JPH07204993A - Reference position detecting device for rotary cutter tool - Google Patents

Abstract

PURPOSE:To automatically detect a reference position of a rotary cutter tool in an automatic exchange device for throw-away tips. CONSTITUTION:A probe 16 of a measuring head 9 is made into contact with a cutting edge of a throw-away tip 6 mounted to a rotary cutter tool 2. A displacement at this time is detected by a displacement sensor 12, and a reference position is calculated from a relationship between the detected displacement and a turning angle of an indexing table 1. Accordingly, the position of the throw-away tip 6 or a mounting screw 7 can be automatically adjusted to a position where a gripper hand or a nut runner in an automatic exchange device is operated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reference position detecting device which constitutes a part of an automatic indexable tip exchange device mounted on a rotary cutting tool.

[0002]

2. Description of the Related Art The present inventors have already invented an automatic cutting blade tip changing device for a milling tool and applied for a patent (Japanese Patent Application No. 4-308292). For example, in the automatic exchange device as described above, the fixed position of the rotary cutting tool attached to the indexing table in the automatic exchange device and the position in the rotational direction of the throw-away tip attached to the tool body are
How they are related is a very important technical issue in identifying the positions where the grip hands and nut runners for attaching and detaching the throw-away tip operate.

The fixed position of the rotary cutting tool is generally determined by a key groove or a mounting hole provided in the tool body.
Since the rotary cutting tool is used while being rotated, the positional relationship between the installation position of the key groove or the mounting hole and the cutting edge in the rotational direction does not matter. Therefore, usually
Between them, they are not manufactured with extremely high precision.

However, in the throw-away tip automatic exchange device, high accuracy is required for the above-mentioned reasons. And one of the means to solve it is a method to add a pin hole or a key groove as a reference point to the rotary cutting tool with high accuracy later, and as another means, it is a tool body on an automatic changer. This is a method of measuring the relationship between the fixed position of and the position of the throw-away tip.

FIG. 5 shows an example of a conventional technique, which is measured by using a dial gauge 17. A front milling cutter 2, which is a rotary cutting tool, is fixed to the indexing table 1, and a key 3 is fitted to the rear face portion thereof. The probe 16 is brought into contact with the cutting edge of the throw-away tip 6 attached to the front milling cutter 2 from the rake face side, and the displacement of the probe 16 is moved through the L-shaped lever lever 13 to the other end of the lever lever 13. Then, the relationship between the reference point and the throw-away tip 6 is measured by reading the dial gauge 17 that comes into contact therewith, and thus the position of the screw 7 is also specified.

[0006]

When the indexable insert of the rotary cutting tool is automatically replaced by the automatic replacement device,
The relationship between the fixed position of the rotary cutting tool, which is determined by the key groove and mounting hole, and the mounting position of the throw-away tip, is important. It becomes a factor of. In addition, it requires extra labor and cost to add a key groove or pin hole with high accuracy afterwards for a rotary cutting tool that is automatically replaced.

On the other hand, as described in the prior art, although the measuring method using the dial gauge is also effective, since the measuring and the correction based on the measured data are manual operations,
It was incomplete as an automatic device.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is designed to automatically detect and correct the reference position of a rotary cutting tool in a throw-away tip automatic changing device. Is.

In the rotary cutting tool, a throw-away tip is mounted on the tool body by a direct screw or a wedge by a screw action. The automatic changer controls at least an indexing table to which the rotary cutting tool is attached, a gripping hand for gripping the throw-away tip, and a nut runner that gives the screw forward and reverse rotation motions. And a numerical control device for doing so.

The positional relationship in the rotational direction between the reference point of the rotary cutting tool mounted on the indexing table and the throw-away tip mounted on this rotary cutting tool is such that the blade tip of the throw-away tip abuts from the rake face side. It is detected by the measuring head. The displacement detected by the probe of the measuring head is transmitted as the displacement of the other end through the L-shaped lever lever part, and is detected by the displacement sensor that is in contact with the displacement. The detection by the displacement sensor and the rotation angle of the indexing table are always fed back to the numerical control device, and the positions of the throw-away tip, the screw and the like are obtained based on the measurement result.

[0011]

With the reference position detecting device for the rotary cutting tool of the present invention, the relationship between the fixed position of the rotary cutting tool and the mounting position of the throw-away tip can be automatically measured.
The measurement data is fed back to the numerical control device, and as a result, the position of the rotary cutting tool can be automatically adjusted to the operating position of the grip hand, nut runner, etc., and complete automation of the automatic changer is achieved. . It should be noted that indexing between the indexable inserts, which are normally mounted on a plurality of sheets, is highly accurate because most of the rotary cutting tools are currently manufactured in a machining center.
Therefore, it is not necessary to measure the total number of throw-away chips, and it is sufficient to measure only one reference chip.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a reference position detecting device for a rotary cutting tool according to the present invention will be described with reference to the drawings.

In FIG. 1, a face milling cutter 2 which is a rotary cutting tool is mounted on the surface of an indexing table 1 which constitutes a part of an automatic changer. The position of the front milling cutter 2 is determined by the key 3 fitted on its rear face. Multiple throw-away chips 6 on the front side of the front milling cutter
Is installed.

The method of mounting the throw-away tip 6 in this embodiment is as follows. For example, if the rotary cutting tool utilizes the action of the screw, such as directly mounting the throw-away tip with a hole by a screw. Any structure may be used.

A locator 4 is provided in a mounting groove provided on the tool body.
Is fixed by a tightening screw 5, and a throw-away tip 6 is attached to a tip seat provided on the locator 4. The throw-away tip 6 is pressed and fixed in the mounting groove by actuating a screw 7 screwed into the tool body and causing the wedge 7 to sink by its thrust. The nut runner of the automatic changer acts on the screw 7 to enable automatic attachment / detachment of the throw-away tip.

The position of the throw-away tip 6 is previously measured by the measuring head 9 in order to align the front milling cutter 2 with the operating position of the grip hand, nut runner or the like. As shown in FIG. 2, the measuring head 9 is formed of an adapter 11 incorporated in the moving shaft end 10, a displacement sensor 12 gripped by the adapter 11, and a lever 13.

The lever lever 13 is an L-shaped member rotatable about a fulcrum 14, and a probe 15 of the displacement sensor 12 is brought into contact with one end of the lever lever 13. The other end is a probe 16, and at the time of measurement, the probe 16 is brought into contact with the cutting edge of the throw-away tip 6 and the displacement amount is transmitted to the displacement sensor 12 via the lever lever 13. The blade edge position of the throw-away tip 6 is calculated from the detection by the displacement sensor 12, the current position of the measuring head 9 and the rotation angle of the indexing table 1.

The method of detecting the cutting edge position will be described in more detail with reference to the system flowchart of FIG. 3. First, the movable shaft end 10 is slid to a position suitable for measurement,
The slide position is automatically measured. Next, the front milling cutter 2 on the indexing table 1 is rotated at a relatively high speed from a certain reference point until the cutting edge of the throw-away tip 6 contacts the probe 16. The blade edge position can be specified by the rotation angle from the reference point of the indexing table 1 when the displacement detected by the displacement sensor 12 reaches a predetermined value, but in reality it is determined by the first contacting operation. Overruns the value.

Then, reverse rotation is performed at medium speed to bring the value closer to the predetermined value by the amount of overrun, but this time, reverse overrun occurs, and the predetermined value is slightly reached. Finally, in order to correct the reverse overrun, low-speed forward rotation is performed again to adjust the cutting edge to a predetermined value. The overrun in the final operation is negligibly small due to the low speed.

FIG. 4 shows the control relationship of this apparatus. The displacement data detected by the displacement sensor 12 is amplified by the amplifier and sent to the sequencer through the interface. The rotation angle of the indexing table 1 is also controlled by the sequencer to form a control system.

In the detection by the reference position detection device of the rotary cutting tool of the present invention, conventionally, it is 2 in the measurement by the dial gauge.
Although it took ~ 3 minutes, it became possible to measure in about 20 seconds, and a series of operations became fully automatic.

[0022]

As described above, by incorporating the reference position detecting device of the rotary cutting tool of the present invention into the automatic indexing tool changing device, the reference point of the rotary cutting tool fixed on the indexing table and the throw away tip. It becomes possible to automatically measure the positional relationship with, and it becomes possible to quickly align the throw-away tip, mounting screw, etc. to the operating position of the grip hand, nut runner, etc., and fully automatic exchange The device can be realized.

[Brief description of drawings]

FIG. 1 is a partial explanatory view showing an embodiment of a reference position detecting device for a rotary cutting tool according to the present invention.

FIG. 2 is a perspective view showing an embodiment of a measuring head.

FIG. 3 is a flowchart showing a measurement system of this device.

FIG. 4 is a control configuration diagram of the present apparatus.

FIG. 5 is a partial explanatory view showing a conventional example of a reference position detecting device for a rotary cutting tool.

[Explanation of symbols]

 1 Indexing table 2 Front milling cutter 3 Key 6 Throw-away tip 7 Screw 9 Measuring head 12 Displacement sensor 13 Lever lever 16 Transducer

Claims (3)

[Claims] 1. An indexing table to which a rotary cutting tool having a throw-away tip mounted on the outer edge portion and / or inner diameter portion of a tool body is attached by a direct or indirect action of a screw, and the throw-away tip is gripped. Rotary hand in an automatic indexing device for indexable inserts, which comprises at least a gripping hand for controlling the rotation of the screw, a nut runner capable of imparting normal and reverse rotational motions to the screw, and a numerical controller for controlling these. A reference position detecting device for a tool, in which a position of a throw-away tip 6 mounted on a rotary cutting tool 2 on an indexing table 1 is brought into contact with a throw-away tip 6 by a measuring head 9 having a displacement sensor 12 incorporated therein. A reference position detection device for a rotary cutting tool, which is characterized in that the detection is performed. 2. The measuring head 9 is formed so that the displacement of the probe 16 contacting the cutting edge of the throw-away tip 6 is transmitted to the displacement sensor 12 via the lever lever 13. The reference position detection device for a rotary cutting tool according to claim 1. 3. The cutting edge position is calculated by feeding back the detection by the displacement sensor 12 and the rotation angle of the indexing table 1 to a numerical control device. A reference position detecting device for a rotary cutting tool as described in 1.