JPH0852560A - Manufacture of column for preventing advancement of vehicle - Google Patents

Abstract

PURPOSE:To manufacture a columnar body with improved strength at a low manufacturing cost by casing the metallic material for casting so as to surround a columnar reinforcing member from the outside to form a body part of hollow tubular shape which is externally fitted to the reinforcing member. CONSTITUTION:A pattern of the same shape as that of a body part 2 is manufactured by using the foaming resin, and a reinforcing member 3 consisting of a steel tube is inserted into a hole in this pattern. The casting sand is filled in the inner space of the pattern into which the reinforcing member 3 is inserted, the pattern is arranged in a flask to which the reinforcing member is assembled, and the casting sand is filled outside thereof to embed the pattern. When the molten metal is poured, the molten metal flows in while losing the pattern. When the casting is taken out of the cooled flask, a columnar body 1 of the shape where the body part 2 of the same shape as that of the lost foam pattern is externally fitted to the reinforcing member 3 is obtained. The columnar body 1 which is manufactured only by the process corresponding to the conventional one, and dispenses with the machining, etc., after the casting, and whose strength is improved is obtained more inexpensively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a vehicle entrance preventing pillar provided on an entrance or sidewalk of a parking lot, a school, a park or the like to prevent a vehicle from entering.

[0002]

2. Description of the Related Art At entrances to parks and roads exclusively for pedestrians,
In order to prevent entry of a vehicle, a vehicle entry prevention columnar body (hereinafter abbreviated as columnar body) 20 as shown in FIG.
It stands on the ground 19 at appropriate intervals. The one shown in the figure is made of a casting metal material such as an aluminum alloy or cast iron, and is formed into a hollow columnar shape having a closed upper end. The pillar 20 is a concrete block 2 buried in the ground.
It is fixed to the No. 1 by an anchor bolt 22.

By the way, when the columnar body 20 is made of aluminum alloy or the like, it is necessary to make it thicker in order to secure the required strength. Therefore, the manufacturing cost is high. On the other hand, for example, as shown in FIG. 10A, a reinforcing member 23 made of a steel pipe is provided inside, and the reinforcing member 23 is
Main body 2 made of thinner aluminum alloy
A vehicle entrance preventing pillar having a structure in which 4 is fitted is manufactured.

In this case, first, the reinforcing member 23 is placed on the ground 19.
Is erected, and then the main body 24 is externally fitted from above. Then, as shown in FIG.
The upper surface of the reinforcing member 23 and the flange on the inner surface of the main body portion 24 are mutually connected by. After that, the upper end opening of the main body 24 is sealed with a lid 27, and the lid 27 is fixed with a screw 28, so that this type of column is installed.

However, in the above structure, the reinforcing member 23, the main body 24, and the lid 27 are individually manufactured, and it is necessary to assemble them at the installation site, and the number of parts to be managed individually. Because there are many
The workability of the installation work is reduced, and the management of parts becomes complicated.

Therefore, as shown in FIG. 11, for example, a reinforcing member 32 made of a steel pipe is inserted into a main body 31 made of an aluminum alloy through a lower end opening of the main body 31, and a column for preventing vehicle entrance having a double pipe structure. The body is also made. In this case, the inner peripheral surface of the main body portion 31 is provided with a ring-shaped inward protruding portion that is fitted to the outer periphery of the reinforcing member 32 on the upper end side thereof. On the other hand, in the underground portion, the main body 31 and the reinforcing member 32 are connected to each other on the lower end side by penetrating the columnar fixing metal fittings 33 through both the main body 31 and the reinforcing member 32.
As a result, both 31 and 32 are fixed to each other. In this configuration, the main body 31 and the reinforcing member 3
2 can be assembled in advance, which improves the workability of installation on site.

[0007]

However, in the structure in which the reinforcing member 32 is inserted and fitted into the main body 31 as described above, the main body 31 is lengthened to the underground portion,
It is necessary to establish a connection state with the reinforcing member 32 by the pillar fixing metal fitting 33. For this reason, the total length of the main body portion 31 becomes long, and it takes a lot of man-hours to manufacture a casting, which causes a problem of high manufacturing cost. Further, when casting a columnar body having a closed upper end, it is difficult to support a long core in a cantilevered state at an accurate position. Therefore, there is a problem that uneven thickness is likely to occur and the strength of the main body 31 is locally reduced.

On the other hand, when it is attempted to obtain a predetermined fitting accuracy with respect to the inserted reinforcing member 32 on the upper end side, the inner projecting portion of the inner peripheral surface of the main body 31 is post-processed and the reinforcing member is inserted. It is also necessary for the 32 to fit smoothly, which also increases the manufacturing cost.

The present invention has been made in view of the above-mentioned conventional problems, and has the required strength and excellent quality.
Moreover, it is an object of the present invention to provide a method for manufacturing a vehicle entrance preventing pillar that can be manufactured at a lower cost.

[0010]

According to a first aspect of the present invention, there is provided a method for manufacturing a vehicle entrance preventing pillar, which is a pillar-shaped vehicle entrance preventing pillar which is erected on the ground. It is characterized in that a hollow metal tube-shaped main body part externally fitted to the reinforcing member is formed by casting a casting metal material so as to surround the member from the outside.

According to a second aspect of the present invention, there is provided a method for manufacturing a vehicle entrance preventing pillar body according to the first aspect, wherein a portion of the reinforcing member that is fitted to the inner surface of the main body is a reinforcing member during a casting cooling process. The present invention is characterized in that a cushioning member that absorbs a difference in shrinkage deformation amount with the main body is provided.

According to a third aspect of the present invention, there is provided a method for manufacturing a vehicle entrance preventing column body according to the first or second aspect of the present invention, wherein a model of the main body is made of a material that disappears when pouring a molten metal material for casting. Along with, by inserting a reinforcing member into this model, after that, the model is placed in a casting frame and after filling the space with casting sand, by pouring the molten metal material for casting into the model part, It is characterized in that a main body part externally fitted to the reinforcing member is formed.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a vehicle entrance preventing column body according to the third aspect of the present invention, wherein a reinforcing member to be inserted is partially provided on an inner peripheral surface of the model. It is characterized in that a fitting support portion locally protruding inward is provided so as to be in a fitted state.

[0014]

In the manufacturing method according to the first aspect of the present invention, the hollow-tube-shaped main body portion externally fitted to the reinforcing member is formed by casting a metal material for casting so as to surround the reinforcing member from the outside. In this case, the pillar body having the reinforcing member inside is produced only by the process corresponding to the conventional casting process, and the conventional assembling work of the reinforcing member and the post-processing after casting necessary for this are unnecessary. Thus, a column body having improved strength can be manufactured at a lower cost.

Further, since the fitting portion between the reinforcing member and the main body portion can be provided over an arbitrary portion and width in the longitudinal direction, it is necessary to have a structure in which the main body portion is extended to the underground portion and connected as in the conventional case. Instead, for example, the length of the main body portion can be set to a length corresponding to only the ground portion. As a result, during casting, it is possible to perform casting with the reinforcing member accurately supported as a core, and as a result, uneven thickness is less likely to occur in the main body, and a high-quality columnar body with uniform strength throughout is manufactured. can do.

In the manufacturing method according to the second aspect, the cushioning member is provided at the fitting portion of the reinforcing member with the inner surface of the main body. In this case, for example, when the metal material for casting is an aluminum alloy or the like for the reinforcing member made of an iron-based material,
Due to the difference in the coefficient of thermal expansion, a difference in the amount of shrinkage occurs during casting cooling,
A crack or a crack is generated in the main body made of an aluminum alloy. However, in the above, since such a difference in the amount of shrinkage is absorbed by the above-mentioned cushioning member, cracks and cracks do not occur and a column body of excellent quality is produced.

In the manufacturing method according to the third aspect, a method of forming a model of the main body with a material that disappears by pouring the molten metal material for casting and casting, that is, a so-called disappearance model casting method, A main body whose inside is reinforced with a reinforcing member is manufactured. In this case, even if there is a space between the inner surface of the model and the reinforcing member inserted at this point, it is possible to cast a main body part having the same shape as the model by filling this part with sand. You can That is, even if the inner surface of the main body has, for example, a circular cross section, the reinforcing member should have an arbitrary shape such as a rectangular cross section as long as it has a shape that partially fits and fits the inner surface of the main body. Is possible. As a result, in addition to steel pipes, for example, lightweight structural steels for general structures, welded lightweight H-shaped steels for general structures, and the like can be used, and the range of selection as a reinforcing member is widened, which also reduces the manufacturing cost. .

In the manufacturing method according to the fourth aspect, the fitting support portion locally protruding inward so that the reinforcing member to be inserted is partially fitted to the inner peripheral surface of the model. Is provided. In this case, the wall thickness of the main body portion becomes thinner in the area other than the fitting support portion, whereby the amount of the casting metal material used can be reduced,
Manufacturing costs are cheaper. Further, when the cushioning member is provided at the fitting portion between the main body and the reinforcing member, the amount of the cushioning member used can be small, so that the manufacturing cost can be further reduced.

[0019]

【Example】

[Embodiment 1] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. As shown in FIG. 1 (a), a vehicle-entry prevention pillar body (hereinafter abbreviated as a pillar body) 1 according to the present embodiment includes a main body portion 2 which is an exposed portion on the ground, and a main body portion 2 which is disposed in the main body portion 2. The reinforcing member 3 is provided, and the column body fixing fittings 4 and 4 are attached to the lower end side of the reinforcing member 3.

The main body 2 has a cylindrical shape with its upper end sealed, and is made of, for example, an aluminum alloy for casting. The reinforcing member 3 is configured by using a cylindrical steel pipe, and has a length shape that extends in the main body portion 2 for almost the entire length except for the vicinity of the upper end portion thereof, and projects further downward from the lower end of the main body portion 2. ing. On the lower end side of this projecting portion, two pillar body fixing fittings 4 and 4 are penetrated in a cross shape as shown in FIG. 1 (b), and by embedding this projecting portion in the ground, The body 1 is fixed to the ground 5 vertically.

Next, the above-mentioned pillar 1 using the vanishing model casting method
The manufacturing of will be described with reference to FIG.

First, as shown in FIG. 2A, a model (hereinafter referred to as a vanishing model) 6 having the same shape as the main body 2 is produced by using a foamed resin, and the vanishing model 6 is provided with an internal hollow hole. The reinforcing member 3 made of steel pipe is inserted. As shown in FIG. 3B, the reinforcing member 3 has a hole 4a at the upper end side thereof through which the pillar fixing fitting 4 penetrates.
Are formed in advance.

Next, the internal space of the vanishing model 6 in which the reinforcing member 3 is inserted as described above is filled with the casting sand 7. After that, as shown in FIG. 3C, the vanishing model 6 to which the reinforcing member 3 is attached is placed in the casting frame 8 and the casting sand 7 is also provided outside thereof.
Are filled to obtain an embedded state. Then, when the molten metal 9 is poured through the gate, the molten metal 9 flows while the disappeared model 6 disappears. As a result, the space occupied by the disappearance model 6 is replaced by the molten metal 9.

After cooling, when taken out from the form 8, a column 1 having a shape in which a main body 2 having the same shape as the vanishing model 6 is externally fitted to the reinforcing member 3 as shown in FIG. can get.

As described above, in the manufacturing method of the present embodiment, the hollow tube-shaped main body 2 fitted on the reinforcing member 3 is
Since it is manufactured only by the process corresponding to the conventional casting process, and the conventional assembling work of the reinforcing member and the post-processing after casting necessary for this are not necessary, the pillar body 1 with improved strength can be manufactured at a lower cost. can do.

Further, since the fitting of the main body 2 and the reinforcing member 3 can be obtained over a sufficient length region, in order to make the integrated structure of the two and 3 more solid, the main body as in the conventional case is required. It is not necessary to have a structure in which the parts are extended to the underground part and connected. For this reason, the length of the main body 2 can be shortened to a length corresponding to only the above-ground portion, so that uneven thickness is unlikely to occur in the main body 2, and a high-quality columnar body 1 having uniform strength over the whole is provided. Can be made.

[Embodiment 2] Another embodiment of the present invention will be described below with reference to FIG. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

The columnar body 1 according to this embodiment is shown in FIGS.
As shown in, the cushioning member 3a is wound around the outer periphery of the reinforcing member 3. The cushioning member 3a is made of a material having a high heat resistant temperature such as ceramic fiber, and is formed in a cloth shape that can shrink in the thickness direction.

The pillar 1 is assembled by inserting the reinforcing member 3 having the cushioning member 3a on the outer peripheral surface thereof into the central hole of the vanishing model produced in the same manner as in the above-mentioned embodiment, and thereafter as in the above-mentioned embodiment. It was produced by filling the inside and outside of the vanishing model with casting sand, arranging it in the flask, and pouring the molten aluminum alloy.

In this embodiment, it is possible to prevent the occurrence of cracks and cracks in the main body portion 2 which are apt to occur during cooling after casting. That is, the reinforcing member 3 made of a steel pipe and the main body 2 made of an aluminum alloy conventionally have cracks or cracks in the main body due to the difference in the amount of shrinkage during cooling of the casting due to the difference in the coefficient of thermal expansion. However, in the above, since such a difference in the amount of shrinkage is absorbed by the cushioning member 3a, there is no occurrence of cracks or cracks, and the column body 1 having excellent quality is manufactured.

Further, since the buffer member 3a acts as a heat insulating material, the heat dissipation through the reinforcing member 3 when the aluminum alloy is cast is reduced, and the temperature drop during the cooling of the molten metal becomes more uniform, so that the casting Sexuality is improved, which in turn
Productivity is improved.

[Third Embodiment] The following description will explain still another embodiment of the present invention with reference to FIG. In addition,
For convenience of explanation, members having the same functions as the members shown in the drawings of the above-described respective embodiments are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 4 (a), in the columnar body 1 according to this embodiment, a plurality of fitting support portions 2a ... Inwardly protruding are provided on the inner peripheral surface of the main body portion 2, The same cushioning members 3a as described above are provided on the inner surfaces of the fitting support portions 2a.
The circular tubular reinforcing member 3 is in a fitted state via.

The fitting support portions 2a ... Are formed at three locations in the vertical direction, and at four locations in the circumferential direction, as shown in FIG. In this case, the buffer member 3a ...
Are formed in a piece shape corresponding to the inner surface shape of each fitting support portion 2a.

This column 1 is also manufactured by the vanishing model casting method as in each of the above-mentioned embodiments. First, a vanishing model corresponding to the shape of the main body 2 is produced, and the inner surface of this vanishing model is produced. The cushioning members 3a are attached to the inner surfaces of the protrusions corresponding to the fitting support portions 2a.

After that, the reinforcing member 3 is inserted into the inside, and thereafter, as in the above-mentioned embodiment, the inside and outside of the vanishing model are filled with casting sand and placed in the flask, and the molten aluminum alloy is poured into the inside of the vane. The pillar 1 is produced.

In the case of this embodiment, the fitting support portions 2a ... Which locally project inward are formed on the inner surface of the main body portion 2 so that the main body portion 2 and the internal reinforcing member 3 are partially fitted. It is provided in. For this reason, the wall thickness of the main body portion 2 becomes thinner in the region other than the fitting support portion 2a, and thus the amount of the casting metal material such as the aluminum alloy used can be reduced, so that the manufacturing cost can be reduced. Will be cheaper.

Further, the cushioning member 3a is also the reinforcing member 3.
It suffices to provide it only on the portion of the fitting support portion 2a that is in contact with, and the amount of expensive fire-resistant material such as ceramic fiber forming the cushioning member 3a can be reduced, so that the manufacturing cost can be further reduced. Become.

Further, since the main body 2 is supported by the fitting support portions 2a, the shape of the reinforcing member 3 is within the main body 2, for example, as shown in FIG. Even if 2 is a taper shape, by changing the shape or size of the fitting support portions 2a ... As shown in FIGS. In addition to maintaining the same, the reinforcing member 3 can be an ordinary steel pipe or the like, so that cost reduction can be achieved.

In addition, since the contact area between the main body portion 2 and the reinforcing member 3 can be made smaller by providing the fitting support portion 2a as described above, heat between the main body portion 2 and the reinforcing member 3 can be reduced. The difference in expansion coefficient does not affect as much as Example 2,
As shown in FIG. 5, the buffer member 3a may not be necessary in some cases. On the other hand, in order to fill and discharge the molding sand into the space between the main body 2 and the reinforcing member 3, the reinforcing member 3 may be provided with an opening.

Although a circular tube is used as the reinforcing member 3 in accordance with the cross-sectional shape of the main body 2 in each of the above-mentioned embodiments, the cross-section does not necessarily have to be circular. For example, as shown in FIG. b) and FIG. 4B in Example 3 may use a reinforcing member 3 having a rectangular cross section for the main body 2 having a polygonal cross section as shown in FIGS. 6 and 7, respectively. As long as they are close to each other, the reinforcing member 3 having an arbitrary shape can be adopted. Here, in FIG.
The case where the above-mentioned buffer member is not used is shown.

In particular, in the case of manufacturing by the disappearing model casting method as in each of the above-mentioned embodiments, even if a space is formed between the inner surface of the model and the reinforcing member inserted in this part, this part is also formed. By filling the mold with sand, the main body having the same shape as the model can be cast. That is, even when the inner surface of the main body has a circular cross section, for example, as the reinforcing member,
If the shape is such that the inner surface of the main body partly touches and fits,
An arbitrary shape such as a rectangular cross section can be used. As a result, in addition to steel pipes, for example, lightweight structural steels for general structures, welded lightweight H-shaped steels for general structures as shown in FIG. 8 and the like can be used, and the selection range as a reinforcing member expands. Expenses will be cheaper.

Further, in this casting method, it is easy to remove the mold after casting, so that the structure of the production line can be simplified.

In each of the above embodiments, the example of manufacturing the main body 2 by the vanishing model casting method is given. However, within the scope of claim 1 or 2 of the present invention, other casting methods such as cavity casting method are used. In addition to the aluminum alloy, other materials such as ordinary cast iron (FC) and spheroidal graphite cast iron (FCD) can be used as the metal material for casting.

[0045]

As described above, in the method for manufacturing the vehicle entrance preventing pillar according to the first aspect of the present invention, the casting metal material is cast so as to surround the pillar-shaped reinforcing member from the outside. This is a configuration in which a hollow tube-shaped main body portion externally fitted to the reinforcing member is formed.

As a result, since the column body having the reinforcing member for reinforcement therein is produced only by the step corresponding to the conventional casting step, the column body having the improved strength can be produced at a lower cost. be able to. Further, for example, even if the length of the main body portion corresponds to only the above-ground portion, a sufficient integrated structure with the reinforcing member can be obtained, and the main body portion can be made shorter, so that the main body portion has uneven thickness. The effect is that it is possible to manufacture a high-quality columnar body that is unlikely to occur and whose strength is uniform throughout.

According to a second aspect of the present invention, there is provided a method for manufacturing a vehicle entrance preventing pillar, wherein a difference in shrinkage deformation amount between the reinforcing member and the main body portion during the casting and cooling process is provided in a fitting portion of the reinforcing member with the inner surface of the main body portion. This is a configuration in which a cushioning member that absorbs is absorbed.

This prevents cracks and cracks from being generated during cooling of the casting due to the difference in the coefficient of thermal expansion between the reinforcing member and the main body, so that an excellent quality column can be produced. .

According to a third aspect of the present invention, there is provided a method for manufacturing a vehicle entrance preventing pillar, in which a model of a main body is made of a material that disappears when a molten metal material for casting is poured, and a reinforcing member is fitted into the model. After that, the model is placed in a molding frame, the space is filled with sand, and then the molten metal of the casting metal material is poured into the model part to form the main body part fitted on the reinforcing member. This is the configuration.

As a result, as the reinforcing member, it is possible to use an arbitrary shape such as a rectangular cross section as long as the reinforcing member has a shape that is partially in contact with the inner surface of the main body. As a result, for example, lightweight structural steel for general structure, welded lightweight H-shaped steel for general structure, etc. can be used, and the range of selection as the reinforcing member is widened, whereby the manufacturing cost can be made lower. It has the effect of being able to.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a pillar for vehicle entrance prevention, in which the reinforcing member to be inserted is locally fitted inwardly on the inner peripheral surface of the model. This is a configuration in which a protruding fitting support portion is provided.

As a result, the wall thickness of the main body portion becomes thinner in the region other than the fitting support portion, whereby the amount of cast metal material used can be reduced.
This also makes the manufacturing cost cheaper. Furthermore, when the cushioning member is provided at the fitting portion of the main body and the reinforcing member, the amount of the cushioning member used can be small,
Further, there is an effect that the manufacturing cost can be reduced.

[Brief description of drawings]

1A and 1B show a vehicle entrance preventing pillar manufactured by applying a manufacturing method according to an embodiment of the present invention, in which FIG. 1A is a vertical sectional view and FIG. FIG. 4B is a cross-sectional view taken along line AA in FIG.

FIG. 2 is a vertical cross-sectional view showing a manufacturing process of the vehicle entrance preventing pillar according to the embodiment of the invention.

FIG. 3 is a view showing a vehicle entrance preventing pillar manufactured by applying a manufacturing method according to another embodiment of the present invention,
The figure (a) is a longitudinal sectional view, and the figure (b) is the figure (a).
6 is a cross-sectional view taken along line BB in FIG.

FIG. 4 is a view showing a vehicle entrance preventing pillar manufactured by applying a manufacturing method according to still another embodiment of the present invention, wherein FIG. 4 (a) is a vertical sectional view, and FIG. 3B) is a cross-sectional view taken along the line CC of FIG.

FIG. 5 is a view showing a vehicle entrance preventing pillar manufactured by applying a manufacturing method according to still another embodiment of the present invention, in which FIG. 6B is a cross-sectional view taken along the line DD of FIG. 7A, and FIG. 7C is a cross-sectional view taken along the line EE of FIG.

6 is a cross-sectional view of the vehicle entrance preventing pillar in which the main body section is polygonal in the vehicle entrance preventing pillar shown in FIG. 3;

FIG. 7 is a cross-sectional view of the vehicle entrance preventing pillar made in the vehicle entrance preventing pillar of FIG. 4 in which the main body section is polygonal and the cushioning member is not provided.

8 shows a vehicle entrance preventing pillar of the vehicle entrance preventing pillar shown in FIG. 7, in which a reinforcing member is made of a welded lightweight H-shaped steel for general structure.

FIG. 9 is a vertical cross-sectional view of a vehicle entrance preventing pillar according to a conventional example.

FIG. 10 is a view showing a vehicle entrance preventing pillar according to another conventional example, in which FIG. 10 (a) is a vertical sectional view and FIG. 10 (b) is an enlarged sectional view of an upper portion of FIG. 10 (a). Is.

FIG. 11 is a vertical cross-sectional view of a vehicle intrusion prevention column according to still another conventional example.

[Explanation of symbols]

 1 Vehicle entry prevention column 2 Main body 2a Fitting support 3 Reinforcing member 3a Cushioning member 4 Column fixing fitting 6 Disappearance model 7 Cast sand 8 Casting frame 9 Molten metal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Hasegawa 726-19 Tanikai, Sanwa-cho, Sarushima-gun, Ibaraki Prefecture (72) Inventor Shiro Kuramoto 1923-15 Tawaraguchi-cho, Ikoma-shi, Nara Inventor Hiramatsu Subaru Kyoto Prefecture 6-255 Sunada, Iseta-cho, Uji City (72) Inventor Toshio Fujimori 2041 Mirror, Ryuo-cho, Gamo-gun, Shiga Prefecture

Claims (4)

[Claims] 1. A method for manufacturing a pillar-shaped vehicle entrance preventing pillar that is erected on the ground, wherein a casting metal material is cast so as to surround the pillar-shaped reinforcing member from the outside, so that the reinforcing member is externally fitted to the reinforcing member. Forming a hollow tube-shaped main body part, the method for manufacturing a vehicle entrance preventing pillar. 2. A cushioning member for absorbing a difference in shrinkage deformation amount between the reinforcing member and the main body during the casting and cooling process is provided at a fitting portion of the reinforcing member with the inner surface of the main body. The method for manufacturing a vehicle entrance preventing pillar according to claim 1. 3. A model of a main body is made of a material that disappears by pouring a molten metal material for casting, and a reinforcing member is fitted into this model, and then the model is placed in a casting frame to create a space. 3. The main body part externally fitted to the reinforcing member is formed by pouring molten metal of the casting metal material into the model portion after filling the casting sand with the casting sand.
A method of manufacturing a column body for preventing vehicle entry as described. 4. A fitting support portion that locally projects inward is provided on the inner peripheral surface of the model so that the reinforcing member to be inserted is partially fitted. Claim 3
A method of manufacturing a column body for preventing vehicle entry as described.