JPH0514018Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is based on a vanishing model casting method in which a vanishing material such as foamed polystyrene is embedded in dry sand and vaporized and vanishes when molten metal is injected. This invention relates to a disc brake cylinder formed as a model.

[Prior art]

The vanishing model casting method can be carried out at a lower cost than the conventional green sand casting method that uses a core, and disc brake cylinders have also come to be manufactured from raw material by the vanishing model casting method.

However, in the vanishing model casting method, a model made of vanishing material such as expanded polystyrene is molded into the same shape as the product (crude material for the cylinder), and when manufacturing the cylinder model, a cup-shaped A method is adopted in which the cylinder part, the bridge part and the reaction part extending from the cylinder part are separately molded using an upper mold and a lower mold, and then these parts are bonded together.

[Problem that the invention attempts to solve]

However, in the cylinder model manufactured as described above, there are problems such as a decrease in the strength of the bonding surface, bonding cost, and ensuring dimensional accuracy.

[Means for solving problems]

The present invention was made in order to solve the above-mentioned problem, and a model of the cylinder made of a vanishing material such as expanded polystyrene is shaped into a cup by using an upper mold, a lower mold, and a movable mold assembled to the lower mold. integrally formed by a cylinder portion having a boot groove formed in the lower half on the opening side by the movable mold, and a lower mold capable of storing the upper mold and the movable mold in the upper part of the cylinder portion on the opening side. a bridge part formed in the cylinder part and extending a predetermined amount in the axial direction of the cylinder part, and a reaction part integrally formed at the tip of the bridge part by an upper mold and a lower mold and extending downward so as to face the opening of the cylinder part. The feature is that the structure has a section.

[Function and effect of the idea]

In the present invention, the cup-shaped cylinder part in the cylinder model is formed by a movable mold that can be stored in the lower mold forming the bridge part, and an upper mold and a lower mold. and the reaction section can be integrally formed, and all of the problems of the prior art described above can be solved.

In addition, in the present invention, since a boot groove is formed in the lower half of the opening side of the cylinder part in the cylinder model, a small amount of molten metal is used when manufacturing cylinder rough material by the disappearance model casting method using this model. It is possible to reduce the weight of the cylinder raw material produced and to reduce the amount of machining performed on the cylinder raw material, and to reduce costs.

〔Example〕

An embodiment of the present invention will be described below based on the drawings.

FIG. 1 shows a model 10 of a cylinder according to the present invention made of a disappearing material such as expanded polystyrene (hereinafter simply referred to as a cylinder model), an upper mold (indicated by a two-dot chain line) 21 used to form the cylinder, A lower die (indicated by a dashed line) 22 and a movable die (indicated by a broken line) 23 are schematically shown. As shown in FIGS. 1 to 5, the cylinder model 10 includes a cup-shaped cylinder portion 11, a bridge portion 12, a reaction portion 13, and a pair of arm portions 14, 15.
The sprue and riser (not shown) are also integrally formed.

As shown in FIG. 1, the cylinder part 11 is
The movable mold 23 is formed into a cup shape by an upper mold 21, a lower mold 22, and a movable mold 23 assembled to the lower mold 22 so as to be movable left and right, and has an inner hole 11a formed at the lower side of the opening at the right end in the figure. The arc-shaped boot groove 11b
is also formed. The outer diameter 11b1 of the boot groove 11b is equal to the inner diameter 3 of the outer wall surface 31 of the boot groove in the cast cylinder 30 after machining shown in FIG.
1a, and its inner wall surface 11b2 is formed to be located slightly deeper than the boot groove inner wall surface 32 of the casting cylinder 30 described above, so that the amount of machining performed on the casting cylinder rough material is It is designed to be less.

The bridge part 12 has a lower mold 22 that can accommodate an upper mold 21 and a movable mold 23 at the upper part of the opening side of the cylinder part 11.
The cylinder part 1 is integrally formed by
1 in the axial direction (right side in the figure) by a predetermined amount (the amount by which the movable mold 23 can retreat from the inner hole 11a of the cylinder portion 11).
It is extending. The reaction part 13 is integrally formed at the tip of the bridge part 12 by an upper mold 21 and a lower mold 22, and extends downward so as to face the opening of the cylinder part 11. One arm 14
An upper mold 21 and a lower mold 22 are placed on one side of the cylinder part 11.
and a second movable mold (not shown) which is attached to the lower mold 22 so as to be movable left and right like the movable mold 23, and the other arm 15 is
It is integrally formed on the other side of the cylinder part 11 by an upper mold 21, a lower mold 22, and a third movable mold (not shown) which is attached to the lower mold 22 so as to be movable left and right like the movable mold 23. There is.

In the cylinder model 10 configured as described above, the cup-shaped cylinder part 11 is housed in the movable mold 23 that can be stored in the lower mold 22 that forms the bridge part 12.
Since the cylinder part 11, the bridge part 12, the reaction part 13, etc. can be formed integrally with the upper mold 21 and the lower mold 22, all the problems of the prior art described in the introduction can be solved. It can be solved.

Moreover, the cylinder model 10 configured as described above
Since the boot groove 11b is formed on the opening side of the cylinder part 11, the amount of molten metal used can be reduced when cylinder rough material is manufactured by the disappearance model casting method using this model, and the manufactured cylinder rough material can be made lighter. It is possible to reduce the amount of machining performed on the raw material of the cylinder, and to reduce costs.

Furthermore, the cylinder model 10 configured as described above
In this case, the outer diameter 11b1 and the inner wall surface 11b2 of the boot groove 11b are set as described above so that the amount of machining performed on the cast cylinder rough material is reduced, so that cost reduction can also be achieved. .

[Brief explanation of the drawing]

Fig. 1 is a central vertical sectional side view schematically showing the cylinder according to the present invention and the upper mold, lower mold and movable mold used to form the same, Fig. 2 is a front view of the cylinder according to the present invention, and Fig. 3 4 is the same side view, FIG. 4 is the same plan view, FIG. 5 is a longitudinal sectional front view taken along the line - in FIG. 3, and FIG. 6 is a central longitudinal sectional side view showing the casting cylinder after machining. Explanation of symbols, 10... Cylinder model, 11...
Cylinder part, 11b...Boot groove, 12...Bridge part, 13...Reaction part, 21...Upper die, 22...Lower die, 23...Movement die, 30...Casting cylinder.

Claims (1)

[Scope of utility model registration request] In the vanishing model casting method, this is a model made of vanishing material such as foamed polystyrene that is embedded in dry sand and vaporized and vanishes when molten metal is injected. A cylinder part formed into a cup shape by a mold and having a boot groove formed by the movable mold in the lower half of the opening side, and a lower part in which an upper mold and the movable mold can be stored in the upper part of the cylinder part on the opening side. a bridge portion integrally formed by a mold and extending a predetermined amount in the axial direction of the cylinder portion; and a bridge portion integrally formed at the tip of the bridge portion by an upper mold and a lower mold and facing the opening of the cylinder portion. A disc brake cylinder is equipped with a reaction part that extends downward.