitting both ends of the fiber molded body into a pair of opposing notches formed at the tips of the pair of set pins, the fiber molded body is passed longitudinally through the rod molded portion of the cavity. a process of positioning and holding the entire molten metal as a matrix injected into the cavity;
After the step of temporarily applying pressure with an overall pressure plunger provided outside the cavity, and after the start of pressure application with the overall pressure plunger, a pair of local pressure punches arranged to face each of the set pins, The method is characterized in that it includes a step of secondarily pressurizing the molten metal in the cavity by thrusting into the spaces corresponding to the respective pin holes of the cavity.

(2) Effect By simply press-fitting both ends of the inorganic fiber molded article into the notches at the ends of both set pins, the fiber molded article can be stably supported at both ends within the cavity. The setting operation to the internal cavity position of the body can be carried out extremely easily, quickly and accurately.

In addition, the molten metal injected into the cavity is first pressurized by the overall pressure plunger, and then, as time passes, the molten metal becomes semi-solidified and has increased viscosity and flow resistance, and the molten metal corresponds to each pin hole in the cavity. The semi-solidified molten metal, in which the pressure of the entire pressurizing plunger is difficult to propagate, is directly pressurized by the local pressurizing punch in the space where the molten metal is applied, and the molten metal is transferred to the fine spaces between the fibers of the fiber molded body. can be penetrated sufficiently and quickly. In addition, even in such a casting process, since both ends of the fiber molded body are firmly held in the notches of both set pins, there is no risk of the fiber molded body moving unintentionally within the cavity even if it is subjected to large molten metal pressure. In addition, even if the pressing force from the local pressure punch is concentrated on both ends of the fiber molded article, both ends can be firmly received by the set pins facing the local pressure punch, and the fiber Since there is no possibility that the pressing force of the local pressure punch will act on the molded article as a large bending load or buckling load, it is also effective in preventing deformation of the fiber molded article.

Furthermore, after being removed from the mold, the connecting rod material will have traces of both set pins and local pressure punches left on both ends, but these traces will be automatically removed by the subsequent machining of the pin holes. Since it disappears, it does not damage the appearance of the outer surface of the stove in any way.In fact, when machining the pin hole, it can be used as a pilot hole to determine the machining position, and the cutting process is performed by the volume of the extraction trace. The amount can be reduced.

(3) Embodiment An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 show a fiber-reinforced connecting rod 1 for an internal combustion engine obtained by the method of the present invention, and this connecting rod 1 is made of a connecting rod material 7 cast using an alloy such as an aluminum alloy as a matrix.
(Figure 3) is obtained by subjecting it to predetermined machining.
The cooking stove 1 consists of a rod part 2, a large end part 3 connected to one end of the rod part 2, and a small end part 4 connected to the other end of the rod part 2. A large diameter pin hole 5 is formed in the large end 3, and a small diameter pin hole 6 parallel to the pin hole 5 is formed in the small end 4. In addition, the entire rod portion 2 and a portion of the large and small end portions 3 and 4 connected to both ends thereof are fiber-reinforced with a rod-shaped inorganic fiber molded body F such as a metal fiber embedded therein, and the inorganic fiber molded body is Both end faces of F are large and small end holes 5,
They are exposed on the inner peripheral surfaces of 6, respectively.

4 and 5 show a casting apparatus for a connecting rod material 7, in which a mold 11 as a mold consisting of an upper mold 9 and a lower mold 10 is disposed on a base 8. As shown in FIG. The lower mold 10 is fixed to a base 8, while the upper mold 9 is fixed to a holder 12 that moves up and down by a hydraulic mechanism (not shown) or the like. A connecting rod material molding cavity 13 is formed between the opposing surfaces of the upper mold 9 and the lower mold 10, and the cavity 13 has a large end molding part 14, a small end molding part 15, and a space between the two molding parts 14 and 15. It consists of a rod part molding part 16 located in. Also, the small end molding part 1
5 communicates with an overflow portion 17 formed between opposing surfaces of the upper mold 9 and the lower mold 10. In the large end molding section 14 and the small end molding section 15, cylindrical spaces B ₁ and B ₂ corresponding to the pin holes 5 and 6 are formed with a diameter smaller than that of each pin hole 5 and 6, and
First and second set pins 18 ₁ and 18 ₂ located substantially on the same axis with respect to B ₁ and B ₂ protrude from the lower mold 10. On the upper surface of both set pins 18 ₁ and 18 ₂ ,
Notches 19 ₁ and 19 ₂ having a U-shape in plan are formed so that their open sides can face each other for fitting the inorganic fiber molded body.

A cavity 13 is provided in the upper die 9 and the holder 12.
The spaces B ₁ and B ₂ corresponding to the respective pin holes 5 and 6 of
First to third local pressurizing punches 20 ₁ to 20 ₃ , which respectively enter the space in the overflow portion 17 and directly pressurize the molten metal in the space and its surroundings, are slidably moved up and down. The first and second local pressure punches 20 ₁ and 20 ₂ are the first and second set pins 1
The punches 20 _{1 and 20 2 are arranged to face the upper surfaces of the punches 8 1 and} 18 ₂ , respectively, and the diameters of the punches 20 1 and 20 ₂ are slightly smaller than the diameters of the corresponding pin holes 5 and 6. are arranged to coincide with the axes of the first and second set pins 18 ₁ and 18 ₂ .

A sprue 21 communicates with the large end molded portion 14, and a whole pressurizing plunger 22 whose upper end surface faces the sprue 21 is slid onto the base 8. Therefore, the entire pressurizing plunger 22 is provided outside the cavity 13 and can temporarily pressurize the entire molten metal in the cavity 13 via the molten metal in the sprue 21.

In the casting operation, the upper mold 9 is raised and opened, and the inorganic fiber molded product F having a desired bulk density is placed in the rod molded part 16 of the cavity 13.
are arranged so as to run longitudinally, and both ends are connected to spaces corresponding to each pin hole of the cavity 13.
B ₁ and B ₂ are forcibly press-fitted into the notches 19 ₁ and 19 ₂ of both set pins 18 ₁ and 18 ₂ , respectively, thereby cross-linking the inorganic fiber molded body F between both set pins 18 ₁ and 18 ₂ . It can be held in the state. In this case, the length of the set pins 18 ₁ , 18 ₂ protruding from the lower die 10 and the notches 19 ₁ , 19 ₂
Due to the height position of the inorganic fiber molded body F, the inorganic fiber molded body F is arranged at the center of the rod molded part 16 of the cavity 13 with a space between it and the wall surface, and the diameter of the inorganic fiber molded body F is 19 ₁ , 19 ₂ and the length of the inorganic fiber molded body F is formed slightly longer than the interval between both notches 19 ₁ , 19 ₂ , so that the inorganic fiber molded body F is both notches 19 ₁ , 19 ₂ of both set pins 18 ₁ , 18 ₂
held firmly in between.

Thereafter, the upper mold 9 is lowered and polymerized to the lower mold 10 to close the mold, and a molten metal such as an aluminum alloy as a matrix is poured into the sprue 21 from a pouring spout (not shown). Then, the entire pressure plunger 22 is raised to push the molten metal into the cavity 13, and the entire molten metal in the cavity 13 is temporarily pressurized through the molten metal in the sprue 21. The molten metal in the cavity 13 is gradually cooled by the mold 11 and changes from a molten state to a semi-solidified state, and its viscosity and flow resistance increase, making it difficult for the pressurizing force of the overall pressure plunger 22 to propagate to every corner of the cavity 13. However, under such conditions, the first and second local pressure punches 20
₁ and 20 ₂ are lowered and plunged into the spaces B ₁ and B ₂ corresponding to the respective pin holes 5 and 6 of the cavity 13,
When the molten metal in and around the space is directly pressurized, the molten metal sufficiently penetrates between the fibers of the inorganic fiber molded body F even though it is in a semi-solidified state, so that the inorganic fiber molded body F and the matrix are bonded together. Definitely combined.

In this case, since the cavity is formed around the inorganic fiber molded body F in the rod molded part 16 of the cavity 13, the molten metal permeates from substantially the entire outer peripheral surface of the molded body F. If the third local pressing punch ₂₀₃ is also lowered during the local pressurization and pressurizes the molten metal in the overflow part 17, the inorganic fiber molded article F
The filling efficiency of molten metal can be further improved.

The pressurized state is maintained until the molten metal is completely solidified. When localized pressure is applied to the semi-solidified molten metal as described above, the applied pressure can be applied sufficiently to the molten metal that is in the process of solidification and contraction, thereby preventing the formation of shrinkage cavities in the matrix. can.

The stove material 7 shown in Fig. 3 is produced by the above method.
is cast, and in this casting process, the inorganic fiber molded body F has both ends attached to both set pins 18 ₁ ,
It is stably held at 18 ₂ and does not shift in position.

Next, the upper mold 9 is raised to open the mold, and the connecting rod material 7 is taken up from the lower mold 10. Traces of the set pins 18 ₁ and 18 ₂ are left on one side of both ends of the cooking rod material 7, and traces of the pressure punches 20 ₁ and 20 ₂ are left on the other sides.

Thereafter, the pin holes 5, 6 are machined on both ends of the connecting rod blank 7 using, for example, a drill, thereby obtaining the connecting rod 1 shown in FIG. In addition, during the above machining, the set pins 18 ₁ , 18 ₂ or the pressure punch 20
It is possible to use the sampling marks of ₁ and 20 ₂ as pilot holes for determining the machining position, and the amount of machining can be reduced by the volume of the sampling marks.

In the above embodiments, the process of casting the connecting rod material 7 constitutes the first step of the present invention, and the process of machining the pin holes 5 and 6 in the connecting rod material 7 constitutes the second step of the present invention. .

C Effects of the Invention As described above, according to the present invention, the fibers have pin holes parallel to each other at the large end and the small end, and an inorganic fiber molded body extending in the longitudinal direction is embedded in the rod. In manufacturing reinforced cooking stove,
A first step of casting a connecting rod material using a mold having a cavity for forming a connecting rod, and a second step of taking out the connecting rod material from the mold and drilling the pin holes at both ends of the connecting rod material by machining. In the method for producing a fiber-reinforced connecting rod, the cavity includes:
The mold is used in which a pair of set pins extending substantially on the same axis with respect to the space is fixed in a space corresponding to each of the pin holes, and the first step includes forming a pair of set pins at the tips of the pair of set pins. a step of press-fitting both ends of the fiber molded body into a pair of facing notches, thereby positioning and holding the fiber molded body at a position passing longitudinally through the rod molded portion of the cavity; In the process of temporarily pressurizing the entire molten metal as a matrix injected into the cavity by a total pressure plunger provided outside the cavity, and after the start of pressurization by the total pressure plunger, the molten metal is placed so as to face both set pins, respectively. The method includes the step of inserting a pair of local pressure punches into the spaces corresponding to the respective pin holes of the cavity to secondarily pressurize the molten metal in the cavity. By simply press-fitting both ends of the fiber molded article into the notches, the fiber molded article can be stably supported on both ends within the cavity, thus making it easier to set the fiber molded article in a fixed position within the cavity. This can be done extremely easily, quickly and accurately.

In addition, the molten metal injected into the cavity is first pressurized by a general pressure plunger, and then the molten metal, which becomes semi-solidified over time and has increased viscosity and flow resistance, is applied to each pin hole in the cavity. Since the space can be directly pressurized by a local pressure punch, the semi-solidified molten metal, in which the pressure of the overall pressure plunger is difficult to propagate, can be applied to the fine gaps between the fibers of the fiber molded body.
The matrix and the fiber molded article can be combined efficiently and precisely by allowing the matrix to penetrate sufficiently and quickly. Also, in this casting process,
Since both ends of the fiber molded article are firmly held in the notches of both set pins, there is no risk of it moving inadvertently within the cavity even when subjected to large molten metal pressure. Even if the pressing force is concentrated on both ends of the fiber molded body, both ends can be firmly received by the above-mentioned two set pins facing the local pressure punch, and the local pressure punch can be applied to the fiber molded body. Since there is no risk that the applied force will act as a large bending load or buckling load, it is effective in preventing deformation of the fiber molded product. Coupled with the effect of being able to efficiently and accurately combine the fiber molded body with the fiber molded body, it is possible to obtain an extremely high quality fiber-reinforced connecting rod material in which the fiber molded body of a predetermined shape is composited at a predetermined portion of the rod portion.

Furthermore, after being removed from the mold, the connecting rod material has not only the removal marks of both local pressure punches but also the removal marks of both set pins on both ends of the material. Since the pin holes are automatically removed, the appearance of the outer surface of the stove is not damaged in any way.In fact, when machining the pin holes, they can be used as pilot holes to determine the machining position, and the volume of the pin holes The amount of cutting work can be reduced by that amount, contributing to improved work efficiency and savings in matrix material.

[Brief explanation of drawings]

Fig. 1 is a plan view of the conrod, Fig. 2 is a cross-sectional view taken along the - line in Fig. 1, Fig. 3 is a cross-sectional plan view of the conrod material, Fig. 4 is a longitudinal sectional view of the casting device for conrod material, and Fig. 5 is a sectional view taken along the line in FIG. B ₁ , B ₂ ... Space corresponding to the pin hole of the cavity, F ... Fiber molded body, 2 ... Rod section, 3 ... Large end, 4 ... Small end, 5, 6 ... Pin Hole, 7...
Conrod material, 11...Mold as mold, 1
3... Cavity, 16... Rod molded part, 18 ₁ ,
18 ₂ ... Set pin, 19 ₁ , 19 ₂ ... Notch,
20 ₁ , 20 ₂ ... Pressure punch, 22 ... Overall pressure plunger.

Claims (1)

[Scope of Claims] 1. A fiber having pin holes 5, 6 parallel to each other in the large end 3 and small end 4, respectively, and in which an inorganic fiber molded body F extending in the longitudinal direction is embedded in the rod 2. In manufacturing a strengthened connecting rod, the first step is to cast the connecting rod material 7 using a mold 11 having a cavity 13 for forming the connecting rod, and then the connecting rod material 7 is taken out from the mold 11 and machined to form both ends of the connecting rod material 7. a second step of drilling the pin holes 5, 6 in the cavity 13, spaces _B1 , B corresponding to the pin holes 5, 6 in the cavity 13; A pair of set pins 18 extending substantially on the same axis with respect to the spaces B ₁ and B ₂ within the space B 1 and B 2 _.
The mold 11 in which the set pins _{18 1} , 18 ₂ are fixed is used, and the first step is performed by fixing the pair of set pins 18 ₁ , 1
By press-fitting both ends of the fiber molded body F into a pair of opposing notches 19 ₁ and 19 ₂ formed at the tips of the fiber molded bodies F, the fiber molded body F is inserted into the rod of the cavity 13 _. Part molding part 16
a step of positioning and holding the molten metal in a longitudinal position; a step of primarily pressurizing the entire molten metal as a matrix injected into the cavity 13 by an overall pressurizing plunger 22 provided outside the cavity 13; and a step of pressurizing the entire molten metal. After the plunger 22 starts applying pressure, a pair of local pressure punches 20 ₁ , 20 ₂ arranged to face the set pins 18 ₁ , 18 ₂ , respectively, are inserted into the respective pin holes 5 , 6 of the cavity 13 . and secondarily pressurizing the molten metal in the cavity 13 by plunging into the spaces B ₁ and B ₂ corresponding to the cavity 13, respectively.
A method for manufacturing fiber-reinforced conrod.