JPS59125261A - Mold for molten metal forging - Google Patents

Abstract

PURPOSE:To support surely a reinforcing member in dies with excellent operability by projecting downward the lower part of a top die in the part facing the cavity, and forming continuously the inside circumferential groove surface in an annular hollow groove for detaining the reinforcing member. CONSTITUTION:A reinforcing member 31 is placed in the hollow groove 33 of a bottom die 2 divided in a die open state and thereafter a top die 1 and the die 2 are clamped in the case of forming a reinforced piston. The member 31 is detained and supported in the groove 33 by clamping of the die 1 and the die 2, by which the die is loaded and set in the cavity 12. The loading and setting of the member 31 into the cavity 12 are thus accomplished by placing only approximately the lower half of the member 31 in the groove 33. The loading of the member 31 is thus accomplished more easily and quickly as compared to the prior art.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold for forging molten metal, and more particularly to a mold for molten metal forging, in which a reinforcing member made of metal fiber or the like can be charged and set in advance in a cavity.

Molten metal forging is generally used as a manufacturing method for pistons, connecting rods, etc. that make up internal combustion engines.
Particularly in the manufacture of pistons and the like, a reinforcing member made of metal fiber or the like is inserted and set into the cavity in advance to strengthen the piston ring groove.

Conventionally, this type of reinforced piston has the following characteristics, as shown in FIG.
A reinforcing member 54 is placed on the lower end of a cavity 53 formed by an upper mold 51 and a lower mold 52, and then molten metal is supplied into the cavity 53, and the upper mold 51 is moved completely downward to solidify under pressure. However, this method has disadvantages such as the position of the reinforcing member 54 fluctuating depending on the amount of poured molten metal and the workability of inserting the reinforcing member 54 into the cavity 53 is poor.

On the other hand, as a method for accurately molding products regardless of variations in the amount of poured molten metal, the molten metal is temporarily stored in a molten metal storage space.
There is a method in which molten metal is filled into a cavity through a runner and solidified under pressure by upward movement of a pressure granzer provided at the bottom of a hot water storage space.

However, to manufacture the reinforced piston in this way,
It is necessary to form the reinforcing member locking portion inside the cavity, and the reinforcing member locking portion must not have a structure that allows the reinforcing member to be moved or deformed by the molten metal flowing through the runner when filling the molten metal. In addition, the reinforcing member must have excellent workability when charging.

The present invention has been made in view of the above circumstances, and the object of the present invention is to store molten metal in the entire molten metal storage space from the pouring port, and to move the molten metal upwardly by a pressurized silane provided at the lower part of the molten metal storage space. A reinforcing member locking point that securely supports a reinforcing member in a mold for forging molten metal that is solidified under pressure after filling all cavities with molten metal through a runner, and has excellent reinforcing member charging workability. The purpose is to set up

In order to achieve the above object, the present invention forms an annular enclosure for locking a reinforcing member on the inner circumferential surface of the cavity and a portion including the mating surfaces of the upper mold and the lower mold, and also forms a runner to form a runner to connect the cavity. The lower part of the upper die of the portion facing the groove protrudes downward, and the inner circumferential groove surface of the groove is formed in a continuous shape.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below regarding a mold for molding a piston for an automobile engine.

FIG. 1 is a sectional view of the mold into which the reinforcing member is inserted, and FIG. 2 is a sectional view taken along the line I--■ in FIG. 1.

1 is the upper mold, 2 is the lower mold, and the upper mold 1 and the lower mold 2 are mating surfaces 3 and 4.
All 4 parts are molded.

A hole 5 for a hot water storage space is vertically formed through the lower mold 2, and a lower end of a pouring sleeve 7 into which a pouring plant 6 is fitted is opened at an appropriate location of the hole 5 for a hot water storage space. , a pressurized gland 8 slidably fitted into the hole 5 for the hot water storage space.
A hot water storage space 11 is constituted by the hot water storage space hole 5, the mating surface 3, and the continuous upper die lower surface 9.

A recess 13 is provided on the upper surface of the lower mold 2 to communicate the upper part of the hot water storage space 11 and the lower part of the product cavity 12, and a runner 14 is formed between the recess 13 and the lower surface 9 of the upper mold. A downwardly inclined surface 15 that gradually projects downward as it approaches the cavity 12 is formed at a portion of the lower surface 9 of the upper mold, which constitutes the entire runner 14, near the cavity 12.

The cavity 12 includes: - a cavity hole 21 penetrating through the upper mold 1; an insert member 22 suspended in the cavity hole 21; It is composed of a cavity recess 23 provided therein.

The runner 14 is opened at the lower part of the inner circumferential surface 24 of the cavity recess 23, and a sliding hole 25 that extends vertically is opened in the center of the cavity recess 23. A secondary pressurizing gland 32 having an outer diameter smaller than the inner diameter of the reinforcing member 31 to be inserted is fitted.

An annular groove 33 for locking the reinforcing member 31 is formed in the lower part of the inner peripheral surface 24 of the cavity 12.

The annular groove 33 is located at the middle part of the groove 33 in the downward direction.
'' is formed so that the mating surfaces 3 and 4 of the second mold 1 and the lower mold 2 are located, the inner circumferential groove surface 34 is continuous in the circumferential direction, and the inclined surface 1
The lower end of 5 and the lower end of the inner circumferential groove surface 34 match, or substantially match.

The inner circumferential groove surface 34 of the annular groove 33 is opened at the lower end of an air vent hole 35 that extends obliquely upward and communicates with the outside air. Books provided.

Since the present invention is configured as described above, when molding a reinforced piston, the reinforcing member 31 is first placed in the groove 33 of the divided lower mold 2 with the mold opened, and then the reinforcing member 31 is placed in the groove 33 of the divided lower mold 2, and then the upper mold 1
and the lower mold 2 are clamped together.

By clamping the upper mold 1 and the lower mold 2, the reinforcing member 31 is formed into the groove 3.
3 and is supported and inserted into the cavity 12.

Therefore, the reinforcing member 31 is inserted into the cavity 12 by placing only the substantially lower half of the reinforcing member 31 into the groove 33. It can be done more easily and quickly than before.

Next, the pouring plunger 6 is placed in the upper part, the pressurizing plunger 8 is placed in the lower part, and the secondary pressurizing plunger 32 is appropriately placed in the lower part to pour a predetermined amount of molten metal from the pouring sleeve 7 into the hot water storage space. 11.

After supplying a predetermined amount of molten metal to the hot water storage space 11, the γ factory plant gear 6 is lowered and the pouring sleeve 7'c Iz-j
Then, the pressurizing plunger 8 is raised at a predetermined slow speed.

As the pressurized plant jar 8 rises, the molten metal stored in the hot water storage space 11 flows into the cavity 12 via the runner 14.

In this case, the reinforcing member 31 is supported by the groove 33, and the outer circumferential surface 31a of the reinforcing member 31 is entirely covered with the inner groove surface 34 of the groove 33, so that the reinforcing member 31 is reinforced by the molten metal flowing into the cavity 12. Displacement, deformation, etc. of the member 31 are prevented, and the molten metal (molten metal) flows smoothly into the cavity 12 due to the inclined surface 15.

After filling the cavity 12 with molten metal, the secondary pressurization plant 32
is raised and pressurized, and in this state the molten metal is completely solidified.

During pressurized solidification, the annular groove 33 forms the mating surface 3 of the upper mold 1 and lower mold 2.
, 4, and the air vent hole 35 is opened in the concave groove 33, so that even when a reinforcing member made of woven fibers or the like is used, the air in the reinforcing part 31' will not air. The molten metal is easily discharged out of the cavity 12 from the punching hole 35, and the fibers are easily impregnated with the molten metal. Therefore, the molten metal and the reinforcing member 31 can be more securely integrated, and it is possible to prevent the occurrence of flash on the split mold surface. is prevented.

After a certain period of time has elapsed, the mold is opened and the piston molded with a knockout bar (not shown) is taken out to obtain a reinforced piston to which the reinforcing member 31 is integrated.

What is shown in FIG. 3 is a second embodiment of the present invention. In the second embodiment, the lower surface 9 of the upper mold 1 constituting the upper surface of the pouring space 11 and the upper surface of the runner 14 is formed into an annular groove. 33 inner peripheral groove surface 34
This is different from the first embodiment in that it is uniformly formed to protrude downward to the lower end.9 It is easy to charge the reinforcing member 31, and there are no problems such as displacement or deformation of the reinforcing member 31 when filling the cavity 12 with molten metal. The preventing action, effect, etc. are the same as in the first embodiment.

As is clear from the above description, according to the present invention, the annular groove for locking the reinforcing member is formed in a part that includes the mating surfaces of the upper mold and the lower mold, and the inner circumferential groove surface is continuous. , the reinforcing member can be easily inserted and set into the cavity, and when filling the molten metal,
It exhibits excellent effects such as preventing displacement and deformation of the reinforcing member.

[Brief Description of the Drawings] Fig. 1 is a cross-sectional view of a mold according to the present invention, Fig. 2 is a cross-sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is a cross-sectional view of the second embodiment of the same. 4
The figure is a cross-sectional view of a conventional mold. In the drawing, 6 indicates a pouring plant jar, 18 indicates a pressurizing plant jar, 111 indicates a hot water storage space, 121rt indicates a cavity, and 14 indicates a hot water storage space.
(The runner is the runner, 31 is the reinforcing member, and 32 is the pressurized plant layer 1.
33 is an annular groove. Patent Applicant Honda Motor Co., Ltd. Agent Patent Attorney 2 1) Yong-Immediate Question Patent Attorney Kuni Ohashi Production Volume
Patent Attorney Yu Koyama 329

Claims (1)

[Claims] A cavity defined by an upper mold and a lower mold, a hot water storage space in which molten metal can be freely stored from a spout, and a runner that communicates the lower part of the cavity with the upper part of the hot water storage space,
In the mold for forging molten metal, in which the molten metal is filled into the entire cavity by upward movement of a pressure planter fitted in the molten metal storage space, and the molten metal is solidified under high hydrostatic pressure, An annular groove for locking the reinforcing part is formed in the part that includes the mating surfaces of the upper mold and the lower mold, and the inner periphery of the groove is made to protrude completely downward from the lower part of the upper mold in the part where the runner is fully formed and faces the cavity. A mold for forging molten metal characterized by a continuous groove surface.