JPH04152009A - Drill having chamfering edge - Google Patents

Abstract

PURPOSE:To save the chamfering work of burr after drilling by using a drill in which a chamfering edge has been formed in the rear portion behind a prescribed distance from the end part where cutting action is performed, when a hole is drilled in a metallic part or the like for connecting a hose. CONSTITUTION:A drill 10 is made up of a drill body 12 and a shank. The end part 16 where cutting action is performed when a hole is drilled is made up of a cutting edge 18, a flank 20, or the like. In the portion behind a prescribed distance from the end part 16, a chamfering edge 22 is formed. The chamfering edge 22 is formed by cutting off a part of the spiral projection (heel and body clearance) of the drill body 12, and the edge is extended straightly or obliquely while being curved to the axis of the drill. After the end of the drill 10 has passed through the unfinished part of the hole of a work, the drill 10 is shifted by a minute distance in the direction perpendicular to the axis, and while circulating the drill around the axis of the hole 26, or while turning a work around the axis of the hole 26 to the drill 10, the drill 10 is moved backward, so that the chamfering of a groove 34 can be performed by the chamfering edge 22.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) This invention relates to a drill used for drilling holes in a workpiece.

(Background of the Invention) As shown in FIG. 4, there is a metal fitting part for connecting a hose that has a ring-shaped part 100 and a tubular part 102. The manufacturing process of this metal fitting part 103 includes a process of forming an annular groove 104 having a curved bottom surface on the inner peripheral side of the widthwise middle part of the ring-shaped part 100, and a process of forming a hole 104 having a circular cross section.
6 and forming the tubular portion 102.

After forming the groove 104, cutting is performed from the middle lower side to the upper side using a predetermined drill (FIG. 4 CB), and when forming the hole 106, the final end of the hole 106, that is, It is inevitable that burrs 108 will occur at the boundary between the hole 106 and the groove 104.

Conventionally, an operator picks up each metal fitting part 103 one by one, inspects the occurrence of burrs 108, and then manually shaves off the burrs 108 using a predetermined tool.

However, such work is inefficient and requires one person and many work steps, which increases the manufacturing cost of the metal fittings.

For drilling with the above-mentioned drill, the drill is fixed on the tool post, and the unprocessed metal part is held on the spindle side and moved forward while rotating.

This can be done by inserting a drill into the tubular part, but in this case, a special tool with a single chamfer blade is attached to the tool rest alongside the drill, and after drilling the hole with the drill, It is also possible to use a method in which the metal part is moved forward again, an adjacent special field tool is inserted into the hole, and the chamfered edge is used to scrape off the burrs generated.

According to this method, there is no need for manual finishing work by the operator. However, with this method, it is necessary to drill a hole with a drill, then remove the drill from the hole, then insert a special tool into the hole to perform processing, and then remove it. , One-cycle drilling involves a large number of steps and operations, resulting in a long cycle time.

(Means for Solving the Problems) The drill of the present invention has been devised to solve the above problems, and the gist thereof is to drill a hole at a predetermined distance behind the tip that performs the substantial cutting action when drilling a hole. The reason is that a chamfered edge is formed in the part so that the cutting edge extends rearward from the tip of the drill as it advances from the outer circumferential part of the drill toward the finer side.

(Actions and Effects of the Invention) When using the do 2 nord of the present invention, chamfering can be performed almost simultaneously with drilling. That is, first, a drill is inserted into the workpiece while rotating relative to the workpiece to perform cutting, and a predetermined hole is drilled in the workpiece.When the drill penetrates a predetermined location in the workpiece, the hole is drilled. Paris occurs at the final end of . Next, the drill that has penetrated the machined area is moved (eccentrically) slightly perpendicular to the axis of rotation, that is, the axis of the hole, and then the drill is rotated around the axis of the hole in that state. When the drill is moved relatively backward while making a circular motion or rotating the workpiece itself, the chamfered blade formed a predetermined distance behind the tip of the drill hits the area where the crack is generated and scrapes it off. , chamfer the final end of the hole.

As described above, by using the drill of the present invention, it is possible to drill and deburr a hole in a workpiece with a single plunging operation. Therefore, there is no need for a dedicated process for deburring manually as in the past, and even when machining using an NC lathe, the drilling work is simplified.
Cycle time is also shortened.

(Example) Next, embodiments of the present invention will be described in detail based on the drawings.

In FIG. 2, reference numeral 10 denotes a drill, which consists of a drill body (pode) 12 and a shank 14.

Reference numeral 16 denotes a tip portion that performs a substantial cutting action when drilling a hole, and is composed of a cutting edge 18, a flank 20, and the like.

A chamfering blade 22 is located at a predetermined distance behind the tip 16.
The zero-chamfered edge 22 in which is formed here is formed by cutting out a part of the spiral protrusion (heel and second bevel) of the drill body 12, as shown in (B). The cutting edge extends straight or curved obliquely with respect to the drill axis.

FIG. 3 shows a procedure for drilling and chamfering a metal fitting component 28 similar to that shown in FIG. 4, for example, using the drill 10 of this example. To explain this in detail, first, as shown in (A), a large diameter hole 24 is pre-drilled.
(For example, 8g + mφ) Insert the tip side of the trill lO, push it further to cut the unprocessed part, and drill a small diameter (for example, 5mmφ) hole, and as shown in Figures 1 and 3. As shown in (B), once the tip of the drill 10 has penetrated the unprocessed area, first shift the drill 1o by a small distance in the direction perpendicular to the axis (Figure (C)), and then insert the drill 1o into the small diameter hole 26. The drill 1o is slowly retreated while making a circular movement around the axis or while rotating the metal part 28 with respect to the drill 10 around the axis of the hole 26. Then, in the middle, the chamfering blade 22 hits the opening edge of the hole 26 toward the groove 34, and chamfers the edge as the metal part 28 and the trill 10 rotate relative to each other. At this time, the glands that had developed on the same edge are removed at the same time.

After chamfering the edge of the hole 26 in this way,
Next, the trill lO is returned in the direction perpendicular to the axis to a position where the axial center of the drill 10 coincides with the axial center of the hole 26, and then the drill lO is pulled out backward along the hole 26. One cycle of machining the hole 26 is completed at 0 or more. .

As described above, if the drill 10 of this example is used, drilling and chamfering or chamfering can be performed by one thrusting and pulling out of the drill 10 into the workpiece.

Therefore, hole drilling can be performed in a short cycle time.

Although the embodiments of the present invention have been described above in detail, these are merely illustrative, and the present invention has applications other than those described above.

It can also be applied to hole-drilling workpieces made of different shapes, and it can also be applied to hole-drilling workpieces made of not only metal but also resin and other materials, within the scope of the invention. , it can be configured with various modifications based on the knowledge of those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is an enlarged view of the main parts of a drill which is an embodiment of the present invention, FIG. 2 is a diagram showing the overall configuration of the drill, FIG.
The figure is an explanatory diagram of the operation of the same drill, and FIG. 4 is an explanatory diagram for explaining the background of the present invention. Nitrile dual end 22 double chamfered blade

Claims (1)

[Claims] A chamfered edge is formed at a predetermined distance rearward from the tip that performs the substantial cutting action when drilling a hole, and the cutting edge extends rearward from the drill tip as it advances from the outer circumference of the drill toward the axis. A drill featuring