JPH0655257A - Sand shake out method of cylinder block - Google Patents

Abstract

PURPOSE:To provide a sand shake out method so as to satisfactorily remove the sand core remained inside cylinder block, which is produced by high pressure casting. CONSTITUTION:When sand shake out is executed after casting for a cylinder block 1, in which a water jacket 3 as well as a bridge 6 between a cylinder head mounting surface 5 and sand core 4 are formed, shot blasting is executed by injecting shots from a slant direction for the neighborhood of one side part 6a of the bridge 6 to one side part 4a of the sand core 4, and then, shot blasting is executed by injecting shots from a slant direction for the neighborhood of the other side part 6b of the bridge 6 to the other side part 6b of the bridge 6 to the other side part 4b of the sand core 4. Thus, sand shake out from the cylinder block 1 is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for manufacturing a cylinder block having a water jacket, and in particular, it is provided with a bridge connecting the outer wall portion and the inner wall portion of the water jacket on the cylinder head surface to improve the bore rigidity. The present invention relates to a method for sanding a cylinder block, which is suitable for removing a sand core after high-pressure casting in a cylinder block that is high-pressure cast using a sand core for strengthening.

[0002]

2. Description of the Related Art Conventionally, many cast iron cylinder blocks have been adopted for automobile engines, and such cast iron cylinder blocks have been manufactured by using a casting sand molding mold. According to this, many aluminum cylinder blocks have been adopted,
Such an aluminum cylinder block was manufactured by a low pressure casting method.

On the other hand, casting by die casting has come to be adopted as a high-pressure casting method which is more excellent in productivity than the low-pressure casting method and is capable of densifying the structure.

Even in such a cylinder block made of aluminum, it is necessary to form a water jacket for a water-cooled structure. However, when forming the water jacket, the water jacket metal is used so as to withstand a high casting pressure. Since a mold is used, the water jacket is formed with the entire surface open on the cylinder head mounting surface so that the water jacket mold can be satisfactorily demolded after casting. It was.

However, when the water jacket is formed so as to open over the entire surface of the cylinder head mounting surface, the bore rigidity is low, so that the outer wall portion and the inner wall portion of the water jacket (that is, the outer wall of the cylinder). It is preferable to use a closed deck type in which a bridge) is connected to the (part) and a sand core has to be used in the part where the bridge is formed (see JP-A-1-150456).

[0006]

As described above, it is necessary to use a sand core to form a closed deck type in which the outer wall portion and the inner wall portion of the water jacket are connected by a bridge. When a cylinder block is manufactured by die-casting, a strong sand core that withstands high casting pressure is used, and since the cooling time is short, the time in the high temperature state is short. Due to the fact that the sand core collapses less, it becomes more difficult to remove the sand core, and vibration due to the knockout machine that was used when performing sand removal after manufacturing the cylinder block by the conventional low pressure casting method. However, there is a problem that sand removal cannot be performed to a certain degree, and a cylinder block is formed using a sand core by such a high pressure casting method. It has been a problem that allows the sand out of the case of producing a click good.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art. Even when a cylinder block is manufactured by using a sand core by a high pressure casting method, sand removal from the cylinder block is excellent. The purpose is to be able to do.

[0008]

According to the method for sanding a cylinder block according to the present invention, a water jacket die is dividedly arranged in the vicinity of a bore core installed corresponding to the number of cylinders, and the water jacket die is placed between the water jacket die. In addition, casting is performed using a mold in which a sand core is installed at a position inside the cylinder head with a space from the mounting surface, and a water jacket is formed by the water jacket mold and the sand core. When performing sand removal after casting in a cylinder block in which a bridge is formed in the space between the cylinder head mounting surface and the sand core, a diagonal direction from the vicinity of one side portion of the bridge to one side portion of the sand core After removing the one side part of the sand core from the diagonal direction by performing shot blasting to inject a shot from It is configured to perform shot blasting to inject a shot from the diagonal direction to the other side portion of the sand core to remove the other side portion of the sand core from the diagonal direction, and to perform sand removal from the cylinder block. It has a feature.

In an embodiment adopted as necessary, when flash is generated at the boundary position between the water jacket mold and the sand core in the cylinder block, the flash is made by a cutting tool such as an end mill. It is also possible to remove sand by sandblasting after shot blasting.

[0010]

In the cylinder block sand removing method according to the present invention, the bridge is formed in the cylinder block in which the cylinder head mounting surface and the inner wall portion and the outer wall portion of the water jacket are connected by a bridge to increase the bore rigidity. Even if the sand core remains in the bridge formation part by using the sand core in order to shoot from an oblique direction to the one side part of the sand core from the vicinity of the one side part of the bridge. After performing a shot blast to eject one side portion of the sand core from an oblique direction, shot blast to inject a shot from the diagonal direction to the other side portion of the sand core from the vicinity of the other side portion of the bridge The other side of the sand core is removed diagonally, so that the sand can be removed properly from the inside of the cylinder block. It is the thing.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cylinder block sand removing method according to the present invention will be described with reference to FIGS.

In the cylinder block according to the present invention, the water jacket molds are divided and arranged in proximity to the bore cores installed corresponding to the number of cylinders, and a space is provided between the water jacket molds and from the cylinder head mounting surface. As shown in FIG. 1, a plurality of bores 2 are formed in the cylinder block 1 after casting, because it is cast by die casting using a mold in which a sand core is installed at a position inside In addition, a water jacket 3 is formed in the vicinity of the bore 2 by a water jacket mold, and a sand core 4 remains inside and the sand core 4
The space provided between the cylinder head mounting surface 5 and the cylinder head mounting surface 5 is also cast to form the bridge 6.

Therefore, the sand core 4 is left in the cylinder block 1 having the sand core 4 left therein, and the sand core 4 is removed.
By removing the above, a water jacket continuous with the water jacket 3 is formed, but a flash beam 8 as shown in FIG. 2 is formed at the boundary between the water jacket mold and the sand core 4. At times, as shown in FIGS. 1 and 2, it is desirable to insert, for example, an end mill 9 as a cutting tool into the water jacket 3 and remove the flash 8 together with a part of the sand core 4 by the end mill 9. .

Subsequently, the cylinder block 1 from which the flash 8 has been removed is transferred to the product conveyor 11 shown in FIG.
The product is moved from the product inlet 12 to the primary shot blast chamber 13.

In the primary shot blast chamber 13, a plurality of blast nozzles 14 are supported by a blast nozzle support 15 in the same direction (downward leftward direction in the illustrated example). The body 15 is connected to a blast nozzle vertical drive mechanism 16, and the blast nozzle 14 is driven in parallel in the vertical direction.

Then, this primary shot blast chamber 1
3, in the vicinity of the one side portion 6a of each bridge 6 of the cylinder block 1, as shown in FIGS.
4 and 5, the blast nozzle 1 is slanted with respect to one side portion 4a of each sand core 4 in a direction indicated by a ⇒ mark D ₁ direction.
By performing shot blasting by injecting shots from _No. 4, the blast nozzle vertical drive mechanism 16 translates the blast nozzle 14 in the vertical direction (direction of arrow A ₁ ) to move the one side portion 4 a of the sand core 4 from an oblique direction. Remove.

The core sand and the shots that have been sanded out here are collected by the hopper 17.

Next, the cylinder block 1 is divided into partitions 22.
To the secondary shot blast chamber 23.

In the secondary shot blast chamber 23, a plurality of blast nozzles 24 are supported by a blast nozzle support 25 in the same direction (downward rightward direction in the illustrated example). The body 25 is connected to a blast nozzle vertical drive mechanism (not shown), and the blast nozzle 24 is driven in parallel in the vertical direction.

The second shot blast chamber 2
3, in the vicinity of the other side portion 6b of each bridge 6 of the cylinder block 1, as shown in FIGS.
Figures 4 and in the direction indicated by → mark D ₂ direction 5, the blast nozzle 2 in a direction oblique to the other side portion 4b of the sand core 4
4 performs shot blasting to inject shots, and moves the blast nozzle 24 in the vertical direction (direction of arrow A ₂ ) in parallel by a blast nozzle vertical drive mechanism (not shown), so that the other side portion 4 b of the sand core 4 is slanted. Remove from direction.

In addition, the above-mentioned diagonal directions (D ₁ , D
Strong shot blasting from _two directions) causes a strong rebound of the shot, so that the sand core 4 immediately below the bridge 6 can be removed well.

Subsequently, the cylinder block 1 is divided into partitions 3
From 2 to the product reversal / air blow chamber 33.

In the product inversion / air blow chamber 33,
The cylinder block 1 is supported by a product reversing support 34 and reversed, and a large number of air blow nozzles 35 are provided.
Is provided, while reversing the cylinder block 1,
By performing air blow from the air blow nozzle 35, unnecessary matters such as core sand and shot remaining in the water jacket 3 of the cylinder block 1 are removed and dropped into the hopper 38, and the cylinder block 1 that has finished sand removal is the outlet. It is taken out from 36.

[0024]

In the cylinder block sand removing method according to the present invention, the bridge is formed in the cylinder block in which the cylinder head mounting surface and the inner wall portion and the outer wall portion of the water jacket are connected by a bridge to increase the bore rigidity. Even if the sand core remains in the bridge formation part by using the sand core in order to shoot from an oblique direction to the one side part of the sand core from the vicinity of the one side part of the bridge. After performing a shot blast to eject one side portion of the sand core from an oblique direction, shot blast to inject a shot from the diagonal direction to the other side portion of the sand core from the vicinity of the other side portion of the bridge The other side of the sand core is removed diagonally, so that the sand can be removed properly from the inside of the cylinder block. Significantly excellent effect that a be is provided.

[Brief description of drawings]

FIG. 1 is an explanatory view of a partial slope of a cylinder block applied in a sanding method for a cylinder block according to an embodiment of the present invention.

2 is a cross-sectional explanatory view of a cylinder block taken along line II-II in FIG.

FIG. 3 is an explanatory diagram of shot blast equipment used in an example of the present invention.

FIG. 4 is an explanatory plan view of a cylinder block.

5 is a cross-sectional explanatory view taken along the line VV of FIG. 4, showing how the sand core remaining in the cylinder block is shot-blasted from an oblique direction.

[Explanation of symbols]

 1 Cylinder Block 2 Bore 3 Water Jacket 4 Sand Core 4a One Side of Sand Core 4b Other Side of Sand Core 5 Cylinder Head Mounting Surface 6 Bridge 6a One Side of Bridge 6b Other Side of Bridge 13,23 Shot Blast Chamber 14, 24 Blast nozzle

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takuya Arakawa 503 Kitahama, Oguchi Town, Matsusaka City, Mie Prefecture Aichi Machine Industry Co., Ltd.

Claims (2)

[Claims] 1. A position in which water jacket dies are dividedly arranged in the vicinity of bore cores installed corresponding to the number of cylinders, and a space between the water jacket dies and a space from a cylinder head mounting surface enters inside. Casting is performed by using a mold having a sand core installed therein, and a water jacket is formed by the water jacket mold and the sand core portion, and a bridge is formed in the space between the cylinder head mounting surface and the sand core. When performing sand removal after casting in a cylinder block having formed, one side portion of the sand core by performing shot blasting by injecting a shot obliquely from one side portion of the bridge to one side portion of the sand core from the vicinity of the one side portion of the bridge Is removed from an oblique direction, and then a shot is injected from an oblique direction to the other side portion of the sand core from the vicinity of the other side portion of the bridge. A method for sand removal of a cylinder block, which comprises performing a sandblast to remove the other side of the sand core from an oblique direction and sand removing from the cylinder block. 2. When flash is generated at a boundary position between the water jacket mold and the sand core in the cylinder block, after removing the flash by a cutting tool,
The sand removing method for a cylinder block according to claim 1, wherein the sand removing is performed by shot blasting.