JP2854431B2 - Method for removing blow marks from shell core - 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 removing a blow mark of a shell core used for removing a blow mark of a core formed in a shell molding.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, a shell core 1 formed in a shell molding has a large number of square blow marks 3, 3,. Since the blow marks 3, 3... Become obstructive during product casting, they are removed after molding.

As a conventional method for removing the blow marks 3, 3,..., As shown in FIG. 4, a blow mark folding bar 4 which moves relatively to the shell core 1 in the lateral direction is used. , So that the blow marks 3, 3,... Are cut off and removed.

[0004]

By the way, in the above-mentioned conventional method, the blow marks 3, 3,... Are removed by being cut off by a blow mark folding bar 4 which moves relatively to the shell core 1 in the lateral direction. As shown in FIG. 5, the root 3a of the blow mark 3 remains in the core body 2 or the core body 2 is cut off by the blow mark 3 and the depression 2a is formed in the core body 2. Can be. When the root 3a of the blow mark 3 remains in the core body 2, the root 3a of the blow mark 3 needs to be cut off as a separate process, and there is a problem that it takes time and effort correspondingly. In the case where the core body 2 is cut off at the blow mark 3, as shown in FIG. 6, the product 5 cast using the shell core 1 is provided with a depression 2 a formed in the core body 2. Since the buildup 5a is formed in a portion corresponding to the above, there has been a quality problem such as a decrease in cooling performance due to the buildup 5a in a water jacket, for example. Incidentally, as shown in Japanese Utility Model Application Laid-Open No. 63-6160, it is also conceivable to cut and remove the blow marks 3, 3,... Of the shell core 1 by using a cutting machine so that the surplus material of the work is cut and removed by the cutting machine. However, the root 3a of the blow mark 3 remains in the core body 2 due to the processing tolerance of the cutting machine, or the core body 2 is shaved off, and the same as the case where the blow mark folding bar 4 cuts the above. There was a problem.

The present invention has been made in view of such conventional problems, and has as its object to solve the above problems.

[0006]

According to the present invention, in order to achieve the above object, a blow mark is formed on a core body of a shell core through a frustum-shaped land formed in a thin wall, and the blow mark is formed. Provided is a method for removing a trace of blow of a shell core, wherein the land is shaved off by a cutting machine capable of moving forward and backward and ascending and descending at the same time.

[0007]

According to the method for removing blow marks of a shell core according to the present invention, a blow mark is formed on a shell core body through a thin frustum-shaped land formed on a core body, and the land is cut by a cutting machine. Since the blow marks are cut and removed at the same time as the chips are cut off, the blow marks do not remain on the core body or the core body is not cut off. Only a very smooth land without any problem remains on the core body.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for removing blow marks from a shell core according to the present invention will be described below with reference to FIGS.

FIG. 1 is a schematic view showing an example of an apparatus for carrying out the method according to the present invention. Reference numeral 11 denotes a shell core set on a jig (not shown) based on a width standard. A predetermined number of blow marks 14 are formed on the upper surface of the main body 12 through a thin-walled, for example, frustum-shaped land 13 formed to about 0.5 mm. Reference numeral 15 denotes a cutting machine for removing a blow mark 14 of the shell core 11, and has a cutter wheel 17 such as a diamond wheel driven by an electric motor 16 for rotation. This cutter wheel 17 is a hydraulic or pneumatic cylinder 18
As shown in FIG. 2, a clearance H smaller than the thickness T of the land 13 or close to the upper surface of the core body 12 of the shell core 11 can be moved by the lifting means (not shown).
It is configured to be able to ascend and descend so as to descend with a tolerance such that

As an operation procedure, first, a shell core is set on a jig (not shown) based on a width rule. next,
As shown in FIG. 2, the cutter wheel 17 of the cutting machine 15 is moved up and down by an unillustrated elevating means, as shown in FIG.
It descends vertically to the gap H smaller than the thickness T of the land 13 in close contact with the upper surface of 12. Next, while rotating the cutter wheel 17 of the cutting machine 15 by the motor 16,
It advances horizontally by cylinder 18 against 11 lands 13. Then, the cutter wheel 17 of the cutting machine 15 cuts off the land 13 of the shell core 11 and cuts and removes the blow mark 14 at the same time.

Thus, according to the present invention, the land 13 of the shell core 11 is shaved off by the cutter wheel 17 of the cutting machine 15 and at the same time the blow mark 14 is cut and removed, as in the conventional method. Part of the blow mark 14 does not remain in the core body 12 and the core body 12 is not removed.

By the way, the cutter wheel 17 of the cutting machine 15
In the case where the blow mark 13 is cut and removed in a state where the cutter wheel 17 is not closely contacted with the upper surface of the core body 12 of the shell core 11 and is lowered with a gap H left due to the processing tolerance of the upper surface of the core body 12, Land 13 slightly remains in the land
Since the frustum 13 is formed in advance into a frustum shape, the remaining portion of the land 13 is very smooth with respect to the upper surface of the core body 12, and it is difficult for sand to remain on the product during casting, so that there is no quality problem.

[0013]

As described above, according to the present invention,
Since a blow mark is formed on the core body of the shell core through a frustum-shaped land formed in a thin wall, and the land is cut off by removing the land with a cutting machine, the blow mark is removed. Thus, there is no longer any part of the blow marks remaining and the core body is not cut off, whereby the effects of reducing man-hours and improving the product quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an apparatus for implementing a method for removing a trace of blow of a shell core according to the present invention.

FIG. 2 is an enlarged view showing details of a portion A in FIG. 1 and a lowered position of a cutter wheel of the cutting machine.

FIG. 3 is a perspective view showing an example of a shell core.

FIG. 4 is an explanatory view showing a conventional method for removing a blow mark of a shell core.

FIG. 5 is an explanatory diagram showing a case where blow marks are removed by a conventional method.

FIG. 6 is a partial cross-sectional view of a product cast using a shell core from which blow marks have been removed by a conventional method.

[Explanation of symbols]

 11 Shell core 12 Core body 13 Land 14 Blow mark 15 Cutting machine 16 Motor 17 Cutter wheel 18 Hydraulic cylinder T Land thickness

Claims (1)

(57) [Claims] 1. A blow mark is formed on a core body of a shell core through a thin frustum-shaped land formed in a thin wall, and the blow mark is scraped off by a cutting machine capable of moving forward and backward and ascending and descending. A method for removing blow marks from a shell core, wherein the method removes and removes the blow at the same time.