JP2017200697A - Method of positioning core in casting mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of positioning a core in a casting mold, capable of substantially eliminating a cast hole when a water jacket core is positioned by using a baseboard.SOLUTION: A water jacket core 11 is disposed in a lower die 10L, and an oil housing core 12 is disposed on the water jacket core 11. Dies 10F, 10R are disposed on the outer peripheries of the cores 11, 12. When a cylinder head 18 is cast by injecting molten metal into the casting mold 10, a positioning baseboard 20 is formed on one side of the water jacket core 11 disposed in the lower die 10L. When the oil housing core 12 is disposed, the oil housing core 12 is disposed on the lower die 10L, sandwiching the positioning baseboard 20, so as to position the water jacket core 11.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a casting mold for casting a cylinder head or the like of an engine, and more particularly to a core positioning method in a casting mold for positioning a core in the casting mold.

  When casting a cylinder head of an engine, a core for forming a water jacket or an oil housing in the cylinder head is placed in a casting mold and cast.

  FIG. 4 shows a conventional method of casting a cylinder head.

  As shown in FIGS. 4A to 4D, the casting mold 50 includes a lower mold 50L, a front mold 50F, a rear mold 50R, and left and right molds (not shown). . In this casting mold 50, a water jacket core 51 forming a water jacket and an oil housing core 52 forming an oil housing are arranged, and the cores 51, 52 are positioned in the casting mold 50, and In this state, molten aluminum 53 is poured to cast a cylinder head.

  The water jacket core 51 is formed with baseboards 52f and 52r for positioning and as cast holes. Baseboard receiving portions 54f and 54r are formed on the front side and the rear side of the lower mold 50L.

  As shown in FIG. 4B, the water jacket core 51 is disposed on the lower die 50L, and the front and rear baseboards 52f and 52r thereof are the baseboard receiving portions 54f and 54r of the lower die 50L. And is sandwiched between baseboard pressing portions 55f and 55r of the front side mold 50F and the rear side mold 50R, and the water jacket core 51 and the oil are placed in the casting mold 50 as shown in FIG. The housing core 52 is positioned and fixed.

  In this state, as shown in FIG. 4 (d), molten aluminum 53 is poured into the casting mold 50, and after cooling, the cylinder head is taken out from the casting mold 50 together with the cores 51 and 52, and the center is removed. The cylinder head is cast by discharging the sand of the children 51 and 52 from the cast product.

  At this time, various holes are formed in the cast product, and the sand of the cores 51 and 52 is discharged through the holes, and the baseboards 52f and 52r serve as cast holes at that time.

JP 2000-312961 A JP 2011-177726 A JP 2012-035312 A JP 2011-190731 A

  However, since the cast hole formed by the baseboards 52f and 52r is connected to the water jacket, it is necessary to seal the cast hole after casting. For this reason, there is a problem that after the punched hole is drilled, post-processing is required to drive and seal the sealing cap.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a core positioning method in a casting mold that solves the above-mentioned problems and can substantially eliminate the need for a cast hole when positioning a water jacket core using a baseboard. There is.

  In order to achieve the above object, the present invention arranges a water jacket core in a lower mold, arranges an oil housing core on the water jacket core, installs a mold on the outer periphery of these cores, When casting a cylinder head by pouring molten metal into the casting mold, a positioning baseboard is formed on one side of the water jacket core disposed in the lower mold, and the oil housing core is disposed. A core positioning method in a casting mold is provided, wherein an oil housing core is positioned on the lower mold with the positioning baseboard interposed therebetween to position the water jacket core.

  The present invention exhibits an excellent effect that the positioning of the water jacket core can be performed and the cast hole can be eliminated by forming the positioning baseboard on one side of the water jacket core.

It is process drawing which shows one embodiment of this invention. It is an enlarged view of the location on the rear side of the casting mold of FIG. It is a principal part perspective view after casting in FIG. It is process drawing which shows conventional core positioning and casting.

  A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a process diagram showing core positioning and casting.

  First, as shown in FIG. 1A, casting is performed by setting the rear mold 10R on the rear side of the lower mold 10L, setting the water jacket core 11 and then setting the front mold on the front side of the lower mold 10L. The mold 10F is set, the oil housing core 12 is set as shown in FIG. 1 (c) as shown in FIG. 1 (b), and the molten aluminum 19 is placed in the casting mold 10 as shown in FIG. 1 (d). Is poured into a cast product.

  In this embodiment, as shown in FIGS. 1A to 1C, a positioning baseboard 20 is formed on the rear side of the water jacket core 11, and on the rear side of the oil housing core 12. A baseboard holding member 21 that contacts the lower mold 10L and sandwiches the positioning baseboard 20 with the lower mold 10L is formed to position the rear water jacket core 11.

  In this case, in order to position the water jacket core 11 accurately, the water jacket core 11 is formed with a baseboard 22 that is a punched hole similar to the conventional one, and is sandwiched between the lower mold 10L and the front mold 10F for positioning. However, the front side of the water jacket core 11 may also be formed of the positioning baseboard 20.

  FIG. 2 shows details of the rear side portion of the casting mold shown in FIG. 1 (d), and FIG. 3 is a perspective view of the rear side cylinder head 18 (cast product) as viewed from below.

  The positioning skirting board 20 is spaced from the core body 11a that forms the water jacket of the water jacket core 11 with respect to the cooling water flow path portion 20a that extends downward from the lower surface 18l of the cylinder head 18 and the rear mold 10R. It comprises a baseboard part 20c positioned below the baseboard pressing member 21 to be placed and a connecting part 20b for connecting the cooling water channel part 20a and the baseboard part 20c.

  The connecting portion 20b of the positioning base plate 20 is formed so that the upper surface thereof is the same height as the lower surface 18l of the cylinder head 18, and the base plate portion 20c is formed so as to be higher than the lower surface 18l of the cylinder head 18. Is done.

  The lower mold 10L is formed with a connecting portion receiving groove 10b for receiving the lower portion of the cooling water flow path portion 20a of the positioning baseboard 20 and the connecting portion 20b. Further, the lower mold 10L is formed with a baseboard receiving groove 10c that is continuous with the connecting part receiving concave groove 10b and receives the baseboard part 20c.

  The baseboard pressing member 21 is formed such that the lower surface thereof is in contact with the baseboard portion 20c and in contact with the lower mold 10L on the rear side. A positioning protrusion 10e that fits into the positioning groove 21e of the baseboard pressing member 21 is formed on the lower mold 10L that contacts the baseboard pressing member 21.

  The baseboard pressing member 21 is formed to have a size so as to form a gap with the rear mold 10R and to form a gap with the left and right side molds (not shown). A gear case portion 18 g of the cylinder head 18 is formed around the member 21.

  Next, the operation of the present embodiment will be described.

  The water jacket core 11 has a positioning skirting board 20 formed on the rear side, and the rear side of the water jacket core 11 has a baseboard part 20c of the positioning skirting board 20, a lower mold 10L, and an oil housing. The water jacket core 11 and the oil housing core 12 can be positioned by being sandwiched by the lower surface of the base plate pressing member 21 of the core 12 and part of the lower surface of the pressing member 21 contacting the lower mold 10L.

  Further, when the sanding of the positioning skirting board 20 is performed after casting, only a cooling water supply path is formed on the lower surface 18l of the cylinder head 18 by the cooling water flow path portion 20a of the positioning skirting board 20. is there. As a result, the cooling water passage is connected to the flow passage of the cylinder block, so that a conventional punched hole is not formed, and sealing is not required.

  Further, the positioning baseboard 20 of the water jacket core 11 is held by the lower surface of the baseboard pressing member 21, and a gear case portion 18g is formed around the baseboard pressing member 21, and the water of the gear case portion 18g is formed. Since no hole is formed on the surface on the jacket side, sealing is unnecessary.

  As described above, according to the present embodiment, the positioning base 20 is formed on the water jacket core 11 and is sandwiched between the lower mold 10L and the oil housing core 12, thereby eliminating the need for a cast hole. Can do.

10 Casting mold 10L Lower mold 10F, 10R Mold 11 Water jacket core 12 Oil housing core 20 Positioning baseboard

Claims (4)

  A water jacket core is placed on the lower mold, an oil housing core is placed on the water jacket core, a mold is placed on the outer periphery of these cores, and molten metal is poured into the casting mold. When casting the cylinder head, a positioning skirting board is formed on one side of the water jacket core disposed in the lower mold, and when the oil housing core is disposed, the positioning baseboard is sandwiched between the lower skirting boards. A core positioning method in a casting mold, wherein an oil housing core is disposed on a mold to position a water jacket core.   2. The casting mold according to claim 1, wherein the positioning baseboard is connected to a water jacket of the water jacket core and is formed to be positioned on a lower surface of a baseboard pressing member formed on the oil housing core. The core positioning method.   The positioning baseboard is disposed at a distance from a cooling water flow path portion extending downward from a lower surface of the cylinder head from a core body forming a water jacket of the water jacket core and a rear side mold. The core positioning method in a casting mold according to claim 1 or 2, further comprising a baseboard portion positioned below the core of the oil housing, and a connecting portion that connects the cooling water flow path portion and the baseboard portion.   The core positioning method in a casting mold according to claim 3, wherein a cooling water flow path formed by the cooling water flow path portion of the positioning baseboard is formed on the lower surface of the cylinder head after casting.

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