JPH0121684Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stepped tool for groove machining that is useful for groove machining such as parting groove machining and trepanning groove machining.

Generally, parting groove machining in lathe machining is performed while applying rotation to the workpiece 1 as shown in Fig. 1.
A parting tool 2 is pressed against the outer periphery of the workpiece 1. The parting tool 2 used here has a shank 2a as shown in Fig. 2a and b.
A chip 2b having a width corresponding to the width to be processed is attached to the tip of the chip. When grooving is performed using such a parting tool 2, the chips 4 are continuously curled into a spiral shape on the rake surface of the chip 2b, as shown in FIG. In this case, each piece of the spiral is wound while shifting its position in the width direction as shown in FIG. 4, so the total width d of the spiral is equal to or larger than the width e of the chips.

For this reason, in the past, the frictional force between the groove side wall and the chips became large, and the chips 4 were tightly wound inside the groove, making it difficult to automatically discharge them. In particular, the workpiece 1 is rotated as shown in FIG.
Press the trepanning tool 3 against the end face of
When trepanning an annular groove, the third
As shown in the figure, the spiral chips 4 strongly contact the side walls of the annular groove, making it extremely difficult to automatically discharge them.
(In addition, in FIG. 3, the chips 4 are shaded for easy identification.) Therefore, in the past, the machine was stopped for a while and the chips 4 were removed manually.
This has been a major obstacle in promoting unmanned processing. Moreover, when machining is performed using high-speed cutting using carbide chips, spiral chips are generated very quickly, making it difficult to stop the machine in time, resulting in damage to the tool or workpiece.

In this way, in conventional groove machining such as parting groove machining and trepanning groove machining, chips with the same width as the groove to be machined are generated and become clogged in the groove, so these chips have to be removed manually. It is.

The object of the present invention is to provide a stepped tool for groove machining that can naturally discharge chips. The structure of the present invention that achieves this purpose includes a first cutting edge having a width corresponding to the groove to be machined, and a second cutting edge having a width narrower than the first cutting edge and protruding from the first cutting edge. It is characterized by having a cutting blade.

Hereinafter, the stepped tool for groove machining of the present invention will be described in detail based on examples.

An embodiment of the present invention is shown in FIGS. 6 to 9. The embodiment shown in the figure is an application of the present invention to a cut-off tool. That is, a tip 11 is attached to the tip of the shank 10, and the tip 11 is formed with a first cutting edge g, a second cutting edge f, and a discharge passage h. The first cutting edge g is an edge portion formed between the front flank face and the rake face of the chip 11, and its width corresponds to the groove to be machined. The second cutting edge f protrudes from the lower half of the front flank of the chip 11, and its width is equal to that of the first cutting edge g.
It is narrower than that of . Furthermore, the protruding position of the second cutting edge f is located approximately at the center of the front flank surface, and a hollow-shaped discharge passage h is formed on both left and right sides thereof so that chips can be easily discharged. Furthermore, the second
Although the cutting edge f is exaggeratedly drawn in the drawing, its protrusion amount may actually be about 0.2 to 0.5 mm.

When the parting tool of the present invention having the above configuration is used, chips are discharged as follows.

That is, as shown in FIG. 10, when the parting tool of the present invention is pressed against the circumferential surface of the rotating workpiece 12, the second cutting edge f, which protrudes more than the first cutting edge g, cuts around the circumference of the workpiece 12. It first contacts the surface and creates a narrow chip dividing groove i.
is cut first. At this time, the chips j are generated by being shredded in a spiral shape, and are discharged through the left and right discharge passages h. As the cutting continues, the first cutting edge g comes into contact with the uncut portion k separated left and right by the chip dividing groove i, and the planned groove is formed around the circumference of the workpiece 12 as shown in FIG. Cut into a surface. At this time, the chips 1 are divided into two thin strips, which slide separately on the rake face of the chip 11 and are naturally discharged from the groove.

In this way, in the present invention, since the second cutting edge f is provided which is narrower than the first cutting edge g and protrudes more than the first cutting edge g, the chips l are divided into two thin strips.
It drains naturally and does not get clogged in the groove. Therefore, the effort of manually discharging the chips becomes unnecessary, and unmanned cutting can be promoted. Furthermore, even in high-speed machining where chips are generated very quickly, the chips are quickly discharged, which prevents damage to the tool, workpiece, and machine due to chip clogging. Furthermore, since a gap is created between the cutting edge and the chips, there is an advantage that the circulation of cutting fluid is improved and the life of the cutting edge is extended.

In addition, in the above embodiment, since there is a vertical step between the first cutting edge g and the second cutting edge f, the generation positions of the chips j and the chips l are different, and the chips l can be reliably separated. Natural discharge can be ensured.

Further, in the present invention, the second cutting edge is not single as in the above embodiment, but may be plural, and the second cutting edge may be a plurality of pieces.
may be divided into two or more.

As described above in detail based on the embodiments, the stepped tool for groove machining of the present invention can naturally discharge chips from the groove, so there is no need to manually discharge chips. It also has the practical advantage of being easy to manufacture due to its simple structure. The present invention is not limited to the parting tool of the above embodiment, but can be widely applied to tools for groove machining such as turning, boring, and boring groove machining.

[Brief explanation of drawings]

Figures 1 to 5 relate to conventional groove machining tools.
Fig. 1 is an explanatory diagram showing the mode of grooving, Fig. 2a is a perspective view of the parting tool, Fig. 2b is a perspective view of the chip, Fig. 3 is an end view showing the state of trepanning grooving; Figure 4 is a perspective view of spiral chips, Figure 5 is a side view showing how chips are formed in a spiral shape, and Figure 6 is a side view showing how chips are formed in a spiral shape.
- Figures 11 relate to an embodiment of the stepped tool for groove machining of the present invention, Figure 6 is its side view, Figure 7 is its front view, Figure 8 is its top view, and Figure 9 is its A perspective view of the chip, FIG. 10 is an explanatory diagram of the step of cutting the chip dividing groove i in advance, and FIG. 11 is an explanatory diagram of how the chips are divided and generated. In the drawing, 1 and 12 are workpieces, 2 is a parting tool, 2a and 10 are shank, 2b and 11 are chips, 3 is a trepanning tool, 4 is a chip, f
is the second cutting edge, g is the first cutting edge, h is the discharge passage, i
is the chip dividing groove, j is the chip, k is the uncut part, l
is a divided chip.

Claims (1)

[Scope of utility model registration request] A groove characterized by comprising a first cutting edge having a width corresponding to the groove to be machined, and a second cutting edge having a width narrower than the first cutting edge and protruding more than the first cutting edge. Stepped tool for processing.