JPH0577129A - Tool exchanging method for wet type machine tool using rotary tool - Google Patents

Abstract

PURPOSE:To provide a method by which, in a tool exchanging method for a wet-type machine tool to execute cutting or grinding work with coolant liquid poured on a rotary tool, the coolant liquid adhering to a tool section or the tapered part of a spindle and fine powder caused by grinding can be simply removed. CONSTITUTION:Before exchanging a tool 3, a spindle 1 is alternately rotated and stopped. Thus coolant liquid adhering to the tool 3 is shaken off, and fine powder also scatters together with the coolant liquid. The more the idle running and stopping of a wet-type machine tool are repeated, the more the coolant liquid and the fine powder can be surely removed. In addition, the mist of the coolant liquid and of the fine powder occurring during cutting or grinding process is extinguished as time elapses.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention uses a rotating tool,
The present invention relates to a tool changing method for a machine tool that cuts or grinds a work by applying a coolant liquid.

[0002]

2. Description of the Related Art A tool part of a wet machine tool for cutting or grinding a work while rotating the tool has a structure as shown in FIG. The figure illustrates a grinding machine as a machine tool. In this figure, reference numeral 1 is a rotary spindle of the grinding machine, and a tool unit A is attached to the tip thereof. The tool unit A is one in which a tool 3 is fastened and fixed to a tool holder 2 using a sleeve 4 and a nut 5.

The tool holder 2 has a frustoconical fitting part 2a for fitting in the tapered hole of the spindle 1 at the upper part,
An enlarged grip portion 2b is formed at the lower end of the fitting portion 2a, and a pipe-shaped male screw portion 2c is vertically provided below the grip portion 2b. The hollow part of the male screw part 2c along the axis of the tool holder 2 reaches the inside of the upper fitting part 2a and forms a cylindrical mounting hole 2d.

The tool 3 which is a grindstone (a cutting tool in the case of cutting) is inserted into this mounting hole 2d and fixed to the tool holder 2. Normally, the diameter of the mounting portion is equal to that of the mounting hole 2d. The diameter is smaller than the diameter, and the sleeve 4 is interposed between the tool holder 2 and the tool holder 2, and the nut 5 is tightened to fix the sleeve.

FIG. 2 shows the sleeve 4 described above. The sleeve 4 is composed of a cylindrical main body portion 4a and a collar 4b that is continuously provided at the right end of the main body portion 4a, and a plurality of grooves 4c are formed from the collar 4b to the middle of the main body portion 4a. Groove 4c
Is not formed in the vicinity of the left end of the body portion 4a in the figure, the sleeve 4 can maintain the integrity. Since the sleeve 4 and / or the mounting hole 2d are slightly tapered, when the nut 5 is tightened, the width of the groove 4c becomes narrower, and the tool 3 can be firmly tightened and fixed to the tool holder 2. ..

The tool unit A having the above structure is used for grinding (or cutting work), and when the grindstone (or bite) is worn, it is replaced with a spare tool unit by an automatic tool changer (hereinafter referred to as "ATC"). , The grinding operation is performed again. On the other hand, the worn tool 3 is removed from the tool holder 2, polished by a dresser or the like, and then assembled again like the tool unit A to be used many times. In the above grinding work, a wet method is usually adopted in order to prevent heat generation of the tool 3, and the tool 3 is cooled by injecting a coolant liquid.

However, in the above-mentioned prior art, the coolant liquid not only impinges on the tool 3 but also enters the groove 4c of the sleeve 4 and enters the gap between the tool 3 and the sleeve 4 from there by a capillary phenomenon or the like. Or the center hole 3 of the tool 3
Ascends to reach the upper part of the mounting hole 2d, drops from here, and enters the gap between the joint surfaces. And, importantly, this coolant liquid also contains fine powder generated by grinding and cutting, and if it is changed by ATC as it is, the surface of the tool 3 will rust after the coolant liquid dries. , The fine powder hardens and cannot be removed, and then it is tightened and fixed as it is, which damages the sleeve and the shank portion of the tool.

When the tool unit A is replaced, naturally, the injection of the coolant liquid is stopped, but the coolant liquid sprayed in the work up to that point and the fine powder generated by grinding or the like are also in a mist form. And floats around the tool unit A. This mist is always absorbed by the mist collector, but since the ATC is activated to replace the tool immediately after the rotation of the spindle 1 is stopped, there is no time for the mist to disappear, and the tool unit A is being replaced. Also attached to the newer tool unit. Therefore, the mist of the coolant or fine powder may enter the tapered portion of the spindle 1 and damage it as well.

To solve this problem, conventionally, before the replacement of the tool unit, the periphery of the tool is blown with air to scatter the coolant liquid.

[0010]

However, in order to completely remove the coolant liquid by air blow, it is effective only if the entire circumference is blown. Considering the timing and the position of the blow, the mechanism becomes very complicated. turn into.
Further, it is impossible to prevent the coolant liquid or fine powder floating as mist from increasing, and prevent the liquid from adhering to a tool or the like.

The present invention has been made to solve this problem, and an object of the present invention is to provide a method for easily removing the coolant or fine powder adhering to the tool portion, the taper portion of the spindle or the like.

[0012]

In order to achieve the above object, the present invention provides a tool changing method for a wet machine tool in which a rotating tool is subjected to cutting or grinding by applying a coolant liquid to the tool prior to the change. Alternate between rotation and stop,
After that, the tool is replaced.

[0013]

When the tool that has been used up to that time is idled and stopped before the tool is replaced, the coolant liquid is filtered out, and the fine powder also scatters together with the liquid. As the idling and stopping are repeated, the coolant liquid and the fine powder can be surely removed, and further, the mist generated during the cutting or grinding work disappears over time. After that, the tool is replaced.

[0014]

[Example] When exchanging tools with the grinding machine shown in FIG.
Before the normal ATC exchange operation is executed, the spindle 1 is rotated and stopped several times under the following conditions. (a) Spindle 1 rotation speed 3000 rpm (b) Rotation time 10 seconds (c) Stop time 2 seconds (d) Number of repetitions 5 times That is, total rotation stop time 12 seconds is 1 cycle,
Since it is repeated 5 times, the time required is 1 minute.

When the spindle 1 starts to rotate, the coolant liquid adhering to the tool 3 etc. is removed by centrifugal force. Furthermore, it is also eliminated by the inertial force when stopping. Since the liquid at this time becomes a droplet and flies and does not become a mist, it does not float around and adhere to the tool or the like again. The fine powder flows with the coolant and is screened out. On the other hand, the mist is the above 1
It disappears naturally within a minute, or it almost disappears after being sucked into the mist collector.

As a matter of course, it is more effective that the rotation and stop are as rapid and sudden as possible. It is needless to say that the numerical values shown above are only one example until the tiredness, and the optimum value should be selected from the situation of the coolant liquid remaining in the tool 3 and the disappearance state of the mist. Also,
This method can also be applied to a cutting machine that uses a cutting tool.For a machine tool, a vertical type is more suitable because the coolant liquid flows downward, but a horizontal type can also be expected to have a considerable effect. is there.

Since a machine tool equipped with an ATC device is normally automatically operated by a computer program, if the operation at the time of replacement is also incorporated in the program, it can be easily automated. You can

[0018]

As described above, according to the present invention, a tool for a machine tool can be protected from rust and damage by a simple method. Further, not only the tool but also the spindle of the machine tool can be protected at the same time, so that it is possible to prolong the service life of both the machine and the tool.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a tool unit in a wet machine tool that uses a rotary tool.

FIG. 2 is a perspective view of a sleeve.

[Explanation of symbols]

 1 Spindle 2 Tool holder 3 Tool 4 Sleeve 5 Nut

Claims (1)

[Claims] 1. A method for exchanging a tool for a wet machine tool, in which a coolant is applied to a rotating tool to perform cutting or grinding, and the tool is alternately rotated and stopped prior to the exchanging,
A tool changing method for a wet machine tool using a rotary tool, characterized in that the tool is then changed.