JPH05138448A - Manufacture of drill with oil holes - Google Patents

Abstract

PURPOSE:To manufacture a drill with oil holes, which has a random helix angle of thread, easily and independently from the material thereof. CONSTITUTION:A casting mold 3, in which cores 2C, 2C for eliminating the mixture slip of the material powder and the binder are inserted, is casted to form a molding, and the cores 2C, 2C are eliminated from the molding to form oil holes 2.

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 drill having oil holes.

[0002]

2. Description of the Related Art A drill (1) having an oil hole (2, 2) as shown in FIG. 2 cools and lubricates the cutting edge by supplying cutting oil to the cutting edge through the oil hole. It is especially useful for cutting difficult-to-cut materials, high speed cutting, deep hole cutting, etc.

Conventionally, in order to manufacture a drill having such an oil hole, a precursor (1A) having two linear through holes (2A, 2A) is prepared by extrusion as shown in FIG. After the precursor (1A) is sintered, it is hot twisted into the shape shown in FIG. 2, and the billet is made by embedding rolling or forging a dissimilar metal material having a different thermal expansion coefficient.
To prepare a precursor (1B) in which the two different metal materials (2B, 2B) are embedded, and cool the precursor (1B)
A method of extracting (2B, 2B), forming a through hole, and hot twisting it into the shape shown in FIG. 2 has been considered.

[0004]

However, the above-mentioned conventional method requires twisting, and it is difficult to apply the conventional method to a material that is difficult to twist, and the twist angle is limited. It cannot be applied to materials such as powder HSS and ceramics that cannot be twisted.

[0005]

As a means for solving the above-mentioned conventional problems, the present invention casts a mixed slip of a material powder and a binder into a casting mold (3) to form the molded product. When manufacturing a drill (1) with an oil hole by firing, a removable core (2C) made in the shape of an oil hole was inserted into the casting mold (3), and the core was formed after molding. A method for producing a drill (1) having an oil hole for removing (2C) from a molded product.

In the present invention, as a raw material, super steel, hard particle-dispersed powder HSS, ceramics, etc. can be used,
As the binder, synthetic resin such as urethane resin, acrylic resin and epoxy resin is used.

The above binder is usually added to the powder of the above material in an amount of 1 to
Mix about 5% by weight and add a solvent to this to make a slip with a solid content of 80-90% by weight, and insert a core (2C, 2C) into the cavity (3A) as shown in Fig. 1. The molded body is prepared by casting the slip in a mold (3).

The core (2C, 2C) used in this case is made in the shape of an oil hole and is removable from the molded body, and has a melting point lower than the softening point of the binder, such as wax or paraffin. , A synthetic resin having a melting point lower than the softening point of the binder, a material soluble in a solvent that does not dissolve the binder, such as ice, for example, a water-soluble synthetic resin when the binder is a water-insoluble synthetic resin, a hexane-insoluble synthetic resin In the case of, a hexane-soluble synthetic resin or wax, a sublimable solid material such as camphor, dry ice, etc. are exemplified.

After forming the molded body, the cores (2C, 2C) are removed by an appropriate means to form oil holes in the traces, and then the molded body is sintered to form oil holes as shown in FIG. Manufacture the drill (1).

[0010]

In the present invention, since the molded product is formed by casting, the desired twist angle can be set regardless of the type of material, and the twist angle can be changed in the middle of the molded product. Then, if the core is removed from the molded body by an appropriate means, an oil hole is formed in the trace.

[0011]

EXAMPLE 3% by weight of a water-curable acrylic resin as a binder was added to super steel powder, and toluene was added to form a slip having a solid content of 85% by weight. On the other hand, in the cavity (3A) of the casting mold (3) shown in Fig. 1, insert two cores (2C, 2C) made in the shape of a spiral oil hole made of wax with a melting point of 60 ° C. Cast the above slip, and further fill port (3B)
A molded body is prepared by spraying water from the above to cure the binder.

The molded body thus prepared is heated to 80 ° C.
The core (2C, 2C) is melted and removed by heating to form an oil hole in the trace, and firing is performed at 1200 ° C for 1 hour.

In this way, the oil holes (2,
A drill (1) with 2) is manufactured.

In this embodiment, hexane may be used to dissolve the core (2C, 2C) in order to remove the core (2C, 2C).

[0015]

According to the present invention, therefore, regardless of the type of material, a drill with an oil hole is easily manufactured, precision machining is easy, and the twist angle can be set arbitrarily, and the twist angle changes in the middle of the drill. Even the thing can be manufactured, and since there is no deformation due to processing, the diameter of the oil hole can be increased.

[0016]

[Brief description of drawings]

FIG. 1 is a sectional view of a mold according to an embodiment of the present invention.

FIG. 2 is a perspective view of a drill with an oil hole.

FIG. 3 is a perspective view of a conventional example.

FIG. 4 is a perspective view of another conventional example.

[Explanation of symbols]

 1 Drill with oil hole 2 Oil hole 2C core 3 Casting mold 3A Cavity

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[Procedure amendment]

[Submission date] July 10, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Delete

Claims (1)

[Claims] Claim: What is claimed is: 1. When a mixed slip of a material powder and a binder is cast in a casting mold to be molded, and the molded product is fired to manufacture a drill with an oil hole, an oil hole shape is formed in the casting mold. A method for manufacturing a drill with an oil hole, characterized in that the removable core produced in step 1 is inserted, and the core is removed from the molded product after molding.