JP2008229638A - Casting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a casting method capable of preventing the defects of castings and the damage of pouring pins by reducing the sliding resistance between the castings and the pouring pins when inserting and removing the castings into and from the pouring pins. <P>SOLUTION: Each of the pouring pins 1 is vibrated in the stage of inserting and removing the castings after the solidification of a molten metal and therefore, when the pouring pins are inserted and removed into the castings, the detachment effect of the castings and the pouring pins 1 can be promoted by sliding of the pouring pins 1. The sliding resistance of the castings and the pouring pins 1 is reduced, the damage of the surface treatment layers of the pouring pins 1 is suppressed and the faults, such as defects of the castings are prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a casting method in which a cast pin is disposed in a mold cavity and cast.

Conventionally, when the cast product is taken out from the mold after the molten metal is solidified, there has been a problem that a part of the cast product sticks to the core pin and a part of the cast product is lost. As a result, the defect rate of the cast product is increased, and furthermore, the casting mold facility needs to be stopped in order to peel off a part of the cast product stuck to the core pin, which significantly reduces the operation rate of the facility. I was letting.
That is, when the cast is taken out from the mold after the molten metal has solidified, the mold is opened, and if the cast is to be removed from the cast pin with a knock pin or the like, the casting resistance is caused by the sliding resistance between the cast and the cast pin. The surface treatment layer of the punch pin, for example, the surface treatment layer such as tuftlite, various PVC / CVC treatments, is damaged. When damage to the surface treatment layer of the casting pin is repeated, a phenomenon in which a part of the surface treatment layer peels occurs.
Furthermore, when the casting process is repeated in this state, a thermochemical reaction occurs between the molten metal in the cavity and the part where the cast pin is peeled off, and an intermetallic compound (baking) is generated at that site. The Then, when this cast product is taken out from the mold, a defective product in which a part of the cast product is chipped (galling) is formed, and in addition, in order to peel the baking generated on the surface of the core pin, a casting mold facility is used. It is necessary to stop the operation, which reduces the operating rate of the equipment and lowers the production efficiency.

Therefore, in Patent Document 1 as a conventional casting method, when the molten metal in the mold is solidified, the vibration frequency is set low by virtue of the synergistic effect of cooling and vibration by vibrating the casting pin while cooling. Also, a casting method is disclosed in which the effect of refinement of the metal structure is increased.
JP 2000-42707 A

  In the casting method disclosed in Patent Document 1 described above, in order to refine the metal structure, the cast pin is merely vibrated when the molten metal is solidified, and the sliding resistance between the cast product and the cast pin is determined. It is not intended to vibrate the core pin in order to reduce this.

  The present invention has been made in view of the above points, and when removing a cast product from a cast pin, the sliding resistance between the cast product and the cast pin is reduced, so that the cast product is defective or the cast pin is damaged. It is an object of the present invention to provide a casting method capable of preventing the above.

In order to solve the above problems, the casting method of the present invention is characterized in that the casting pin is vibrated at the stage of removing the cast product after solidification of the molten metal from the casting pin.
As a result, when the cast product is removed from the cast pin, the detachment action between the cast product and the cast pin can be promoted by the vibration of the cast pin, and the sliding resistance between the cast product and the cast pin is reduced. Further, the surface treatment layer of the casting pin is not damaged, and as a result, the defect of the cast product is suppressed and the defect rate can be reduced. In addition, since the baking to the core pin is suppressed, the operating rate of the equipment can be improved.
Various aspects of the casting method of the present invention and their actions will be described in detail in the following section (Aspect of the Invention).

(Aspect of the Invention)
In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified and described. In addition, each aspect is divided into a term like a claim, it attaches | subjects a number to each term, and is described in the format which quotes another term as needed. This is for the purpose of facilitating the understanding of the claimable invention, and is not intended to limit the combinations of the constituent elements constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description, embodiments, etc. accompanying each section, and as long as the interpretation is followed, there may be embodiments in which other constituent elements are added to the aspects of each section. In addition, an aspect in which the constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention. In each of the following items, each of (1) to (3) corresponds to each of claims 1 to 3.

(1) A casting method in which a cast pin is disposed in a cavity of a mold and is cast, wherein the cast pin is vibrated at a stage of removing the cast product from the cast pin after solidification of the molten metal. Casting method.
Therefore, in the casting method of the item (1), when the cast product is removed from the cast pin, the detachment action between the cast product and the cast pin can be promoted by the vibration of the cast pin. The sliding resistance with the pin is reduced, and damage to the surface treatment layer of the core pin is suppressed, and defects such as chipping of the cast product are prevented.

(2) A casting method in which a cast pin is placed in a mold cavity and cast, and the molten metal solidifies from the stage where pouring is started into the cavity and the cast product is removed from the cast pin. A casting method comprising vibrating the casting pin until a stage.
Therefore, in the casting method of the item (2), since the initial sticking of the molten metal to the core pin is prevented, the sliding resistance when the cast product is removed from the core pin is further reduced.

(3) The casting method according to (1) or (2), wherein vibrations propagating in an axial direction are applied to the core pin.
Therefore, in the casting method of the item (3), the structure for applying vibration to the casting pin is simplified.

(4) The casting pin is given to the casting pin in a stage in which pouring is started into the cavity, a stage in which the molten metal is solidified after the pouring is completed, and a stage in which the cast product is removed from the casting pin after the molten metal has solidified. The casting method according to the item (2) or (3), wherein the vibration form is changed.
Therefore, in the casting method of (4), in order to prevent the molten metal from sticking to the casting pin at the stage where the molten metal is started into the cavity, and in the stage where the molten metal is solidified after the completion of the molten metal, Further, in order to make the structure finer, at the stage where the cast product is pulled out from the casting pin after the molten metal has solidified, the vibration form (for example, at each stage so that the cast product can be easily pulled out from the casting pin (for example, Vibrations having different vibration modes, amplitudes, and frequencies) are applied to the casting pins.

  According to the present invention, it is possible to provide a casting method capable of reducing the sliding resistance between a cast product and a cast pin when the cast product is removed from the cast pin, thereby preventing the cast product from being defective or the cast pin being damaged. Can do.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to FIGS.
As shown in FIG. 1 and FIG. 2, a plurality of core pins 1 used in the casting method according to the embodiment of the present invention are fixed to a predetermined portion of a fixed mold 3 (the right mold in FIG. 2) 3. The vibration of a predetermined vibration form is applied. Each casting pin 1 has a shaft portion 6 protruding into the cavity 5 of the mold 4, and a disk-shaped head that is connected to the shaft portion 6 and disposed in a recess 10 provided in the fixed mold 3 of the mold 4. Part 7.

  The mold 4 is composed of a movable mold 2 and a fixed mold 3, and when the mold is clamped, a cavity 5 in the shape of a cast product is formed therein. A plunger sleeve 11 is disposed below the fixed mold 3, and a molten metal supply port (not shown) is formed in a part of the peripheral wall of the plunger sleeve 11. In the plunger sleeve 11, a plunger rod 13 having a plunger tip 12 fixed to the tip is slidably disposed. Further, a plurality of insertion holes 10a for inserting the casting pins 1 are formed at predetermined positions of the fixed mold 3, and concave portions 10 for disposing the heads 7 of the casting pins 1 are formed in these insertion holes 10a. . Then, by inserting the shaft portion 6 of the casting pin 1 into these insertion holes 10a and inserting the head portion 7 of the casting pin 1 into the recess 10, each casting pin 1 is fixed to the fixed mold 3, and each casting is performed. Each shaft portion 6 of the pin 1 protrudes into the cavity 5.

  Each core pin 1 is provided with a disk-like insulator 15 having the same diameter as the head 7 on the surface of the head 7 opposite to the shaft 6 side. The insulator 15 is made of cefine ceramic or the like. A piezoelectric film 16 formed in a rectangular shape smaller than the outer diameter of the surface of the insulator 15 is disposed. The piezoelectric film 16 is made of, for example, a single crystal film of a piezoelectric material having a high Curie point and a relatively high electromechanical coupling constant, lithium niobate, lithium tantalate, or a langasite single crystal. An electrode 17 for applying a voltage is disposed substantially at the center of the surface of the piezoelectric film 16. An oscillator 18 that supplies a predetermined voltage is electrically connected to the electrode 17, and the oscillator 18 imparts vibration in an optimal vibration form to the casting pin 1. The oscillator 18 is configured such that the amplitude and frequency of vibration applied to the casting pin 1 can be changed by changing the voltage or the like.

Next, the casting method according to the embodiment of the present invention will be described.
First, after the mold clamping, the casting pins 1 are vibrated in a predetermined vibration form before the pouring of the molten metal into the cavity 5 of the mold 4 is started.
That is, a predetermined voltage is applied from the oscillator 18 to the electrode 17 provided on the head 7 of the casting pin 1. Then, polarization occurs in the piezoelectric film 16, and the piezoelectric film 16 vibrates in the axial direction of the casting pin 1 due to the electrostrictive effect due to the polarization. The vibration of the piezoelectric film 16 is propagated through the insulator 15 to the shaft portion 6 of the casting pin 1 so that the shaft portion 6 vibrates in a predetermined vibration form. In the present embodiment, the vibration applied to the casting pin 1 is such that the applied voltage is set to a predetermined value of 10 to 500 V, the vibration mode is a longitudinal wave, and the frequency is about 10 to 100 KHz.
Next, the casting process is started in a state where the vibration of a predetermined vibration form is applied to the shaft portion 6 of each casting pin 1. First, as an initial stage of the casting process, molten metal is supplied from a molten metal supply port provided in the plunger sleeve 11 and is injected into the cavity 5 of the mold 4 from the plunger sleeve 11 by driving the plunger rod 13. Subsequently, as a middle stage of the casting process, the molten metal is solidified after the pouring of the cavity 5 is completed, and a cast product is cast. Finally, as a later stage of the casting process, when the movable mold 2 is opened and the cast product is pushed to the movable mold 2 side by a plurality of knock pins (not shown) slidably disposed in the fixed mold 3, the cast product is Is removed from each casting pin 1 and taken out from the fixed mold 3, and the casting process is completed.
Finally, after the cast product is taken out from the fixed mold 3, the application of vibration to each core pin 1 is stopped.

  By comprising in this way, the initial sticking of the molten metal to the surface of each casting pin 1 is prevented, and when the casting product is removed from each casting pin 1, the casting product and each casting pin 1. As a result, the sliding resistance between the cast product and each core pin 1 is greatly reduced.

In the embodiment of the present invention, the movable mold 2 is opened through the intermediate stage in which the molten metal in the cavity 5 is solidified from the initial stage in which pouring into the cavity 5 is started, and the cast product is each casting pin 1. Each casting pin 1 is vibrated in a predetermined vibration form throughout the entire casting process until it is removed from the fixed mold 3 and taken out from the stationary mold 3, and each casting pin 1 is cast after solidification of the molten metal. You may employ | adopt the form which vibrates only in the latter stage of the casting process which pulls out goods from each casting pin 1. FIG. Accordingly, when the cast product is removed from each casting pin 1, the detachment action between the cast product and each casting pin 1 can be promoted by the vibration of each casting pin 1, and the casting product and each casting pin 1. It is possible to reduce the sliding resistance.
Further, in the embodiment of the present invention, longitudinal wave vibration is applied to each casting pin 1, but transverse wave vibration may be applied, and the vibration mode is selected by selecting vibration to each casting pin 1. What can simplify the structure for providing is selected suitably.

Furthermore, in the embodiment of the present invention, each casting pin 1 is given the vibration of the same vibration form throughout the initial stage, the middle stage and the latter stage of the casting process. In addition, vibrations having an optimal vibration form may be applied in each of the initial stage, the middle stage, and the late stage of the casting process.
That is, the vibration mode (for example, vibration mode, amplitude, frequency) applied to each casting pin 1 is the most effective in preventing the initial sticking of the molten metal to each casting pin 1 surface in the initial stage of the casting process. In the middle of the casting process, or in the middle stage of the casting process, the vibrating form can make the metal structure of the molten metal finer, and in the latter stage of the casting process, the cast product can be easily removed from each casting pin 1. You may change and set to each vibration form.

As described above, according to the embodiment of the present invention, each casting pin 1 disposed so as to protrude into the cavity 5 of the mold 4 has all the stages from the initial stage through the middle stage to the later stage. Since the vibration of a predetermined vibration form is applied over the time, the initial sticking of the molten metal to the surface of each casting pin 1 is prevented, and further, when the cast product is removed from each casting pin 1 Since the detachment action between the cast product and each core pin 1 is promoted, the sliding resistance between the cast product and each core pin 1 is greatly reduced.
As a result, damage to the surface treatment layer of each casting pin 1 is suppressed, and the operating rate of the casting mold equipment can be dramatically improved. In addition, defects in the cast product are also suppressed, so the defect rate is reduced. Can be reduced.

FIG. 1 shows a casting pin used in a casting method according to an embodiment of the present invention, where (a) is a side view and (b) is a view seen from the head side. FIG. 2 is a view showing a state in which molten metal is poured into a mold cavity in the casting method according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Casting pin, 2 Movable type, 3 Fixed type, 4 Mold, 5 Cavity, 6 Shaft part, 7 Head part, 15 Insulator, 16 Piezoelectric film, 17 Electrode, 18 Oscillator

Claims (3)

A casting method in which a core pin is placed in a mold cavity and cast,
A casting method, wherein the casting pin is vibrated at a stage of removing the casting from the casting pin after solidification of the molten metal. A casting method in which a core pin is placed in a mold cavity and cast,
A casting method characterized in that the casting pin is vibrated from a stage where pouring into the cavity is started to a stage where the molten metal solidifies and the cast product is removed from the casting pin. The casting method according to claim 1, wherein a vibration propagating in an axial direction is applied to the core pin.

Images