JP7326869B2 - mold structure - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold structure, and more particularly to a mold structure having a core provided with baseboards at both ends in the longitudinal direction.

Conventionally, the cylinder head of an engine is provided with passages such as an intake/exhaust port as an intake/exhaust passage communicating with a combustion chamber, a water jacket as an engine cooling water passage, and an oil jacket as an engine oil space. . Therefore, when manufacturing such a cylinder head, casting is performed by assembling cores corresponding to these passages into a mold.
When such a long core is assembled in a mold, generally, baseboards are provided at both ends of the core, and the core is positioned and supported with respect to the mold via these baseboards.

The mold structure of the cylinder head of Patent Document 1 includes a mold consisting of an upper mold, a lower mold, and a plurality of side molds constituting side walls, and a plurality of cores including a water jacket core assembled to the lower mold, First and second baseboards formed at both ends in the longitudinal direction of the water jacket core are provided with first and second engaging portions recessed, respectively, and the first engaging portion is formed on the lower die. The second engaging portion is configured to be engaged with the engaged portion formed on the lower die so as to be movable only in the longitudinal direction.

Japanese Patent No. 3752887

In the mold structure of the cylinder head of Patent Document 1, the second engaging portion of the water jacket core is formed so as to be movable in the longitudinal direction with respect to the engaged portion formed on the lower mold. The presence of molten metal around the mold, which has a small amount of thermal expansion, and the water jacket core, makes it possible to absorb the difference in the amount of thermal expansion between the mold and the water jacket core, which have a large amount of thermal expansion. It is possible to avoid troubles such as breakage of the water jacket core due to the difference in the amount of expansion.
However, with the technique disclosed in Patent Document 1, there is a possibility that the dimensional accuracy of the casting, which is a product, cannot be ensured.

In the technique of Patent Document 1, the first engaging portion of the water jacket core is immovably engaged with the engaged portion formed on the lower die, while the second engaging portion of the water jacket core is Since it is formed so as to be movable in the longitudinal direction with respect to the engaged portion formed on the lower mold, the difference in the amount of thermal expansion between the mold and the elongated water jacket core causes the water jacket core to expand. It will be locally concentrated on the second engaging portion and the portion corresponding to the second engaging portion of the mold.
That is, there is a structural (dimensional) error in the casting structure due to the locally concentrated relative positional deviation between the second engaging portion of the water jacket core and the portion corresponding to the second engaging portion of the mold. , and the dimensional accuracy of the final casting cannot be ensured.

SUMMARY OF THE INVENTION An object of the present invention is to provide a casting mold structure and the like that can ensure the dimensional accuracy of a casting even when casting using a long core.

A mold structure according to claim 1, comprising a mold for casting a casting, and a core disposed in the mold for forming a passageway extending in the longitudinal direction of the casting, wherein the core First and second end baseboards and an intermediate baseboard supported by the mold are respectively provided at both longitudinal ends and a longitudinal intermediate part of the The intermediate baseboard is supported by the mold so as to be movable in all directions, and the intermediate baseboard is restrained from moving in the longitudinal direction, the lateral direction orthogonal to the longitudinal direction of the casting, and the vertical direction via the engaging portion. It is characterized by being supported by a mold.

In this mold structure, first and second end baseboards and intermediate baseboards supported by the mold are provided at both longitudinal end portions and longitudinal intermediate portion of the core, respectively. Since the end baseboards are supported by the mold so as to be movable in the longitudinal direction, the supportability of the long core to the mold is increased, and the difference in the amount of thermal expansion between the mold and the core in the longitudinal direction is reduced. It is possible to avoid problems such as breakage of the core caused by
Since the intermediate baseboard is supported by the mold through engaging portions that restrict movement in the longitudinal direction, the transverse direction orthogonal to the longitudinal direction of the casting, and the vertical direction, the mold and the core are supported. It is possible to disperse the difference in the amount of thermal expansion generated between the mold and the core to both end portions of the core, respectively, suppressing the displacement of the relative positional relationship between the mold and the core over the entire longitudinal direction. can do.

The invention of claim 2 is the invention of claim 1, wherein the engaging portion has a wedge-shaped cross section orthogonal to the longitudinal direction and the transverse direction, and the mold engages the engaging portion. It is characterized by having a concave portion that
According to this configuration, it is possible to constrain the movement of the core in the longitudinal direction and the lateral direction with reference to the intermediate portion of the core with a simple configuration.

According to the invention of claim 3, in the invention of claim 1 or 2, the first and second end baseboards are restrained from moving in the lateral direction, and move in the lateral direction when viewed from the longitudinal direction. It is characterized by being arranged so as to be offset.
According to this configuration, it is possible to ensure the dimensional accuracy of the casting in the lateral direction.

The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the casting is a cylinder head of a multi-cylinder engine, and the core is a water cylinder extending above the exhaust port in the cylinder arrangement direction. It is characterized by being a jacket core.
According to this configuration, while increasing the positioning accuracy of the thin water jacket core, the thermal expansion of the water jacket core due to the heat of the molten metal is not hindered, and core deformation due to the reaction force generated at the core end portion due to the expansion difference is prevented. can be suppressed.

The invention of claim 5 is the invention of claim 4, wherein the mold comprises a lower mold for forming a combustion chamber of the cylinder head, and the water jacket core spaced apart from the lower mold. , and a feeder portion formed around the water jacket core .
According to this configuration, even when the rate of solidification of the molten metal around the water jacket core slows down due to the riser portion and the amount of thermal expansion increases due to the thermal influence of the molten metal, the thermal expansion of the water jacket core is not hindered and the expansion is increased. It is possible to suppress the deformation of the core due to the reaction force generated at the core end due to the difference.

According to the mold structure of the present invention, even in casting using a long core, it is possible to ensure the dimensional accuracy of the casting while enhancing supportability of the core.

1 is a longitudinal sectional view of a cylinder head cast using a mold according to Example 1. FIG. Fig. 2 is a perspective view of a mold; Fig. 2 is a plan view of a mold; It is a figure explaining the assembly process of a casting_mold|template. It is explanatory drawing of a pouring process. FIG. 10 is a perspective view of the third water jacket core, where (a) is a view from above and (b) is a view from below; FIG. 4 is a vertical cross-sectional view of the mold, where (a) is a cross-sectional view taken along line VII-VII of FIG. 3, and (b) is an enlarged view of the main part of (a). Fig. 4 is a vertical cross-sectional view of the mold, where (a) is a cross-sectional view taken along line VIII-VIII in Fig. 3, and (b) is an enlarged view of the main part of (a); Fig. 4 is a vertical cross-sectional view of the mold, where (a) is a cross-sectional view taken along line IX-IX in Fig. 3, and (b) is an enlarged view of a main part of (a); Fig. 4 is a vertical cross-sectional view of the mold, where (a) is a cross-sectional view taken along the line X-X of Fig. 3, and (b) is an enlarged view of a main part of (a); Fig. 4 is a vertical cross-sectional view of the mold, where (a) is a cross-sectional view taken along line XI-XI in Fig. 3, and (b) is an enlarged view of a main part of (a); Fig. 4 is a vertical cross-sectional view of the mold, where (a) is a cross-sectional view taken along the line XII-XII of Fig. 3, and (b) is an enlarged view of a main portion of (a); FIG. 4 is an explanatory diagram of a verification experiment model; It is a graph which shows a verification experiment result.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated based on drawing. The following description of preferred embodiments is merely exemplary in nature and is not intended to limit the invention, its applications or uses.

Embodiment 1 of the present invention will be described below with reference to FIGS. 1 to 14. FIG.
The mold of Example 1 is a casting mold for casting a cylinder head 1 of a spark ignition water-cooled in-line four-cylinder engine. The number and arrangement of cylinders of the engine, the ignition method, and the cooling water circulation system are not particularly limited.

First, the cylinder head 1 to be manufactured (finished casting) will be described.
A cylinder head 1 is made of an aluminum alloy material and mounted on a cylinder block of an engine via a gasket (not shown).
As shown in FIG. 1, a cylinder head 1 has a combustion chamber 2 formed in a pent roof-shaped concave portion at the lower end portion and communicates with the combustion chamber 2 via an intake valve (not shown), and is gently slid toward the left. An intake port 3 extending in a curved shape, an exhaust port 4 communicating with the combustion chamber 2 through an exhaust valve (not shown) and extending in a gently curved shape toward the right, and left and right extending in the upper part of the cylinder head 1 in the front and rear direction. It is provided with two camshafts 5, first to third water jackets 6 to 8, an oil jacket 9, and the like extending longitudinally in the lower half of the cylinder head 1. As shown in FIG.
Hereinafter, in the drawings, the side of the front baseboard 31 (see FIG. 6) in the longitudinal direction indicated by arrow F is the front side, the intake side in the lateral direction indicated by arrow L is the left side, and the upper side in the vertical direction indicated by arrow U is the upper side. described as.

The first to third water jackets 6 to 8 are passages for cooling water for the engine.
A pair of first water jackets 6 are formed in the vicinity of the top and left and right sides of the combustion chamber 2 and below the intake and exhaust ports 3 and 4, respectively. The third water jacket 8 is formed on the right side of the jacket 6 and below the exhaust port 4 , and the third water jacket 8 is formed above the second water jacket 7 with the exhaust port 4 interposed therebetween. The oil jacket 9 is a passage portion for flowing engine cooling oil. The oil jacket 9 is formed in the upper space of the upper partition wall of the combustion chamber 2 .

Next, a mold 10 for casting the cylinder head 1 will be described.
As shown in FIGS. 2, 3, and 4, the mold 10 includes a metal cooling plate 11 (lower mold), a cover 12 (upper mold), a base 13, a front wall portion 14, and the front wall portion. 14, and left and right walls 16 and 17 facing each other, and are configured in a substantially rectangular parallelepiped shape having a space inside. A cooling plate 11 forming the bottom of the mold 10 has the spatial shape of the combustion chamber 2 . Except for the base 13, which is formed into a square-shaped frame, each of the walls 12, 14 to 17 of these constituent members is formed as a substantially plate-like structure.

Inside the mold 10 are provided intake/exhaust port cores 21 and 22 for forming the shape of the intake/exhaust ports 3 and 4, an oil jacket core 23 for forming the shape of the oil jacket 9, and a head cover. A first head cover core 24 for forming the surface, a second head cover core 25 for forming the side surface shape of the head cover, and a second water jacket core 26 for forming the shape of the second water jacket 7. , and a third water jacket core 30 (core) for forming the shape of the third water jacket 8 is assembled.
A riser portion 18 (see FIG. 5) is formed in a space formed by the cover 12 (upper mold), the first head cover core 24 and the second head cover core 25 .
The third water jacket core 30 is arranged at a predetermined distance above the cooling plate 11 , and the second head cover core 25 forms the feeder portion 18 (see FIG. 5 ) around the third water jacket core 30 . formed.

Components 12, 14 to 17, 21 to 26, 30 of mold 10, excluding cooling plate 11, are molded by, for example, a cold box molding method.
In the cold box mold method, after kneading foundry sand and a room temperature curing binder (for example, a caking agent such as phenolic resin), the mixture is formed into a predetermined shape to form an intermediate body for each constituent member. Since the molding sand is hardened at room temperature by passing amine gas through these intermediates, the cold box mold method has a shorter molding cycle and higher productivity than the shell mold method.

Next, the process of assembling the mold 10 will be described.
As shown in FIG. 4, each component of the mold 10 is assembled to a base 13 mounted on a cooling plate 11 serving as a base.
First, the second water jacket core 26 extending back and forth is assembled to the base 13 ((b)). Next, the intake port core 21 is installed on the left side of the base 13, and the exhaust port core 22 is installed above the second water jacket core 26 and on the right side of the base 13 ((c)). A third water jacket core 30 that extends from the front end to the rear end of the base 13 is assembled on the upper side of the exhaust port core 22 ((d)).

Next, the front wall portion 14 and the rear wall portion 15 are assembled from above to the front end portion and the rear end portion of the base 13 so as to face each other ((e)), and the left wall portion 16 and the right wall portion 17 face each other. are assembled to the left end portion and the right end portion of the base 13 respectively from above ((f)). The oil jacket core 23 is installed in the center portion of the front wall portion 14 and the rear wall portion 15 in the left-right direction ((g)), and the first head cover core 24 is mounted on the front and rear walls so as to be positioned above the oil jacket core 23 . It is assembled to the parts 14, 15 and the right wall part 17 ((h)). After installing the second head cover core 25 with a set of filters attached to the sprue on the top of the front, rear, left, and right walls 14 to 17 ((j)), the cover 12 is assembled so as to block the upper opening ((k)). .

Next, the pouring process will be described.
As shown in FIG. 5, molten metal (molten metal) is supplied (pouring) by the casting apparatus M to the mold 10 that has finished the assembly process (mold set).
The casting apparatus M includes a casting apparatus 40, a reversing apparatus (not shown) for the mold 10, and the like.
The casting apparatus 40 has, as main components, a holding furnace 41 that stores molten aluminum alloy, an electromagnetic pump 42 that can supply the molten metal to the mold 10, and the like. The pump 42 has a suction nozzle around which a heater means is arranged, and a pouring part rotatably connected to the sprue of the second head cover core 25 via a filter.

In the pouring step, the mold 10 is placed in an initial position inverted by 180°, specifically, in a state where the cooling plate 11 is placed on the upper end of the mold 10 .
Molten metal is supplied to the mold 10 arranged at the initial position, and when the mold 10 is substantially filled with the molten metal, the molten metal is in contact with the cooling plate 11 having a high heat transfer coefficient. The molten metal in the upper part cools faster than the molten metal located in other parts.
After the molten metal is filled, the mold 10 is turned over by 180° using a turning device at a predetermined timing.
As a result, the cooling plate 11 moves downward while the molten metal having a lower temperature than the other portions is held at a position corresponding to the upper portion of the mold 10, so that the second water jacket core 26 disposed near the cooling plate 11 The solidification speed of the molten metal is increased, the amount of thermal expansion of the second water jacket core 26 is small, and deformation is suppressed.

Next, the third water jacket core 30 will be described.
As described above, the third water jacket core 30 is a core for forming the third water jacket 8 extending substantially straight forward and backward (in the cylinder arrangement direction) above the exhaust port 4 . As shown in FIG. 6, the third water jacket core 30 includes a main body 30a having the same shape as the third water jacket 8, and a front baseboard 31 (first end baseboard) provided at the front end of the main body 30a. ), a rear baseboard 32 (second end baseboard) provided at the rear end of the main body 30a, an intermediate baseboard 33 provided in the middle of the main body 30a (for example, the center in the front-rear direction), and the like. It has

The front baseboard 31 is formed to extend forward from the front end of the main body 30a.
As shown in FIGS. 6, 7 and 10, the front baseboard 31 is surrounded by the base 13, the front wall portion 14 and the second water jacket core 26. As shown in FIGS. The front baseboard 31 has a front end portion formed with a convex portion 31a protruding downward. The protrusion 31 a is engaged with a first recess 13 a formed in the base 13 .

As shown in FIGS. 7B and 10B, the front wall portion of the projection 31a faces the front wall portion of the first recess 13a with a minute gap (for example, 1 mm) therebetween. The wall faces the front wall of the second water jacket core 26 with a small gap therebetween. The lower wall portion of the convex portion 31a is supported in surface contact with the bottom wall portion of the first concave portion 13a, and the upper wall portion has a small gap (for example, 0.5 mm) with respect to the lower wall portion of the front wall portion . facing through. The left and right wall portions of the convex portion 31a are in surface contact with and restrained by the left and right wall portions of the first recess portion 13a. As a result, the front baseboard 31 can move back and forth, and its lateral movement is restrained.

The rear baseboard 32 is formed to extend rightward from the rear end of the main body 30a.
As shown in FIGS. 6, 8 and 11, the rear baseboard 32 is surrounded by the base 13 and the right wall portion 17. As shown in FIGS. A concave portion 32a is formed in the lower portion of the rear side baseboard 32 so as to be recessed upward. The concave portion 32 a is engaged with a convex portion 13 c formed on the base 13 .

As shown in FIGS. 8(b) and 11(b), the lower wall of the rear baseboard 32 is in surface contact with and supported by the upper wall of the base 13, and the upper wall of the right wall 17 is supported. It faces the lower wall of the via a small gap (for example, 0.5 mm). The front and rear walls of the concave portion 32a are opposed to the front and rear walls of the right wall portion 17 with a minute gap (for example, 0.5 mm) therebetween, and the lower wall portion faces the upper wall portion of the convex portion 13c. supported in contact. The left and right walls of the concave portion 32a are in surface contact with the left and right walls of the convex portion 13c and are restrained. As a result, the rear baseboard 32 can move back and forth, and its lateral movement is restrained.

The intermediate baseboard 33 is formed so as to extend rightward from the middle portion of the main body 30a.
As shown in FIGS. 6, 9 and 12, the intermediate baseboard 33 is surrounded by the base 13, the right wall portion 17 and the exhaust port core 22. As shown in FIGS. The intermediate baseboard 33 includes a lower end portion 33a (wedge-shaped portion), a stepped portion 33b, an intermediate portion 33c, and an upper end portion 33d.
The lower end portion 33a is formed in a substantially wedge shape, which is set smaller in front-rear and left-right dimensions than the intermediate portion 33c, and has smaller front-rear and left-right dimensions toward the bottom. This lower end portion 33 a is engaged with a second recess 13 b formed in the base 13 . The intermediate portion 33 c is formed to have a substantially wedge-shaped left-right cross section, and the upper end portion 33 d is engaged with a concave portion 17 a formed in the right wall portion 17 .

The front and rear walls and the left and right walls of the lower end portion 33a are restrained in surface contact with the front and rear walls and the left and right walls of the second recess 13b. By supporting the stepped portion 33b on the top of the second recessed portion 13b and bringing the upper end portion 33d into surface contact with the lower wall portion of the right wall portion 17 (recessed portion 17a), the vertical movement of the intermediate baseboard 33 is restrained. there is As a result, the intermediate baseboard 33 is restrained from moving forward, backward, left, right, and up and down. The lower end portion 33a, the stepped portion 33b, and the upper end portion 33d corresponding to the lower end portion 33a correspond to the engaging portion of the present invention.

Next, the function and effects of the mold 10 will be described.
In order to explain the action and effect, comparative example models M1 to M3 and an example model M4 having the same specifications as Example 1 were prepared, and a verification experiment related to thermal expansion deformation of the models M1 to M4 was performed using CAE (Computer Aided Engineering). went.

13(a) to 13(d) show the specifications of the models M1 to M4.
In the model M1, the front baseboard is formed on the front side of the front end of the main body, the rear baseboard is formed on the right side of the rear end of the main body, and the intermediate baseboard is formed on the right side of the central part of the main body. All baseboards are constrained to move forward, backward, left, right, up and down.
In the model M2, the front baseboard is formed on the front side of the front end of the main body, the rear baseboard is formed on the rear side of the rear end of the main body, and the intermediate baseboard is formed on the right side of the central part of the main body. All baseboards are constrained to move forward, backward, left, right, up and down.
The model M3 has a front baseboard on the right side of the front end of the body, a rear baseboard on the right side of the rear end of the body, and an intermediate baseboard on the right side of the center of the body. All baseboards are constrained to move forward, backward, left, right, up and down.
In the model M4, the front baseboard is formed on the front side of the front end of the main body, the rear baseboard is formed on the right side of the rear end of the main body, and the intermediate baseboard is formed on the right side of the central part of the main body. The front and rear baseboards are movable back and forth, and the intermediate baseboard is restrained in front, back, left, right, and up and down movements.
A temperature equivalent to the time of pouring was given to the models M1 to M4, and the average value of the thermal expansion deformation amount (X, Y, Z) (mm) in the front, back, left, right, up and down directions at a plurality of measurement points was analyzed.

FIG. 14 shows the analysis results.
In the longitudinal direction (X), except for model M2 (1.5 mm), model M1 (0.6 mm), model M3 (0.7 mm), and model M4 (1.0 mm) had approximately the same amount of deformation. .
In the left-right direction (Y), except for model M1 (0.5 mm) and model M2 (1.7 mm), model M3 (0.3 mm) and model M4 (0.1 mm) had approximately the same amount of deformation. .
In the vertical direction (Z), the deformation amount of the model M4 (0.1 mm) was much smaller than the model M1 (1.6 mm), the model M2 (0.6 mm), and the model M3 (1.1 mm).
As described above, it was confirmed that the embodiment model M4 has a smaller amount of thermal expansion deformation than the comparative example models M1 to M3.

According to this mold structure, the front and rear baseboards 31 and 32 supported by the mold 10 (base 13) and the intermediate baseboard 33 are provided at the front and rear end portions and the intermediate portion of the third water jacket core 30, respectively. , the front and rear baseboards 31 and 32 are supported by the mold 10 so as to be movable in the front-rear direction. It is possible to avoid problems such as breakage of the third water jacket core 30 caused by the difference in the amount of thermal expansion between the third water jacket core 30 and the third water jacket core 30 .
The intermediate baseboard 33 is supported by the mold 10 via a lower end portion 33a, a stepped portion 33b, and an upper end portion 33d corresponding to the lower end portion 33a as an engaging portion capable of restricting movement in the front, rear, left, right, and up and down directions. Therefore, the difference in the amount of thermal expansion generated between the mold 10 and the third water jacket core 30 can be dispersed to both end portions of the third water jacket core 30, and the mold 10 and the third water jacket core 30 can be dispersed. Displacement of the relative positional relationship with the 3-water jacket core 30 can be suppressed over the entire front-rear direction.

The engaging portion has a wedge-shaped lower end portion 33a in cross section, and the mold 10 (base 13) has a second concave portion 13b that can be engaged with the engaging portion. The movement of the third water jacket core 30 in the front, rear, left, and right directions with reference to the intermediate portion can be constrained with a simple configuration.

Since the front and rear baseboards 31 and 32 are restrained from moving in the left and right direction and are arranged so as to be offset in the left and right direction when viewed from the front and rear direction, the front and rear baseboards 31 and 32 thermally expand. The amount of deformation can be offset by each, and the dimensional accuracy of the casting 10 in the left-right direction can be ensured.

The casting is the cylinder head 1 of the multi-cylinder engine, and the core is the third water jacket core 30 extending in the cylinder arrangement direction above the exhaust port 4, so the positioning of the thin third water jacket core 30 The thermal expansion deformation of the third water jacket core 30 due to the heat of the molten metal can be suppressed while improving the accuracy.

A mold 10 is a cooling plate 11 formed of a mold for forming the combustion chamber 2 of the cylinder head 1, and a feeder portion 18 formed in the vicinity of the third water jacket core 30 spaced apart from the cooling plate 11. Therefore, even when the solidification speed of the molten metal around the third water jacket core 30 is slowed by the riser portion 18 and the amount of thermal expansion increases due to the thermal influence of the molten metal, the thermal expansion of the third water jacket core 30 deformation of the third water jacket core 30 due to the reaction force generated at the end of the third water jacket core 30 due to the expansion difference can be suppressed.

Next, a modified example in which the above embodiment is partially changed will be described.
1) In the above embodiment, an example in which the casting is the cylinder head 1 has been described, but any casting having at least a longitudinal direction and a transverse direction and having a core extending in the longitudinal direction can be applied arbitrarily. Is possible. Moreover, in the case of the cylinder head 1, the number of cylinders, the model of the engine, etc. are arbitrary.

2) In the above embodiment, an example in which the third water jacket core 30 is assembled to the base 13 has been described. It may be directly attached to the mold, or it may be attached to the front wall portion and the rear wall portion.

3) In addition, those skilled in the art can implement various modifications to the above-described embodiment or combinations of the embodiments without departing from the scope of the present invention. Any modifications are also included.

1 Cylinder head 2 Combustion chamber 4 Exhaust port 11 Cooling plate 13b Second recess 18 Feeder 30 Third water jacket core 31 Front baseboard 32 Rear baseboard 33 Intermediate baseboard 33a Lower end 33b Step 33d Upper end

Claims (5)

A mold structure comprising a mold for casting a casting and a core disposed in the mold for forming a passage extending longitudinally of the casting,
First and second end baseboards and an intermediate baseboard supported by the mold are provided at both longitudinal ends and a longitudinal intermediate part of the core, respectively;
The first and second end baseboards are movably supported in the mold in the longitudinal direction,
A mold structure, wherein the intermediate baseboard is supported by the mold through engaging portions that restrict movement in the longitudinal direction, the transverse direction orthogonal to the longitudinal direction of the casting, and the vertical direction. The engaging portion has a wedge-shaped cross section orthogonal to the longitudinal direction and the lateral direction,
The mold structure according to claim 1, wherein the mold has a recess that engages with the engaging portion. 2. The first and second end baseboards are restrained from moving in the lateral direction, and arranged so as to be offset in the lateral direction when viewed from the longitudinal direction. or the template structure according to 2. 4. The casting according to any one of claims 1 to 3, wherein the casting is a cylinder head of a multi-cylinder engine, and the core is a water jacket core extending above the exhaust port in the direction in which the cylinders are arranged. Template structure as described. The mold is a lower mold that forms the combustion chamber of the cylinder head, the water jacket core is spaced apart from the lower mold , and the riser is formed around the water jacket core. 5. The mold structure of claim 4, comprising a portion.