JPH0740122A - Lathing processor - Google Patents

Abstract

PURPOSE:To enable a hardened steel material to be lathing processed under a low cutting speed by arranging a rotary cutter driven and rotated by a motor on the body held on a edge stand and cutting the peripheral surface of a material to be cut by the rotary cutter. CONSTITUTION:A pulley 13 fitted to the shaft 12 of a gear 14 for increasing speed through a power transmission belt 11 is rotated by a pulley 10 fitted to the shaft 8 of a drive motor 7. A driven gear 17 fitted to the shank part 16 of a steel body 15 of a rotary cutter 22 is rotated by the gear 14 for increasing speed. The rotary cutter 22 in which a cylindrical super hard alloy chip 23 forming a peripheral cutting edge 24 and a side edge 25 fitted to an edge stand part 18 formed on one end of a body 15 is integrated fixingly into a screw hole 19 by a screw 21 through a holding metal fitting 20 is rotated. Thereby, a cutting process is carried out by bringing a cutting edge 24 into contact with the surface of a material 26 to be cut.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a turning apparatus for cutting a surface of a ferrous material such as cast iron or alloy steel or a non-ferrous material known as "lathe" while turning the surface.

[0002]

2. Description of the Related Art A headstock equipped with a rotary chuck for holding a work material on a steel frame called a bed, which serves as a base, and a center device for pressing the work material toward the headstock. , And a lathe as a device for holding a blade while reciprocating along the slidable rail on the bed, bringing the blade into contact with the outer surface of the work material, and performing cutting while turning the work material, etc. "Turning machine" is widely used. Usually, the blades of these turning devices are made of cemented carbide, cermet, CB on the tip of a steel square bar called a bite.
A cutting tool of a throwaway tip type in which a tip such as N (cubic boron nitride) is fixed with a screw is used.

As shown in FIG. 3, the conventional turning apparatus has a drive motor and a speed change gear on a bed (50) which is a steel frame having a width of about 5 m and a depth of about 1 m. A headstock (51) with a built-in device is provided, and this headstock (5
1) Scroll chuck (5
Using the center device (55) held by the tailstock (54) installed at the position opposite to the scroll chuck (52), the scroll chuck (5) is mounted on the scroll chuck (5).
The work material (56) is held by inserting the claw (53) of 2) and the center device (55) into the center hole (57) formed in the end surface of the work material (56).

In such a state, the scroll chuck (5
Rotate 2) at high speed, and attach the throw away tip (61) fixed to the cutting tool (60) to the tool rest (59) that reciprocates left and right on the rail (58) to the outer periphery of the work material (56). The cutting edge portion having a small radius of curvature (approximately 0.4 to 1.0 mm) provided at the corner of the throwaway tip (61) is brought into contact with the surface of the work material (56) little by little (0 per rotation). 0.01 to 0.3 mm) Mechanically scraped.

In the case of such a turning apparatus, since the cutting tool is only non-rotatably held on the tool rest,
For efficient cutting, it is necessary to rotate the work material at a high speed to increase the feed rate. Normal work material (5
The peripheral speed of 6) is 50 to 150 m for ordinary alloy steel (rotation speed of 530 to 1600 rpm for a round bar with a diameter of 3 cm) and 150 to 300 m for high hardness steel (rotation speed of 1600 to 3200 rpm for a round bar of a diameter of 3 cm). Becomes

[0006] With such a conventional turning apparatus, it is easy to turn a soft raw steel material, but it is extremely difficult to turn a hardened steel material having a Rockwell (HRc) of 60 or higher. In the case of hardened steel, TiN (titanium nitride) and TiA are added to ordinary cemented carbide chips.
A slow away chip formed with a reinforced coating layer such as 1N (titanium aluminum nitride) has fast wear and is not practical. For this reason, a CBN (cubic boron nitride) or diamond tip fixed to a cutting tool with silver brazing may be used, but it has not yet achieved sufficient cutting performance and is very expensive. It lacks versatility.

For this reason, the turning of the hardened steel material is not a cutting operation but a grinding method using a CBN grindstone (Borazon), which is a usual method. However, in the polishing process, the cutting allowance is several microns per rotation, and it takes a long time for the process, so that there is a problem that the efficiency is extremely low.

On the other hand, as end mills used in milling machines, high-performance products capable of easily cutting high-hardness steel materials have been put into practical use in recent years. Developed by the present inventors 1993
The end mill called "Tornado End Mill", which has been sold since the beginning of the year, has an excellent performance of easily cutting hardened steel materials up to HRc68 at ultra-low speed of 15 m / min. This end mill has a structure in which a TiN (titanium nitride) reinforced coating layer is simply formed on an ordinary cemented carbide chip, but it is characterized by a good blade shape and sharp cutting edge. Outstanding performance and long life even when used for ordinary raw steel,
It is spreading rapidly.

[0009]

SUMMARY OF THE INVENTION According to the present invention, it is possible to easily turn a hardened steel material, which cannot be done by the conventional turning apparatus described above, and to perform turning at a high speed (high speed) by a bite method. Eliminate the waste of energy and expensive high-performance turning equipment brought by the current technology orientation as much as possible, and at the same time, it is easy without using rare materials such as CBN (cubic boron nitride) and diamond. A highly versatile and inexpensive turning device capable of turning hardened steel.

Another object of the present invention is to apply the present invention to a conventional lathe which can only rotate at low speed and to remodel it into a new turning apparatus capable of turning high hardness steel. In addition, the inefficiency of high-hardness steel materials, which was conventionally achieved with a grinder, is replaced with short-time machining by cutting, aiming to greatly improve machining efficiency.

[0011]

DISCLOSURE OF THE INVENTION The present invention has a twisting blade similar to an end mill equipped with a drive motor, instead of a cutting tool of a throwaway tip type for a cutting tool attached to a tool rest of a conventional turning apparatus. The above problem was solved by using a rotary cutter, and by turning the surface of the work material with a twisted cutting edge, rather than hitting one point, the surface can be turned in a short time. . The tool post of the turning device holds a box-shaped body equipped with a drive hydraulic motor and a rotary cutter, and while rotating the rotary cutter with a gear device that transmits the rotational force of the drive motor, the cutting edge is It is characterized in that it abuts the surface of the work material and cuts the work material with a width within the range of the blade length of the cutter.

The rotary cutter may have a blade structure, but preferably, a cylindrical cemented carbide tip is detachably fixed to a blade base portion formed on a body that also serves as a shaft, so that various types of cemented carbide tips can be obtained. The size and shape of the work piece can be used, and the work piece is formed so as to facilitate machining that matches the shape of the outer circumference of the work material. The cemented carbide tip of the rotary cutter is provided with a side blade so that the side surface of the stepped portion formed on the work material can be cut. Further, the rotary cutter can be held while being inclined with respect to the work material, and the work material can be processed into a conical shape.

Since the rotary cutter can increase the cutting speed by rotating itself, it is easy to obtain a required cutting speed, and it is not necessary to rotate the work material having a large weight and a large rotary inertia at a high speed. . Therefore, since it is not necessary to form the headstock part of the turning device for high speed, it is not necessary to increase the capacity of the motor or the brake. In addition, accessories such as inverters to obtain high speed can be small in capacity. If the rotation direction of the outer circumference of the work material is opposite to the rotation direction of the outer circumference of the rotary cutter, the cutting speed will be the sum of both peripheral speeds (relative peripheral speed), so both rotations can be performed at any low speed. It can be adjusted to.

As described above, if the rotary cutter is shaped to have a strong cutting edge that is twisted like the cutting edge of a "tornado end mill", the cutting speed will be high even for hardened steel materials that have been hardened to exceed HRc60. It becomes possible to perform cutting at a low speed of 10 m / min to 100 m / min even at a high speed, and it becomes unnecessary to increase the performance and rigidity of the machine.

Since the body of the apparatus of the present invention equipped with the rotary cutter and the drive motor is formed on the tool rest so that it can be attached and detached, this portion is also attached to the conventional lathe to be modified into a new apparatus. Therefore, turning of high hardness steel material is possible without separately procuring a high-performance turning device. Also, the motor used to drive the rotary cutter is hydraulic, and is formed so that it can obtain high torque with a small size, but this may be one that uses a general-purpose ordinary hydraulic pump and motor, It can be equipped at low cost.

The cemented carbide tip used in the rotary cutter used in the apparatus of the present invention is not particularly limited, and an alloy prepared by appropriately mixing widely used metal carbide powder and metal powder, for example, , W (tungsten)
Of 70% or more is a WC-Co system, a WC-TiC-Co system, or a WC-TiC-TaC-Co system. Alternatively, cermet may be used.

Forming a superhard reinforcing coating layer of titanium, boron, diamond or the like on the surface of the cemented carbide chip having the outer peripheral cutting edge and the side edge, and subjecting the work material having higher hardness to turning. Can be done. That is, PVD (Physical Vapor Deposition), C
VD (chemical vapor deposition), IVD (ion implantation deposition),
By a method such as ion plating, TiN (titanium nitride), TiC (titanium carbide), SiC
(Silicon Carbide), CBN (Cubic Boron Nitride), TiCN (Titanium Carbonitride), T
By forming a reinforced coating layer of iAlN (titanium aluminum nitride), diamond, etc., it is possible to improve wear resistance and chipping resistance (blade spill resistance) during turning of a high hardness work material. .

[0018]

Since the turning apparatus of the present invention has the above-mentioned structure, it is not necessary to rotate the work material at a high speed.
By periodically changing the distance between the work material and the rotary cutter, it becomes possible to form the outer circumference of the work material in a non-cylindrical irregular cross section. In other words, parts such as eccentric cams and crankshafts can be turned after quenching, and since conventional raw steel materials are processed and distortion is removed after quenching, the complex process of finishing with a grinder is required. It becomes possible to rationalize only to cutting.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An explanation will be given below with reference to the drawings showing one embodiment of the present invention. FIG. 1 is assembled into a box-shaped body held by a tool rest of a turning apparatus of the present invention. FIG. 4 is a partial plan view showing a rotary cutter, a drive motor, and a belt drive device that is a power transmission mechanism and a gear device.
FIG. 2 is a left side view of the above FIG. As shown in FIG. 1, the cutting part of the turning device (1) of the present invention is such that a tool rest (2) of a device such as a lathe holds a base part (4) of a box-shaped body (3). , A hydraulic drive motor (7) fixed by a fixing bolt (9) inside the body (3), and a pulley (10) fitted to the shaft (8) of the drive motor (7) The pulley (13) fitted to the shaft (12) of the speed increasing gear (14) is rotated via the power transmission belt (11). The speed increasing gear (14) is a steel body (15) of the rotary cutter (22) of the present invention.
Driven gear (1) fitted to the shank (16) of the
Cylindrical carbide having outer peripheral cutting edge (24) and side blade (25) formed by rotating 7) and fitting into a blade rest (18) formed at one end of body (15) The alloy tip (23) is fixed to the screw hole (19) by the screw (21) through the metal fitting (20) and integrated to rotate the rotary cutter (22), and the cutting edge (24). Is brought into contact with the surface of the work material (26) to perform cutting.

The shaft (12) of the speed increasing gear (14) and the body (15) of the rotary cutter (22) are bearings (27) and (28) and bearings (29) and (30), respectively.
It is supported by. The fitting surface of the cemented carbide tip (23) of the rotary cutter (22) and the blade base portion (18) is formed in an elliptical cross section or provided with an appropriate key groove so as to be non-rotatably fixed.

The skeleton body (3) is provided with walls (5) and (6) on its side surface so that the cutting edge (24) of the rotary cutter (22) does not bend when subjected to cutting resistance. However, when the cutting resistance is very large, an appropriate fixing diagonal member can be added from the tool post (2) to prevent the body (3) from being displaced.

Although not shown, the drive motor (7) sends a working oil from a hydraulic pump for generating a normal hydraulic pressure of 20 to 50 kg / cm ² to generate a driving force. It suffices that the rotary cutter (22) has a relative peripheral speed with the work material of 10 to 100 m / min at a rotation speed of 100 to 500 rpm. The rotation speed of the work material (26) is 10 rp.
It may be a proper value of about m. Within this range, it is possible to cut from ordinary raw materials to hardened and hardened steel materials exceeding HRc60.

More specifically, in this embodiment, the outer diameter is 50 mm, the blade length is 40 mm, and W is 70%.
Eight outer peripheral cutting edges (24) and side edges (25) having a twist angle of 30 degrees are formed on the above WC-Co type cemented carbide tip (23), and the diameter of the shank portion (16) is set to 16 mm. None,
The rotation speed is 125r due to the driving force from the driving motor (7).
pm (cutting speed is 20 m / min, relative peripheral speed is about 30 m / min). The surface of the cemented carbide tip (23) of the rotary cutter (22) has T
iN (titanium nitride) multi-layer coating is applied to improve wear resistance, and even at the above low speeds, HRc60
The above high hardness steel materials can be cut.

The rotary cutter (2
As described above, 2) can be removed by loosening the screw (21) of the cemented carbide tip (23), so that, for example, when the work material (26) is desired to have a groove, the blade width is narrow. By exchanging them, it is possible to form a groove having a required width. By changing the fixed angle of the body (3) with respect to the tool rest (2) in the horizontal plane, the surface of the work material (26) can be processed into a conical shape.

[0025]

As described above, the turning apparatus (1) of the present invention
Is a rotary cutter (twisted cutting edge (24) driven by a drive motor (7) and a side cutting edge (25) provided on a frame (3) fixed to a tool rest (2). Since the surface of the work material (26) is cut by 22), the ordinary cemented carbide chip (23) is coated with Ti.
Even if the N (titanium nitride) reinforced coating layer is formed, it is possible to turn the hardened steel material at a low cutting speed, and an expensive high-speed lathe or CBN (cubic boron nitride) is used. Or, without consuming rare materials such as diamonds as a cutter, the conventional lathe can be modified and converted into a new turning machine, which enables turning of various work materials, thus streamlining work. It has a great effect on the industry as it progresses to great energy.

Further, since the apparatus of the present invention uses the multi-blade rotary cutter (22) having a wide blade width, unlike the conventional throw away tip, the amount of the work material to be cut and removed is large, and the material can be removed in a short time. Since the turning process is completed, the work efficiency can be greatly improved.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment showing a cutting function portion of a turning apparatus of the present invention.

FIG. 2 is a left side view of FIG.

FIG. 3 is an explanatory view of a conventional turning device.

[Explanation of symbols]

1. Turning device part, 2. Turret, 3. Body,
4. Basal part of body, 5. Wall, 6. Wall, 7. Drive motor, 8. Axis, 9. Fixing bolt, 10. Pulley, 11. Power transmission belt, 12. Axis, 13. Pulley, 14. Gears for speed-up, 15. Body, 16.
Shank part, 17. Driven gear, 18. Blade part,
19. Screw holes, 20. Holding metal fittings, 21. Screw, 2
2. Rotary cutter, 23. Cemented carbide tip, 2
4. Peripheral cutting edge, 25. Side blade, 26. Work material, 2
7. Bearing, 28. Bearing, 29. Bearings, 3
0. bearing,

Claims (5)

[Claims] 1. A rotary cutter, which is driven by a motor, is provided on a body held by a tool rest, and the rotary cutter is brought into contact with an outer peripheral surface of a work material while being rotated,
Turning device for cutting the work material 2. The turning apparatus according to claim 1, wherein the rotary cutter has a twisted outer peripheral cutting edge and a side edge on its end surface. 3. The turning apparatus according to claim 1, wherein a reinforcing coating layer of titanium, boron, diamond or the like is formed on the surface of the blade portion of the rotary cutter. 4. The turning apparatus according to claim 1, wherein the relative peripheral speed between the rotary cutter and the outer periphery of the work material is a value of 10 to 100 m / min. 5. The turning apparatus according to claim 1, wherein the cemented carbide tip forming the blade portion of the rotary cutter is formed in a structure attachable to and detachable from the blade base portion.