KR100578066B1 - Metallic mold structure for forming sand mold for water jacket of cylinder block - Google Patents

Abstract

The present invention relates to a mold structure for forming a water jacket of a cylinder block, which does not need to give a gradient to a partition wall. Lower mold 10 having a block 12 is provided; It is formed to have a right triangular shape and consists of several pairs arranged so that one side of the block 12 of the lower mold 10 is perpendicular to the space of the portion facing each other, along the rows to be arranged The insert member 40 which is installed to slide and has a concave groove 42 for forming a partition on a vertical side facing each other and which is elastically supported in a direction apart from each other by a pair of springs 32. ; An upper mold 20 having a plurality of blocks 22 arranged in a row in pairs having an outer circumferential surface having the same center point on opposite sides of the portions facing each other so as to correspond to the blocks 12 of the lower mold 10; And an insert member actuator 50 provided in the upper mold 20 by having a groove 52 having the same shape as that of the pair of insert members 40 in a vertical side contact state.

Cylinder, water jacket, death penalty, bulkhead, gradient

Description

Metal mold structure for forming sand mold for water jacket of cylinder block

1 is a schematic view showing a mold structure for forming a water jacket sand mold of a cylinder block according to the prior art;

Figure 2 is a view for explaining the problem of the conventional water jacket sand mold.

3 is a schematic configuration diagram showing a mold structure for water jacket sand forming of a cylinder block according to the present invention;

4 is a perspective view showing a lower mold which is a main part of the present invention;

5 is a perspective view showing an upper mold which is a main part of the present invention;

Figure 6 is a detailed view of the main portion showing the state before the mold of the present invention is molded;

7 is a detailed view showing the main part after the mold of the present invention is molded.

※ Explanation of symbols about main part of drawing ※

10: bottom 12: block

20: Pictograph 22: Block

32: spring 40: insert member

41B: arc portion 41A: flat portion

42 groove 50 insert member actuator

52: home

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold structure for water jacket sand forming of a cylinder block, and more particularly, to a mold structure for water jacket sand forming of a cylinder block, which does not need to give a gradient to a partition.

In general, a water jacket, which is a coolant passage for preventing engine overheating, is formed in a cylinder block of an engine, and a water jacket is formed by using sand to form a water jacket shape, and then installing the sand mold on a mold. The water jacket is formed in the cylinder block by the process of performing the casting operation.

The water jacket shaped sand mold 1 is formed through the upper die 3 and the side die 4 which behaves with the fixed lower mold 2, as schematically shown in FIG.

In addition, the sand mold 1 manufactured by using a conventional mold structure has a shape in which the thickness of the partition wall 5 becomes smaller from the center to the top and the bottom thereof, as shown in FIG.

However, when the upper and lower thicknesses of the partition wall 5 are small, the rigidity is lowered, and thus, when the cylinder block is manufactured by casting, cracks are generated in the partition wall when the molten metal is injected.

In addition, when the thickness thereof is increased in order to reduce the occurrence of cracks in the partition 5, the interval between the cylinder bores is widened, which adversely affects the rigidity and vibration, as well as the size of the cylinder block.

Accordingly, the present invention is to solve the above-mentioned problems, and to prevent the occurrence of cracks in the partition wall due to the injection of the molten metal during the manufacture of the cylinder block by making the thickness constant without giving a gradient to the sand wall partition for forming the water jacket It is an object of the present invention to provide a mold structure for forming a water jacket sand mold of a cylinder block.

As a technical configuration for achieving the above object, in the mold structure for forming a sand mold having a water jacket shape of a cylinder block, a pair having an outer circumferential surface of an arc shape having the same center point on opposite sides of the portions facing each other; A lower mold having a plurality of blocks arranged in a row; It is formed to have a shape of a right triangle formed of a plurality of pairs arranged so that one side of the lower block is perpendicular to the space of the area facing each other, installed so as to slide along the row in which the block is arranged, facing each other An insert member having a concave groove for forming a partition on a vertical side, the insert members being elastically supported in a direction away from each other by a pair of springs; An upper mold having a plurality of blocks arranged in a row in pairs having an outer circumferential surface having the same center point on opposite sides of the portions facing each other so as to correspond to the lower blocks; And an insert member actuator installed in the upper mold having a groove having the same shape as that of the paired insert members when the vertical sides are in contact with each other. By providing.

In addition, in the mold structure of the present invention, the surfaces facing each other of the insert members are flat portions having grooves for forming partitions, and both sides of the flat portions have the same curvature as the outer circumferential surface of the block. It is good that it is an arc part formed so that it may have an arc shape.

Further, in the mold structure of the present invention, the hypotenuse portion of the insert member is formed in a step shape, the groove of the insert member actuator is preferably formed in a step shape of the same shape as the step portion of the insert member.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is a schematic configuration diagram showing a mold structure for forming a water jacket sand mold of a cylinder block according to the present invention, Figures 4 and 5 are perspective views showing in detail the lower mold and the upper mold as the main part of the present invention, The mold has a top die 20 and a side die (not shown) that behave with a fixed bottom die 10. For convenience of description, the side die is not shown.

The lower mold 10 has a plurality of pairs of blocks 12. Each pair of blocks 12 is formed so that the portions facing each other have a planar shape and the opposite portions have an outer circumferential surface of the same circular arc shape.

Each of the pairs of blocks 12 forms a predetermined space between the portions where the blocks 12 face each other, and has a support shaft 30 fixedly installed to have a long length along the space.

In addition, a plurality of springs 32 are fitted to the support shaft 30, and insert members 40 are positioned on both sides of the springs 32, respectively. At this time, the spring 32 is located between the blocks 12 of each pair.

The insert member 40 is mounted to slide along the support shaft 30, and the insert member 40 is formed to have a right triangle shape in which the width thereof becomes narrower toward the top thereof, and is disposed so that one vertical side thereof faces each other. .

In addition, the insert member 40 has a concave groove 42 for forming a partition on an upper surface of the surface facing each other as shown in Figure 6 and the spring, the lower portion, that is, the portion where the support shaft 30 is inserted through A spring seating groove 44 is formed to receive the end of 32.

In addition, the surface of the part corresponding to the hypotenuse of the insert member 40 may have a step shape.

In particular, the surfaces of the insert members 40 facing each other are formed with a flat portion 41A having a planar shape, and portions of both sides of the flat portion 41A are formed with the block ( A circular arc portion 41B formed to have an arc shape having the same curvature as the outer circumferential surface of 12). At this time, the arc portion 41B forms the same surface as the outer circumferential surface of the block 12 when the neighboring planar portions 41A are in a shaping state in contact with each other.

The upper mold 20 has a plurality of pairs of blocks 22 corresponding to the lower mold 10, wherein each pair of blocks 22 face each other like the blocks 22 of the lower mold 10 Is a planar shape and the opposite portion is formed to have an outer circumferential surface of the same arc shape as the center point.

Each of the pairs of blocks 22 forms a predetermined space between the portions in which the blocks 22 face each other, and a groove into which the insert member 40 of the lower mold 10 is inserted. An insert member actuator 50 having 52) is provided.

The groove 52 of the insert member actuator 50 has the same shape as the hypotenuse of the insert member 40 when the planar portions 41A of the insert member 40 are in contact with each other.

In addition, a sand injection nozzle 60 for injecting sand is installed on the upper mold 20.

The operation of the present invention having the above configuration will be described.

6 is a detailed view of the main portion showing the state before the mold of the present invention is molded, and shows that the insert member 40 of the lower mold is kept at a predetermined distance from each other by the spring 32.

That is, no external force is applied to the insert member 40, and in this state, the surfaces of the insert members 40 facing each other are separated by a predetermined distance by the elastic force of the spring 32.

In this state, when the upper mold is moved downward, the insert member actuator 50 mounted on the upper mold is lowered together, and when the insert member actuator 50 is lowered, the groove formed in the insert member actuator 50 ( 52, the lower insert member 40 begins to be inserted.

When the lower insert member 40 is inserted into the groove 52 of the insert member actuator 50, the hypotenuse portion of the insert member 40 contacts the groove 52 to bring the insert members 40 closer to each other. The spring 32 is retracted.

When the upper mold and the lower mold are combined as shown in FIG. 7, the surfaces facing each other of the insert member 40 are in close contact with each other, and a space for forming a partition wall is provided by the groove 42.

In this state, sand is injected through the sand injection nozzle 60, and after a predetermined time, that is, after a firing cycle time in which sufficient firing can be made, the upper mold is raised.

When the upper die is raised in this way, the insert member 40 inserted into the groove 52 is freed, so that the insert members 40 are separated from each other as shown in FIG. 6 by the elastic restoring force of the spring 32. Is moved.

Therefore, the production of the sand mold for forming the water jacket is completed, and the sand mold has a partition formed by the groove 42 of the insert member 40.

At this time, the thickness of the partition is completed, the overall partition is constant, which makes it possible to prevent the occurrence of cracks in the partition wall by the injection of the molten metal when manufacturing the cylinder block.

In addition, according to such a mold structure of the present invention, the production of a sand mold having a hole in the partition wall is also easy.

As described above, according to the mold structure for forming a water jacket of a cylinder block according to the present invention, the partition wall of the sand mold can be manufactured to have a constant thickness, thereby preventing cracking of the partition wall due to the injection of molten metal when the cylinder block is manufactured. Has an excellent effect.

In addition, by preventing the occurrence of cracks in the partition wall to lower the defective rate of the cylinder block to improve the productivity as well as to reduce the manufacturing cost of the engine has an excellent effect.

Claims (3)

In the mold structure which forms the sand mold which has the water jacket shape of a cylinder block, A lower mold 10 having a plurality of blocks 12 arranged in a row, formed in pairs having an outer circumferential surface having the same center point on opposite sides of a portion facing each other; It is formed to have a shape of a right triangle is formed of a plurality of pairs arranged so that one side of the block 12 of the lower mold 10 is perpendicular to the space of the area facing each other, along the row in which the block 12 is disposed The insert member 40 which is installed to slide and has a concave groove 42 for forming a partition on a vertical side facing each other and which is elastically supported in a direction apart from each other by a pair of springs 32. ; An upper mold 20 having a plurality of blocks 22 arranged in a row in pairs having an outer circumferential surface having the same center point on opposite sides of the portions facing each other so as to correspond to the blocks 12 of the lower mold 10; And The pair of insert members 40 includes an insert member actuator 50 installed in the upper mold 20 having a groove 52 having the same shape as that of the vertical side in contact with the insert member 40. The mold structure for water jacket sand molding of the cylinder block to be made. The surface of the insert member (40) facing each other is a portion in which the grooves (42) for forming the partitions are formed. The flat portion (41A) has a planar shape, and both side portions of the flat portion (41A). The mold structure for forming a water jacket of a cylinder block, characterized in that the arc portion (41B) formed to have an arc shape having the same curvature as the outer peripheral surface of the block (12). The method of claim 1, wherein the hypotenuse portion of the insert member 40 is formed in a step shape, the groove 52 of the insert member actuator 50 is a step shape of the same shape as the step portion of the insert member 40. Mold structure for forming a water jacket sand mold of the cylinder block, characterized in that formed by.

Images