CZ306051B6 - Shank-type, monolithic, milling cutter with axial cooling channel - Google Patents

Abstract

The present invention relates to a shank-type, monolithic, milling being provided on its face with cutting edges (1). Peripheral cutting edges (2) and segments of face cutting edges (3) are standard. During rotation, the internal cutting edges (1) form a hollow space around a cooling channel (6). The hollow space enables free forming and removal of the cutting edge (1) chips during plunging operations. The construction of the internal cutting edges (1) is defined by the apex angle 90 degrees +/- 25 degrees starting on the half radius of the milling cutter with tolerance +/- 20 percent and arbitrary depth for the need of the given angle of plunging.

Description

Shank, monolithic, face, cylindrical cutter with axial cooling channel

Field of technology

The invention relates to end mills, monolithic, face, cylindrical milling cutters, in particular in the range of diameters D6 to D32 with a central odor, which are used for removing machined material from closed cavities by the immersion method in a helix or on a ramp. These are operations where, due to the oblique movement in two axes simultaneously, a combined load occurs in two directions, and its overall size limits productivity. The following subject of the patent deals, inter alia, with the reduction of this load.

Prior art

If a so-called closed pocket of various floor plans with corner radii in the range of R3 to R16 is to be excavated in workpieces, a relatively small diameter monolithic cutter with at least one cutting edge on the face extending to the center of the cutter must be used instead of a cutter with replaceable inserts. along an inclined path, the so-called ramp, to the maximum possible depth. The chip area of a given plunging operation is formed by the sum of the chip area of the cutting edges on the entire face area and at the same time the chip area of the cutting edges located on half of the cylindrical surface of the currently plunging cutter. It is actually a sloping groove. This sum of the two surfaces, cylindrical and frontal, is the location of the cutting force vectors, which can be calculated from the area of the chip taken on all cutting edges in contact, multiplied by the specific cutting resistance. The total cutting force, thus the power and especially the productivity is limited by the possibilities of the system. When it is exceeded, all that remains is to reduce the size of both feeds - vertical, horizontal, but at the cost of a shift to the area of even thinner chips at the face with a higher specific cutting resistance, which often worsens the situation. The operation is often characterized by a tendency to vibration. Equally important is the problem of rinsing thin and wide chips from the cutting point on the front surface due to their "bulkiness".

The essence of the invention

The above-mentioned drawbacks are largely eliminated by the shank, monolithic, face, cylindrical milling cutter with axial cooling channel and cutting edges according to the invention. Its essence is that the cutter is provided on its face with a conical cavity formed by cutting edges with an apex angle of 90 ° with a tolerance of ± 25 °. The conical cavity is created by rotating at least one cutting edge. The diameter of the conical cavity at the front of the cutter is equal to the size of half the diameter of the cutter with a tolerance of ± 20%.

On a cutter equipped in this way, the insertion of cutting edges fundamentally changes the load of all cutting edges on the face and the size of the resulting chips, which make it easier to leave the cutting point. Partial reinforcement and chip breakage at the forehead use areas of lower resistivity. Another effect is the creation of an internal space between the cutting edges, where no chips are formed and allows the safe outlet of the pressure medium without the risk of clogging. The plunging angle (ramp) or the helix angle during plunging can be selected to be around 10 °, which is about a twofold increase compared to the current state with the corresponding productivity.

Explanation of drawings

A shank, monolithic, face, cylindrical milling cutter with an axial cooling channel and sharp-edged and toric cutting edges, as possible variants according to the invention, are described in more detail and compared with a standard milling cutter with the aid of the accompanying drawings. 1 is a front elevational view of a standard sharp corner cutter, and FIG. 2 is an enlarged detail of the same cutter when plunging with hatched chip areas. Fig. 3 shows a front view of a milling cutter with cutting edges according to the invention

-1 CZ 306051 B6 sharp-edged and in Fig. 4 the same cutter is captured in enlarged detail again when plunging on a ramp with hatched chip surfaces. For a more comprehensive idea, in addition, Figures 5 and 6 are attached, where Figure 5 shows the cutting edges as the essence of the invention applied to toric cutters, and Figure 6 is an axonometric view of a sharp-edged cutter with cutting edges according to the invention. In Fig. 7, the positions of the affected attributes of the invention are indicated and named. Fig. 8 is a tolerance field of dimensions and positions of these attributes providing the function of the invention.

Examples of embodiments of the invention

Shank, monolithic, face, cylindrical cutter according to Fig. 7 with an axial cooling channel 6 is provided with a conical cavity with an apex angle of 90 ° ± 25 ° during its rotational movement. The conical cavity is formed by rotating cutting edges 1. The diameter of the conical cavity at the cutter face is equal to half the cutter diameter with a tolerance of ± 20%. The main circumferential edges 2 are located around the circumference of the milling cutter, and on the face of the milling cutter there are shortened face edges 3 with a tooth gap 4 of the face. In the core 5 of the cutter there is a channel 6 for the supply of medium.

Industrial applicability

The end, face, cylindrical end mill with axial cooling channel and cutting edges of the present invention can become a standard end mill model with increased versatility. The cutting edges do not affect the original functions such as grooving, shoulder milling or face milling. The invention can be applied to sintered carbide end mills as well as any other cutting material. As for the shape of the cutters, it can be used on sharp-edged, chamfered, toric and shaped cutters. The area of machined materials is the same as with standard milling cutters. Milling various cavities that need to be excavated is a very common operation, eg in the production of molds. The milling cutter according to the invention in a toric design, with corner radii, is also used for 3D milling of shallow shapes. An increase in productivity can be expected in these works.

Claims (1)

PATENT CLAIMS Shank, monolithic, end, cylindrical milling cutter with axial cooling channel, characterized in that it is provided on its face with a conical cavity with an apex angle of 65 ° to 115 ° and an axis identical to the milling cutter axis, provided with at least one cutting edge (1) , the diameter of the conical cavity at the face of the cutter being equal to half the diameter of the cutter with a tolerance of ± 20%.