JPH0645063B2 - Casting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is to install a heterogeneous or homogeneous piece preliminarily processed into a predetermined shape in a cavity for pouring, thereby integrally integrating the piece and the casting. The present invention relates to a method of casting a cast gurney to melt molten metal.

(Prior Art) As a conventional technology, there is one described in JP-A-56-39365.

That is, as shown in FIG. 4, a columnar cavity 2 for forming a cam shaft is formed in a mold 1, and a sprue 3 is formed in communication with one end (right end portion) of the cavity 2 in the axial direction of the cavity 2. A plurality of cam pieces 4 are spaced apart from each other.

As shown in FIG. 5, the cam piece 4 is formed in an annular shape and an egg shape, and a thick fixing piece 5 is formed on the inner peripheral portion of the cam piece 4 so as to project in a tooth shape in the axial direction. Piece 5
Are projectingly arranged in a direction orthogonal to the molten metal flow path 2a of the cavity 2.

Then, there is a method of pouring molten metal into the cavity 2 from the sprue 3 to integrally join the cam piece 4 with the casting through the fixing piece 5 as shown in FIG.

(Problems to be Solved by the Invention) In the above-mentioned conventional one, the cam piece 4 installed in the cavity 2 is injected into the cavity 2 and the piece 4
Since it was only heated by the molten metal for molding remaining on the (fixed piece 5), the heating time for the piece 4 to be immersed in the molten metal having a high temperature was short, and the contact portion (a) between the piece 4 and the molten metal was smoothly fixed. There was a drawback that it was difficult to do.

It is an object of the present invention to obtain a new cast-in-turn casting method that solves the above drawbacks.

(Means for Solving Problems) The present invention is configured as follows to achieve the above object.

That is, a cavity that communicates with the gate and an outflow path that communicates the end of the cavity to the outside are formed in the mold, and a piece formed in a predetermined shape is set in the cavity.
The molten metal poured from the spout is made to flow out of the outlet channel by a predetermined amount, and then the outlet channel is closed to fill the cavity with the molten metal.

(Operation) Since the present invention has the above-mentioned configuration, the molten metal (metallurgy)
If the molten metal is poured from the spout, the molten metal will pass through the cavity and then the outflow passage to the outside, and after this state has passed for a predetermined time, the molten metal poured from the spout will flow from the downstream side to the upstream side of the cavity. It will fill up toward the gate.

In this case, since the piece is arranged in the molten metal flow path of the cavity, the piece comes into contact with the molten metal passing through the cavity.

Therefore, the piece is heated by new molten metal that is poured from the time when pouring is started from the spout to the time when the outflow passage is closed and reaches the piece, and then the piece is surrounded by the molten metal. become.

(Example) Hereinafter, the Example of this invention is described based on drawing.

In the drawings, FIG. 1 is a cross-sectional view of a mold apparatus to which the present invention is applied, FIG. 2 is a cross-sectional view of a piece installed in its cavity, and FIG. 3 is a main part showing a welding state of the piece and a casting. It is an expanded sectional view.

In FIG. 1, reference numeral 10 is a mold for molding a camshaft for a multi-cylinder engine. Inside the mold 10, a camshaft-forming cavity 11 extending vertically and a lower portion of the cavity 11 are provided outside. An outflow path 15 extending in the horizontal direction is formed to communicate with each other.

Further, in the mold 10, there is formed a preliminary chamber 16 which extends vertically in parallel with the cavity 11 and communicates with the lower end portion in the middle of the outflow passage 15.

The cavity 11 has a large diameter and a plurality of cam piece fitting portions 12, a gear piece fitting portion 13, and a journal portion 14 which are vertically spaced apart from each other by a predetermined distance, and the cam piece fitting portion 12 and the gear piece fitting portion 12 are formed. A cam piece 17 and a gear piece 18 are fitted and locked on the shaft 13.

As shown in FIG. 2, the cam piece 17 and the gear piece 18 are formed by forming a thin annular fixing piece 20 projecting in the axial direction on an inner peripheral wall 19a of an annular main body 19. The fixing piece 20 is formed on the inner peripheral wall of the piece main body (17, 18) having an outer diameter of about 60 mm and an inner diameter of about 40 mm with a thickness of about 0.2 to 1.5 mm and a width of about 5 mm in the axial direction.
In this case, the thickness of the fixing piece 20 may be formed in a taper shape that gradually becomes thinner toward the axis.

The mold 10 described above is a split mold that is vertically separable on the upper surfaces of the cam piece fitting portion 12, the gear piece fitting portion 13, and the journal portion 14, and the upper portion of the mold 11 is the upper portion of the mold 10. Forming a sprue 11a communicating with the.

The downstream end of the outflow passage 15 described above is opened and closed by a closing valve 21 attached to the side of the mold 10, and a molten metal receiver 22 is arranged at the downstream end of the outflow passage 15.

Reference numeral 23 is a control device for closing the closing valve 21, and corresponding to the wall thickness of the fixed piece 20 of the cam piece 17 and the gear piece 18, after the molten metal is poured from the sprue 11a, the closing valve 21 is closed after a predetermined time has elapsed. Then, the outflow passage 15 is closed.

According to the above-described embodiment, if molten metal (molten metal) is poured from the sprue 11a, the molten metal will first be stored in the cavity 11 and the outflow passage 15.
Will flow out to the molten metal receiver 21.

When this state elapses for a fixed time, the control device closes the closing valve 2.
1 is closed and the outflow passage 15 is closed, so that while flowing into the preliminary chamber 16, the cavity 11 is gradually filled from the lower side to the upper sprue 11a.

In this case, the fixed piece 20 of each cam piece 17 and gear piece 18 is provided in the axial center portion of the cavity 11a, that is, in the molten metal flow path.
Because of the protrusion, the fixing piece 20 comes into contact with the molten metal passing through the cavity 11.

Therefore, the pieces 17 and 18 and the fixing piece 20 are sufficiently immersed in the new molten metal poured from the sprue 11a for a long time, and as a result, as shown in FIG.
After the surface layer portion (a) of 0 is melted, it is surrounded by the new molten metal that has arrived at the fixing piece 20 portion.

It should be noted that the present invention is directed to the preliminary chamber 16 and the piece fixing piece 20.
May be reduced or omitted.

(Effects of the Invention) As is clear from the above description, the present invention allows the molten metal poured from the sprue to be circulated in the cavity for a predetermined time, and the flowing high temperature molten metal heats the piece placed in the cavity. As a result, the piece and the casting surrounding the piece can be welded smoothly, and the effect that the two can be firmly fixed together is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a mold apparatus to which the present invention is applied, FIG. 2 is a sectional view of a piece installed in the cavity, and FIG. 3 is an enlarged sectional view of an essential part showing a welding state of the piece with a casting. FIG. 4 is a cross-sectional view of a conventional mold device, FIG. 5 is a cross-sectional view of a piece installed in the cavity, and FIG.
The figure is a cross-sectional view showing a joined state of the piece and the casting. 10: Mold, 11: Cavity, 11a: Gate, 1
2: cam piece fitting portion, 13: gap piece fitting portion, 1
4: Journal section, 15: Outflow channel, 16: Reserve room, 1
7: cam piece, 18: gear piece, 19: main body, 19
a: inner peripheral wall, 20: fixing piece, 21: closing valve, 22: molten metal receiver, 23 control device, (ii): surface layer part.

Claims (3)

[Claims] 1. A cavity for communicating with a sprue in a mold,
After forming an outflow path for communicating the end of the cavity with the outside, installing a piece formed in a predetermined shape in the cavity in advance, and flowing out the molten metal poured from the spout from the outflow path to the outside by a predetermined amount. And a method of casting a cast-in-fill casting characterized in that the outflow passage is closed to fill the cavity with the molten metal. 2. The cast-in-girth casting method according to claim 1, wherein the piece has a plate-shaped fixing piece projectingly formed on a part of a peripheral wall of the piece toward the inside of the cavity. 3. The piece is annular and has a plate-shaped fixing piece extending in a circumferential direction on an inner peripheral wall of the piece so as to project inwardly. The cast-in-gurney casting method according to item 1.