JPH08281533A - Thermal displacement preventing device for column in machine tool - Google Patents

Abstract

PURPOSE: To make temperature in the inner and outer wall of a column uniform to secure the straightness of the column in a machine tool provided with a spindle head and a spindle driving motor in the column. CONSTITUTION: A thermal displacement preventing device is composed of a suction duct 9a opened toward the inside of a column 1 at one end; an exhaust duct 9b opened along the outer wall 1b of the column 1 through a throttle 10 at the other end; and a fan 11 which is provided between the suction duct 9a and the exhaust duct 9b and generates an air flow from the inside of the column 1 toward its outer wall 1b, and an air-curtain generating device 8 for forming an air layer (air curtain) on the outer wall 1b of the column 1 of air in the column 1 is severally provided on both the sides of the rear back of the column 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a column thermal displacement prevention device in a machine tool equipped with a spindle drive motor.

[0002]

2. Description of the Related Art In a machine tool having a motor for driving a spindle in a column, the temperature in the column becomes high due to heat generated by the motor for driving the spindle, and thermal displacement occurs in the column. In order to prevent this, an invention is disclosed in Japanese Utility Model Laid-Open No. 1-156842 in which an exhaust duct communicating with an exhaust port of a motor for driving a spindle is provided and which is open to the outside of a column.

According to this, high temperature air is discharged from the exhaust port of the main shaft drive motor to the outside of the column through the duct, so that thermal displacement of the column due to heat generation of the main shaft drive motor can be prevented.

[0004]

By the way, when high temperature air is discharged to the outside of the column, the outside air temperature outside the column generally becomes high at the top of the column due to natural convection.
There is a temperature difference between the upper and lower parts of the column. Also,
Because the heat of the spindle drive motor cannot be completely discharged,
There is a temperature difference between the top and bottom of the column. As a result, a temperature difference occurs inside and outside the column. There is a problem that thermal displacement occurs in the column due to the temperature difference between the inside and outside of the column and the upper and lower sides, the straightness of the column decreases, and the processing accuracy is adversely affected.

In view of the above problems, an object of the present invention is to make the inner and outer walls of the column uniform in temperature and ensure the straightness of the column.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention is characterized in that in a machine tool having a column with a spindle head and a spindle driving motor, the column has an air inside the column. Is provided along the outer wall of the column, and an air curtain generating device for forming an air layer on the outer wall of the column is provided.

Further, the air curtain generator is provided with a column, one end of which is opened in the column and the other end of which is narrowed along the outer wall of the column, and a duct which is provided in the duct and passes through the duct. It is composed of a fan that generates a flow of air from the inside toward the outer wall of the column.

[0008]

With the above structure, the heated air in the column is discharged to the outside of the column to form an air layer (air curtain) on the outer wall of the column, and the outer wall of the column is shielded from the outside air by the air layer. And equalize the temperature distribution above and below,
That is, the temperature is soaked to prevent thermal displacement of the column.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, it is one column, and as shown in FIG. 2, it is slidably mounted on the bed 2 and is moved forward and backward by the column feed motor 14. Reference numeral 3 denotes a spindle head, which is guided by the front portion of the column 1 so as to be vertically movable, and is vertically moved by a spindle head lifting motor 7.

A spindle 4 is rotatably supported by the spindle head 3, and a tool 5 is detachably held at the tip of the spindle 4. The main spindle 4 is coupled with a main spindle driving motor 6 installed in the column 1 and is rotationally driven by the main spindle driving motor 6. In FIG. 1, 1
5 is a ventilation fan for the ceiling, which is arranged on the ceiling on the upper surface of the column 1 and discharges the heat of the spindle drive motor 6.

Reference numeral 8 is an air curtain generator. The air curtain generators 8 are installed on the left and right sides of the rear surface of the column 1.

As shown in FIG. 3, the air curtain generator 8 has an air intake duct 9a opening into the column 1 along the inner wall 1a of the column 1 and an outer wall 1b of the column 1, The exhaust duct 9b is provided with a diaphragm 10 at its opening, and the fan 11 is arranged between the intake duct 9a and the exhaust duct. The fan 11 may be a propeller type or a sirocco type.

The intake duct 9a and the exhaust duct 9b extend in the vertical direction of the column 1. Therefore, the opening of the intake duct 9a and the opening of the exhaust duct 9b where the diaphragm 10 is provided also extend in the vertical direction.

A plurality of the fans 11 are arranged so as to correspond to the ventilation holes 16a and 16b which are provided at a predetermined interval in the vertical direction of the intake duct 9a and the exhaust duct 9b.

Since the present invention is constructed as described above, the air heated in the column 1 is sucked by the fan 11 by the intake duct 9a, and the air layer 12 (air curtain) along the inner wall 1a of the column 1 is drawn. Is formed.

Further, the air in the column 1 sucked by the intake duct 9a enters the exhaust duct 9b, and the throttle 10 provided at the opening compresses the air in the exhaust duct 9b and equalizes the temperature. , An air layer 13 discharged from the opening of the diaphragm 10 and extending along the outer wall 1b of the column 1.
(Air curtain) is formed.

The temperature of the air used in the air curtain generator 8 is the inside of the column 1 because the heat of the spindle drive motor 6 is discharged to the outside by the ceiling ventilation fan 15 above the column 1. Is not so hot that it is thermally displaced. Therefore, the inner wall 1a and the outer wall 1 of the column 1 are
The air layers 12 and 13 (air curtain) formed along b are in a temperature range where thermal deformation does not occur in the column 1, and the air layers 12 and 13 (air curtain) cause the column inner and outer walls 1a, 1b and the upper and lower sides are forcibly temperature-uniformized, and the column inner and outer walls 1a and 1b of the column 1 are
Also, thermal displacement of the column due to the temperature difference between the upper and lower sides is prevented.

[0018]

As described above, according to the present invention, the air inside the column heated by the motor is discharged to the outside to prevent the air inside the column from staying, and the outer wall of the column is formed by the air inside the column. Since it is shielded from the outside air by the air layer (air curtain), it is less likely to be affected by the outside air temperature, and the temperature difference between the inside and outside walls of the column and the top and bottom becomes smaller, resulting in a uniform temperature distribution inside and outside the column.
The thermal displacement of the column is reduced, the straightness of the column is secured,
Prevents deterioration of processing accuracy.

Further, since the air curtain generator compresses the air after passing through the fan by the throttle at the opening of the duct, a stable air layer (air curtain) is formed along the outer wall of the column up to the front of the column. Can be formed.

[Brief description of drawings]

FIG. 1 is a plan view of a column equipped with the device of the present invention.

FIG. 2 is a rear view of a column equipped with the device of the present invention.

FIG. 3 is a sectional view of an air curtain generator.

[Explanation of symbols]

 1 column 1a inner wall of column 1b outer wall of column 2 bed 3 spindle head 4 spindle 5 tool 6 spindle drive motor 7 spindle head lifting motor 8 air curtain generator 9a intake duct 9b exhaust duct 10 throttle 11 fan 12 air layer (Air curtain) 13 Air layer (Air curtain) 15 Ventilation fan for ceiling

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Nagami 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Tatsuya Yamamoto 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation ( 72) Inventor Koichi Sugiura 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd.

Claims (2)

[Claims] 1. A machine tool having a spindle head and a spindle driving motor in a column, wherein air inside the column is discharged to the column along the outer wall of the column to form an air curtain on the outer wall of the column. A column thermal displacement prevention device in a machine tool, which is provided with a device. 2. An air curtain generator is provided in a column, one end of which is opened in the column, and the other end of which is narrowed along the outer wall of the column, and a duct which is provided in the duct and passes through the duct in the column. 2. A column thermal displacement prevention device in a machine tool according to claim 1, wherein the column thermal displacement prevention device comprises a fan for generating an air flow from the column to the column outer wall.