JPH0155930B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing twisted blades having any amount of twist, particularly useful for use in implanted or attached cutters.

Twisted blade cutters have less vibration and much superior cutting performance than straight blade cutters, and are therefore widely used in the cutting industry. The blades of these twisted-edged cutters commonly used today include high-speed steel cutters, small-diameter carbide cutters with twisted grooves directly formed on the tool material, and high-speed steel cutters. It is constructed as a blade cutter in which a blade made of speed steel or carbide is fixed to a steel shank such as structural steel by mechanically clamping or brazing.

However, except for small-sized cutters, this type of twisted-blade cutter is expensive, so the above-mentioned barbed cutter is rarely used, and implanted or attached-edge cutters are used exclusively.

These implanted blades and cutters with attached blades require blades as twisted blades made of tool material, but manufacturing such blades is accompanied by many difficulties. In other words, twisted-edged blades made of high-speed steel require many man-hours to machine from the material, have a low yield, and are easily deformed during the heat treatment process, making it difficult to grind them to achieve precision. However, since it is difficult to hold the product, it is difficult to grind, and as a result, it is expensive. on the other hand,
Cemented carbide blades are formed by pressurization with a mold or extrusion before sintering, but these methods have the disadvantage that they are more difficult to manufacture than high-speed steel blades because of the large deformation caused by sintering. . Furthermore, integral blades with strong twists or long twisted edges cannot be molded. Therefore, although there is a strong market demand for cutters that use integrated blades with strong twists or blades with long twisted blades molded in one piece, these demands have not been met, and in reality, the cutters are less than required. Blades with a twist or blades with many short tips fixed along the twist are used.

In view of the current situation, it is an object of the present invention to provide a method for manufacturing a blade with a high-precision integrally twisted edge. It is also possible to provide seamless blades for end mills that are long, for example longer than the length of the lead.

In this application, the sector angle is the angle formed when a straight line connecting the outer periphery of each axis-perpendicular cross section and the axis at both ends of a seamless single blade in the longitudinal direction is projected onto the same axis-perpendicular plane, that is, the axis. The angle between the two ends of the blade when projected on a right-angled cross section. In addition, the helix angle is the angle between the helical winding of the blade and a straight line parallel to the axis of the blade that passes through a point above it when the tool is cylindrical, or when the tool is a conical hollow body. , the angle formed by the conical helical winding of the blade and a straight line parallel to the axis of the blade that passes through a point on it and projected onto a plane perpendicular to the radius of the blade that passes through that point (JIS-B-0101). say.

The present invention will be explained in detail by way of examples.

FIG. 1 shows an example of an apparatus used in the blade manufacturing method of the present invention. In the figure, 1 is a table of a wire cut electrical discharge machine. On this table 1 is a horizontal rotary head 3 having a rotation axis x-x extending in a direction perpendicular to the processing wire 2.
and a support shaft 5 are provided. A hollow member 4 made of a tool material and pre-formed into a predetermined shape, such as a right cylindrical shape or a conical shape, is attached to the horizontal rotating head 3 via a support shaft 5 concentrically with the rotational axis x-x. 4 is fixed to the support shaft 5 by means such as brazing. The equipment cylinder 4 on this rotary support shaft is rotated by a drive motor 6 provided on the rotary head in accordance with a preset control command. table 1
similarly moves in the direction of arrow 7 according to the control command.

By appropriately performing command control, it is possible to easily manufacture a long blade with a fan-shaped angle of any size and a free helix angle, as will be described later.

FIGS. 2 and 2A are examples of a four-blade end mill manufactured by the method of the present invention, in which four blades are brazed. Each blade 4' has an outer diameter D,
It constitutes a tool blade portion having a length l, each having dimensions of a thickness t and a width S.

3 and 3A are schematic views of one blade section taken out from the end mill shown in FIG. 2. When the blade 4' has a diameter D and a helix angle θ, the lead of this blade is L. L=πD/tanθ...(1) Therefore, for a blade of length l, the fan angle β seen from the end face is β=360×l/L=(l・tanθ/πD)×360°.

becomes.

The blade 4' as shown is manufactured by the following method.

In Fig. 1, the tool equipment 4 has a hollow cylindrical shape with a length l, a diameter D, and an inner diameter (D-2S). The relationship between the tool and equipment is such that the machined surface can be made into a twisted surface by moving by L in (1) above for one rotation of the tool and the tooling and equipment 4 making a screw movement relative to the processing wire 2. can. The tool equipment 4 is glued to the support shaft 5, and even if the length of the tool equipment 4 used for the above-mentioned processing is set to a length l' that is somewhat longer than l, the tool is prevented from falling off after processing. There is.

Fig. 4 is a drawing of the tool equipment 4 seen from the end. The machining wire starts machining at the a-a position, and after machining the length l' while making a screw movement along the helix angle, While performing a screw movement in the opposite direction from the position, return to the end face position a-a, then move the processing wire perpendicular to the axis x-x by the required thickness t of the tool equipment, and repeat the same operation from the position a'-a'. Perform processing.

After indexing the x-x axis by an appropriate angle r, repeating this motion as bb, b'-b', c-c, c'-c', etc., the tool equipment 4 and the support shaft are moved. By separating the blades 5, several accurately twisted blades A ₁ , A ₂ , B ₁ , B _{2 .} . . can be manufactured from the same tool equipment 4. It is also possible to attach the tool 4 directly to the horizontal rotary head 3 without using the support shaft 5, and to cut it to the required length after machining. In addition, the thickness of the tool equipment t
corresponds to the blade thickness t in FIG.

FIG. ₅ is _an expanded view _of the tool equipment shown in FIG. ′→b ₁ ′
→
It shows that the process proceeds as b′…. Note that l is the length of the tool 4, l' is the machining length, and t is the thickness of the tool.
Further, the tilt angle θ corresponds to θ in FIG.
In addition, according to this method, A ₁ and A ₂ , B ₁ and B ₂ at the same time
It is also possible to machine a blade with two twists, such as A ₁ and A ₂ are exactly the same if the tool material is a hollow cylinder. However, for blades where the tool material is a hollow cone shape, or where the torsion angle θ changes depending on the axial position of the tool material, the shapes of A ₁ and A ₂ will depend on the position of the machining wire. varies depending on the offset position of the tool from the center. For example, as shown in Figure 4, if a-a passes through the center and a'-a' is deviated from the center by t, then
If the tool equipment has a shape other than a cylinder, the shapes of A ₁ A ₂ will not be the same and only one will have the required shape.
However, as long as the deviation from the center is not particularly large, there is often no problem in using it.

The method of the present invention as detailed above completely eliminates the disadvantages of conventional manufacturing methods such as the deformation factors in manufacturing twisted blades, such as heat treatment in high-speed steel and sintering effects in cemented carbide. Long blades with arbitrary helix angles, blades with unequal leads, and tapered cutter blades with strong sector angles that can not only be removed but cannot be manufactured using conventional mechanical methods. etc. can be manufactured arbitrarily and with high precision simply by changing the control program. For example, the manufacturing range of the sector angle β of the blade in the side view of FIG. 3A was conventionally 120° or less, but according to the method of the present invention, it can be manufactured over 120°, and even the stroke of the electric discharge machine can be tolerated. It is also possible to manufacture objects with angles of 360° or more with high precision.

By using the blade according to the method of the present invention, it is possible to easily manufacture, for example, a long end mill with a strong helix and a tapered die-sinking end mill with a seamless single blade, which could not be manufactured in the past, which brings benefits to the machining industry. The blade is very large, and cutters that are grafted with twisted blades, which were conventionally impossible to perform strong cutting due to the poor precision of the twisted surface, can now be cut with strong force by improving the precision between the back surface of the blade and the mounting surface.

Furthermore, surface defects (for example, minute cracks, etc.) may occur due to electrical discharge machining of cemented carbide, etc.
After attaching the blade to the tool shank, it is common to cut the outer periphery, rake face, etc., and it is easily removed through this process, causing no actual damage.

Although the above specific example describes the case where a wire cut electric discharge machine is used as the blade cutting means, those skilled in the art can easily imagine that the same effect can be obtained by using electron beam machining or laser machining in addition to this. Good morning.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing an embodiment embodying the method of the present invention, Fig. 2 is a side view of an end mill to which a blade manufactured by the method of the present invention is brazed, and Fig. 2A is a schematic front view of Fig. 2. Figure 3 is a side view showing only the blade in Figure 2, Figure 3A is a schematic front view of Figure 3, Figure 4 is an end view of the tool machined by the method of the present invention, and Figure 5. is a developed view of FIG. DESCRIPTION OF SYMBOLS 1... table of electrical discharge machine, 2... electrical discharge machining wire, 3... horizontal axis rotating head, 4... tool equipment, 4'... blade, 5... tool equipment support shaft,
6...Drive motor, β...Sector angle.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a twisted blade from tool equipment, comprising: providing a horizontal rotating head having an axis perpendicular to a machining wire on a table of a wire-cut electrical discharge machine; Installing a hollow tool made of a tool material having a desired shape on the axis of a rotating head; Positioning a machining wire at an end face position of the tool passing through the axis of the hollow tool; Processing wire and tool moving the tool and the tool relative to each other in the axial direction of the tool, creating one surface of the twisted blade while giving a required rotation angle to the horizontal rotating head in response to this movement, and creating a creation end position. returning the processed wire to the end face position by performing a screw movement in the opposite direction from
moving the machining wire and the axis of the tool equipment by a required dimension in a plane perpendicular to the axis;
relatively moving the processing wire and the tool equipment from that position in parallel with the axis of the tool equipment in the axial direction of the tool equipment, while giving the required rotation angle to the horizontal axis rotation head in accordance with this movement; A method for manufacturing a twisted blade comprising the steps of creating the other side of the twisted blade and cutting off the twisted blade from the tool equipment. 2. The method according to claim 1, wherein the tool equipment has a hollow cylindrical shape with a required inner diameter and outer diameter. 3. The method according to claim 1, wherein the tool equipment has a hollow conical shape with a required inner diameter and outer diameter.