JP2002144177A - Spindle device for machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spindle device allowing the direct measurement of temperature of a rolling bearing. SOLUTION: This spindle device is provided with a spindle 55, a rolling bearing 51 composed of an outer ring 51a, an inner ring 51b and rolling elements 51c to rotatably support the spindle 55, and a housing 11 for enclosing and holding the rolling bearing 51. An inspection hole 10 with one end opened into a position facing the outer peripheral surface of the outer ring 51a of the rolling bearing 51 and with the other end opened to the outer surfaces of the housings 11, 12, is formed in the housings 11, 12. The temperature of the outer ring 51a of the rolling bearing can be directly measured through the inspection hole 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a main shaft, a bearing for rotatably supporting the main shaft, a rolling bearing comprising an outer ring, an inner ring and a rolling element, and a housing for accommodating and holding the rolling bearing. The present invention relates to a spindle device of a machine tool including:

[0002]

2. Description of the Related Art As an example of the above-described spindle device, a spindle device constituting a machining center is illustrated in FIG. still,
FIG. 2 is a cross-sectional view showing a part of the spindle device in a cross section.

[0003] As shown in FIG.
A rolling bearing 51 including an outer ring 51a, an inner ring 51b, and a rolling element 51c, a housing 52 for accommodating the rolling bearing 51, a main shaft 55 rotatably supported by the rolling bearing 51, and a position of the outer ring 51a of the rolling bearing 51. An outer race spacer 58 for regulating the position of the inner race 51b of the rolling bearing 51; an outer cover 53 for covering the outer periphery of the housing 52;
And a front cover 54 that covers the front end of the camera.

An annular groove 52a is formed on the outer peripheral surface of the housing 52. Cooling liquid is supplied from a cooling liquid supply source (not shown) to the annular groove 52a.
The main spindle device 50 can be cooled by the coolant circulating in the inside a. In the drawing, reference numeral 56 denotes a draw bar, and 57 denotes a collet, which functions to fasten the tool T to the main shaft 55.

[0005]

By the way, the rolling bearing 51 constituting the above-mentioned spindle device 50 is subjected to a large preload in order to obtain a proper rotation accuracy, or due to wear over time, during rotation of the spindle. The temperature rises violently. When the temperature rises as described above, the thermal deformation of the spindle device 50 increases with this, and the machining accuracy decreases. Therefore, conventionally, the temperature of the spindle device 50 is measured to predict the thermal deformation of the spindle device 50, and based on the predicted thermal deformation data, the error caused by the thermal deformation is corrected, and the temperature rise is based on a certain standard. When it exceeded, it was replaced as a bearing failure (life).

Further, since the conventional spindle device 50 has a structure in which the rolling bearing 51 is completely housed in the housing 52, the temperature of the rolling bearing 51 as a heat source cannot be directly measured. , For this reason,
The temperature of the outer peripheral cover 53 and the front cover 54
1, the outer peripheral cover 53 and the front cover 5
The thermal deformation was predicted based on the temperature obtained by measuring the outer surface of No. 4.

However, it is difficult to accurately predict the thermal deformation of the entire spindle device 50 by measuring the outer surface temperature of the outer peripheral cover 53 and the front cover 54 which are far away from the rolling bearing 51. The life of 51 cannot be accurately determined. In particular, the housing 5
In the main shaft device 50 having the above-described structure for cooling the cooling device 2,
There is a large difference between the outer surface temperature of the outer peripheral cover 53 and the front cover 54 and the temperature of the rolling bearing 51.

The present invention has been made in view of the above circumstances, and has as its object to provide a spindle device capable of directly measuring the temperature of a rolling bearing.

[0009]

Means for Solving the Problems and Effects There is provided an invention according to claim 1 of the present invention for solving the above-mentioned problems, comprising a main shaft and a bearing for rotatably supporting the main shaft, comprising an outer ring,
In a spindle device of a machine tool including a rolling bearing composed of an inner ring and a rolling element, and a housing for housing and holding the rolling bearing, one of the opening is located at a position facing an outer peripheral surface of an outer ring of the rolling bearing, An inspection hole is formed in the housing, the inspection hole being opened on the outer surface of the housing.

According to the spindle device of the present invention, the inspection hole is formed in the housing, one of which is opened at a position facing the outer peripheral surface of the outer ring of the rolling bearing, and the other is formed in the housing. The temperature of the rolling bearing can be measured directly from the inspection hole. That is, when a contact-type thermometer is used, the temperature of the rolling bearing can be directly measured by inserting it into an inspection hole and bringing its detection portion into contact with the outer ring of the rolling bearing. In the case of using the thermometer, the temperature of the rolling bearing can be directly measured by detecting the physical information of the outer ring of the rolling bearing obtained through the inspection hole by a non-contact thermometer. Therefore, when predicting the thermal deformation of the spindle device, it is possible to accurately predict the thermal deformation, and correct the error caused by the thermal deformation. Further, it is possible to accurately determine the life of the rolling bearing.

According to a second aspect of the present invention, in the first aspect of the present invention, the inspection hole is detachably engaged with the inspection hole opening opening on the outer surface of the housing, and the opening is sealed. A sealing member is provided. According to the present invention, when the temperature of the rolling bearing is not measured, the inspection hole can be sealed by the sealing member. Therefore, it is possible to effectively prevent the inconvenience that foreign matter invades from the inspection hole and the rolling bearing is damaged by the invading foreign matter.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a sectional view showing a spindle device 1 according to the present embodiment. As shown in the figure, the spindle device 1 of the present embodiment is an improvement of the conventional spindle device 50 shown in FIG.
The configuration of the outer peripheral cover 12 is different from that of the housing 52 and the outer peripheral cover 53 in the conventional spindle device 50.
Therefore, the same components as those of the conventional spindle device 50 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 1, a spindle device 1 according to the present embodiment comprises:
It comprises an inspection hole 10 formed in a housing 11 and an outer peripheral cover 12 which constitute this. Note that the housing 11 and the outer peripheral cover 12 of this embodiment correspond to the housing described in claim 1 above.

As shown, the inspection hole 10 has an opening at a position facing the outer peripheral surface of the outer ring 51 a of the rolling bearing, and the inspection hole 10 has an opening at the outer peripheral surface of the outer peripheral cover 12. It is formed on the cover 12. In addition, a sealing member 13 is screwed into the opening of the inspection hole 10 opened on the outer peripheral surface of the outer peripheral cover 12.

To measure the temperature of the rolling bearing 51 in the spindle device 1 of the present embodiment having the above configuration, first,
The sealing member 13 screwed to the outer peripheral cover 12 is removed,
The inspection hole 10 is opened. Next, the opened inspection hole 1
The temperature of the rolling bearing 51 is directly measured from zero.

That is, for example, when measurement is performed using a contact-type thermometer such as a thermocouple, this is inserted into the inspection hole 10 and its detection portion is brought into contact with the outer ring 51 a of the rolling bearing 51. The temperature can be measured directly, and when measuring using a non-contact type thermometer such as an infrared temperature sensor, infrared rays emitted from the outer ring 51 a of the rolling bearing 51 are detected through the inspection hole 10. , Its temperature can be measured directly.

Then, as described above, the rolling bearing 5
After measuring the temperature of 1, the sealing member 13 is screwed into the opening of the inspection hole 10, and the opening is sealed again by the sealing member 13.

As described above, according to the spindle device 1 of the present embodiment,
Since the temperature of the rolling bearing 51 can be directly measured, when the thermal deformation of the spindle device 1 is predicted, it is possible to accurately predict the thermal deformation and to correct the error caused by the thermal deformation. Can be done accurately. In addition, it is possible to accurately determine the life of the rolling bearing 51.

When the temperature measurement is not performed, since the opening of the inspection hole 10 is sealed by the sealing member 13, foreign matter enters the rolling bearing 51 from the inspection hole 10 and is damaged. The inconveniences described above can be effectively prevented.

As described above, one embodiment of the present invention has been described in detail, but it is needless to say that a specific embodiment of the present invention is not limited to this. For example, in the above-described example, a thermometer is appropriately installed and measurement is performed only at the time of measurement of the rolling bearing 51. However, a thermometer may be always installed and measurement may be performed. In this case, thermometer and inspection hole 1
0 is sufficiently sealed with the opening of the inspection hole 10
It is preferable to prevent intrusion into the inside.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a spindle device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional spindle device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spindle apparatus 10 Inspection hole 11 Housing 12 Outer peripheral cover 51 Rolling bearing 51a Outer ring 51b Inner ring 51c Rolling element 54 Front cover 55 Main shaft

Claims (2)

[Claims] 1. A machine comprising: a main shaft; a bearing rotatably supporting the main shaft, the rolling bearing including an outer ring, an inner ring, and a rolling element; and a housing for accommodating and holding the rolling bearing. A main spindle device for a machine tool, wherein an inspection hole is formed in the housing, one of which is opened at a position facing an outer peripheral surface of an outer ring of the rolling bearing, and the other is opened at an outer surface of the housing. 2. The machine tool according to claim 1, further comprising a sealing member detachably engaged with the inspection hole opening opening on the outer surface of the housing and sealing the opening. Spindle device.