JP3255335B2 - Casting method of cast arm part of gun arm - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for casting a cast character portion of a gun arm used for spot welding.

[0002]

2. Description of the Related Art Generally, in a casting method using a shell mold, a wooden mold (model) having the same shape as a molded product is created.
This wooden mold is transferred to form a half-shell shell mold with upper and lower halves in which a cavity is formed, and a core, a cast-in member, a filter, etc. are assembled, and the upper and lower sand molds are combined. .

In the above-mentioned casting, when characters and marks are expressed as cast characters, characters or the like are formed integrally with a wooden mold, or those formed in irregularities with a die tape or the like are adhered to the wooden mold, and then sand-molded. To make a mold.
In addition, there is a method of engraving characters and marks on the foaming mold.

[0004]

However, when molding a mold without using a wooden mold, or when expressing individual cast characters on a molded product, it is necessary to engrave characters or marks on the mold. However, this engraving operation has to be performed manually depending on the cavity, and improvement in the operation of the mold making process is desired.

[0005]

Means for Solving the Problems To solve the above problems, first, a cavity is formed by shell sand,
In the method for casting a gun arm using a shell mold having a character-shaped portion facing a cavity, the shell mold has a cutout hole formed in a shape obtained by layering a cavity corresponding to a molded product to be cast. Another shell plate and a lower plate forming the bottom of the cutout hole and an upper plate forming a lid are laminated and configured, and the character portion is formed by forming an uneven portion of the concave and convex character prototype with a curable resin on the exposed portion by the character type projection. A residue was formed and a letter mold was formed by transferring the letter mold from the uneven letter mold, and the letter mold was accommodated in the shell plate with a recess formed.

Secondly, in the method of casting a cast character portion of a gun arm according to claim 1, the character mold projects into a cavity beyond a depth of cut when processing a molded product and has a shell. The plate was housed in a recess.

Third, in the method for casting a cast character portion of a gun arm according to claim 1 or 2, the character mold is provided with a cutout hole in a shell plate for each layer of a shell mold having a cavity portion cut out. And formed into a recess.

[0008]

According to a first aspect of the present invention, a method for casting a cast character portion of a gun arm includes laminating a shell plate for each layer having cutout holes and upper and lower plates to form a mold without a wooden mold. The character mold is housed in the recess of the shell plate and faces the cavity, and with this individually configurable mold,
An arbitrary cast character based on the character projection is transferred.

According to a second aspect of the present invention, there is provided a method for casting a cast character portion of a gun arm, wherein a character mold is provided so as to protrude into a cavity, so that a transferred character is located at a sunk position which does not disappear even when a molded product is processed. A mold is formed.

According to a third aspect of the present invention, a method for casting a cast character portion of a gun arm is to form a concave portion by a cutout hole in a shell plate for each layer and to store a character mold. Form a cut-out hole that is possible and integral with the cavity that is easy to accommodate the character mold.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described below with reference to the accompanying drawings.

FIG. 1 is a cutaway view of a main part of a mold used in a method for casting a cast character portion of a gun arm according to the present invention.

A shell mold for gun arm casting is composed of shell plates 1, 2 and 3 corresponding to each layer divided into three layers, a lower plate 4 forming a bottom thereof, and an upper plate (not shown) forming a lid. Become.
A cavity 6 corresponding to the gun arm is formed by these shell plates. Facing the inside of the cavity 6, skirting boards 7, 8 and a character mold 9 for holding the embedded member are provided.

Each shell plate constituting the shell mold is
A shell plate having each thickness (about 5 to 15 mm) is prepared in advance by shell sand, and cutout holes are formed in the shell plate by a water jet machine. At this time, in addition to the cavity part that forms the shape of each layer divided into three layers of the gun arm, a shape that combines the plan parts such as the baseboard part that fixes the embedding member, the character mold part, and the runner (not shown) Make a cutout at

Since the cavity, the character mold part and the like are formed as cut-out holes in the shell plate by easy plane processing, the positional relationship can be defined with high precision. Further, the character mold part can be formed on the lower plate 4.

FIG. 2 is a sectional view taken along line AA of FIG.

The character mold 9 is a single molded body having an uneven character or mark formed on the surface thereof. The character mold 9 projects into the cavity (projection amount B) in a concave portion formed by cutting out the shell plate 2 for each layer. It is fitted. By setting the protrusion amount B to a size exceeding the surface processing cut depth of the molded product, a transfer character pattern is formed at a sunk position which does not disappear even by processing the molded product.

FIG. 3 shows a molding procedure of a character mold. FIGS. 3 (a) to 3 (c) are conceptual diagrams of each step of exposure, development and transfer, and FIG. 3 (d) shows a character mold.

First, the original plate 12 is superimposed on the resin plate 11 shown in FIG. 1A and projected and exposed by an ultraviolet light source 13 so that the resin plate 11 corresponding to the ultraviolet transmitting portion of the original plate 12 is exposed.
Is hardened. As the resin plate 11, a thermosetting gel resin plate having a thickness C corresponding to the height of the engraved character is used. The original plate 12 is drawn on a transparent plate with ultraviolet light shielding ink, and arbitrary characters and marks can be easily manufactured.

Next, when the uncured portion 11b of the resin plate 11 is removed by the solvent 14 shown in FIG. 3B, the exposed cured portion 11a remains, and a resin character pattern which can be used repeatedly within a certain limit is obtained. can get. By transferring this character prototype to the shell sand 15 using the frame 15a in FIG.
A character mold 9 in which the irregularities of a predetermined character height shown in FIG.

The character prototype is advantageous in that it is easy to manufacture and store and does not require a large storage space. In the case where precision transfer is required, fine sand can be used for the character-type portion of the character mold 9, and in this case, the fine character mold 9 is formed at low cost by a small amount of fine sand covering the character prototype 11a. can do.

As described above, according to the method for casting a cast character portion of a gun arm according to the present invention, an exposed portion by character projection is formed by forming a concave and convex character prototype with a hardening resin, and transferred from the concave and convex character prototype to form a character mold. By molding this character mold into a recess formed in the shell plate and performing casting with the closed shell mold, it is possible to cast a gun arm in which any character or the like is individually cast.

[0023]

As described above, the mold used in the method for casting a cast character portion of a gun arm according to the first aspect of the present invention is a laminate of a shell plate, a lower plate, and an upper plate for each layer having cutout holes. In addition, the exposed portion by the character type projection for the character type portion was shaped as a character mold transferred from the concave and convex character prototype remaining formed by the curable resin, and the concave portion was formed in the shell plate and housed. From, a mold is formed without the need for a wooden mold by laminating shell plates,
In addition, an arbitrary cast character based on character-type projection can be formed by a character template that can be individually set and accommodated in the concave portion of the shell plate.

According to a second aspect of the present invention, a mold used in the method of casting a cast character portion of a gun arm projects into a cavity beyond a machining cut depth of a molded product, and the character mold is housed in a concave portion of a shell plate. Therefore, a transferred character can be formed at a sunk position which does not disappear even by processing.

According to a third aspect of the present invention, there is provided a mold for use in a method for casting a cast character portion of a gun arm, wherein a cutout hole is formed in a layered shell plate having a cutout hole in a cavity portion to accommodate the character mold. Therefore, the housing portion of the character mold can be easily processed as a cut-out hole integral with the cavity portion, and the character mold can be easily assembled.

[Brief description of the drawings]

FIG. 1 is a fragmentary cutaway view of a mold used in a method for casting a cast character portion of a gun arm according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a conceptual diagram showing a molding procedure of a character mold.

[Explanation of symbols]

1, 2, 3 ... shell plate, 4 ... lower plate, 5 ... upper plate, 6 ... cavity, 7, 8 ... skirting board, 9 ... character mold, 11 ... resin plate, 11a ... hardened part (concavo-convex character prototype) , 11b: uncured portion, 12: letter master, 13: ultraviolet light source (exposure source), 14
... Solvent, 15 ... Shell sand, 15a ... Frame, B ... Protrusion amount.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-207444 (JP, A) JP-A-54-83627 (JP, A) Full-fledged Sho 59-185042 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) B22C 9/02 B22C 9/22 B22C 13/08 B22D 25/02

Claims (3)

(57) [Claims] 1. A method for casting a gun arm using a shell mold in which a cavity is formed by shell sand and a character portion facing the cavity is formed, wherein the shell mold has a cavity corresponding to a molded product to be cast. A layered shell plate having a cutout hole in a shape obtained by layering, and a lower plate forming the bottom of the cutout hole and an upper plate forming a lid are laminated, and the character-shaped portion is
The exposed portion by the character type projection is formed by forming a concave and convex character prototype with a curable resin, and a character mold is formed by transferring from the concave and convex character prototype, and the character mold is accommodated in the shell plate by forming a concave portion in the shell plate. A method for casting a cast character portion of a gun arm. 2. The method according to claim 1, wherein the character mold protrudes into a cavity beyond a depth of cut when processing a molded product. A method for casting a cast character portion of a gun arm, wherein the character portion is housed in a recess. 3. The method according to claim 1, wherein the character mold is formed by a cutout hole in a shell plate for each layer of a shell mold having a cavity cut out. A method for casting a cast character portion of a gun arm, characterized by forming and containing