JPH08309644A - Device for cooling lubrication oil for main shaft - Google Patents

Abstract

PURPOSE: To provide a device for cooling, lubrication oil for a simple execution, wherein an amount of lubrication oil of a bearing portion and an amount of cooling oil of a main shaft are compositely controlled corresponding to a rotational speed of the main shaft. CONSTITUTION: A separator cylinder 5 for providing a bearing supporting region BS of a main shaft at a hole wall in an annular space formed by inserting a drawing bar 2 is arranged in a hole of the main shaft for feeding lubrication oil through a tail end of the main shaft. A first hole for feeding lubrication oil to a cylinder wall of the separator cylinder confronting with the bearing supporting region BS. The first hole is connected to a second hole located at the main shaft 1 in the bearing supporting region BS. The second hole located at the main shaft 1 is connected to third holes located at inner walls 3A, 4A of each bearings 3, 4. A throttle valve 20 is located at the first hole at the separator cylinder. While the main shaft 1 is stopped or rotated at low speed, the throttle valve 20 is released to increase a lubricate amount Q1. While the main shaft 1 is rotated at high speed, the throttle vale 20 is squeezed to reduce the lubrication amount Q1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to underrace lubrication of a main shaft bearing of a machine tool and cooling of the main shaft, and in particular, it is possible to simply carry out complex control of the lubricating oil amount of the bearing part and the cooling oil amount of the main shaft part. The present invention relates to a spindle cooling and cooling device.

[0002]

2. Description of the Related Art Conventionally, as for underrace lubrication for a main shaft bearing of a machine tool, it has been proposed to supply lubricating oil from a hollow portion inside a rotary shaft to a bearing mounted on the outer peripheral side of the rotary shaft. There is. This under-race lubrication sends a large amount of lubricating oil from the outside to the hollow shaft of the rotating shaft, penetrating radially from the hollow part of the rotating shaft to the bearing, and excess lubricating oil from the gap of the sending part. It was designed to be collected. Therefore, since the hollow part of the rotating shaft is always filled with lubricating oil, the lubricating oil is uniformly and sufficiently supplied to all bearings supporting this rotating shaft regardless of their axial positions. Is what you can do.

[0003]

However, according to the above underrace lubrication, since the lubricating oil supply pipe is arranged in the state where the clearance is provided at the tail end of the hollow portion of the rotating shaft, the clearance is crossed. It is easy to cause runout at this intersection and cannot be applied to a high-speed rotating spindle. This phenomenon also has an adverse effect on the accuracy of lubricating oil feeding, and the uniform supply of lubricating oil cannot be guaranteed, so that the effect of cooling the bearing portion of the main shaft cannot be fully exerted. Furthermore, since the amount of lubricating oil to the bearing portion of the spindle is controlled to be constant, it is desirable to increase the lubricating flow rate in the section from the stop of the spindle to the low speed rotation range with respect to the spindle rotation speed. I can't do this. If the lubricating flow rate is not reduced so that the main shaft rotates at a high speed, an excessive lubrication flow rate causes an adverse problem of increasing the amount of heat generated from the bearing portion of the main shaft.

In view of the problems of the above-mentioned conventional underlace lubrication system, the present invention enables simple control of the composite control of the lubricating oil amount of the bearing portion and the cooling oil amount of the main spindle portion in accordance with the main spindle rotation speed. An object of the present invention is to provide a lubrication cooling device.

[0005]

In order to achieve the above object, the present invention provides the annular space according to claim 1 by inserting a drawing bar into the spindle hole into which lubricating oil is fed from the tail end side of the spindle. A separator cylinder for supporting the bearing support region of the main shaft is internally provided in the inner hole wall, and a first through hole for feeding lubricating oil is provided in the cylinder wall of the separator cylinder facing the bearing support region. The hole is connected to a second through hole formed in the main shaft of the bearing support region, and the second through hole formed in the main shaft is connected to a third through hole formed in the inner ring of each bearing, and the second hole of the separator cylinder is connected. Lubrication cooling of the main shaft characterized by arranging a throttle valve in one through hole, and this throttle valve releases the lubricating flow rate from the stop of the main spindle to the low speed rotation range and throttles the lubricating flow rate as the main spindle rotates at higher speed. It is a device.

In order to achieve the above object, the present invention provides claim 2.
In the spindle hole for feeding the lubricating oil from the tail end side of the spindle, a separator cylinder for supporting the spindle supporting shaft region is provided inside the hole wall in the annular space obtained by inserting the drawing bar, and the above-mentioned support is performed. A fourth through hole for feeding the lubricating cooling liquid is provided in the cylinder wall of the separator cylinder facing the axial region, and the fourth through hole is provided.
A through hole communicating with the main shaft of the support shaft region and
A control valve is arranged in the through hole, and this control valve limits the lubricating cooling amount in the section from the stop of the main spindle to the low speed rotation range, and increases the lubricating cooling amount as the main spindle rotates at high speed. This is a lubrication cooling device.

In order to achieve the above object, the present invention provides claim 3.
In the lubrication cooling device for a spindle according to claim 1, the throttle valve exhibits a fully opened state in which the valve element is opened to the maximum by elastic force of the spring when the spindle is stopped and rotated at low speed, and when the spindle rotates, The valve body pushed back toward the center side is characterized in that the tapered surface approaches the tapered surface of the valve hole body and finally closes against the elastic force of the spring due to the centrifugal force generated by its own weight. This is a lubrication cooling device for the main shaft.

In order to achieve the above-mentioned object, the present invention provides a method according to claim 4.
In the spindle lubrication cooling device according to claim 2, the control valve exhibits a fully closed state of the valve body due to the elastic force of the spring when the spindle is stopped and rotates at a low speed, and when the spindle rotates, the control valve moves toward the center side by the spring. Lubrication cooling of the main shaft, characterized in that the pushed valve element moves the tapered surface away from the tapered surface of the valve hole body against the elastic force of the spring due to the generation of centrifugal force due to its own weight, and finally opens fully. It is a device.

[0009]

According to the first and third aspects of the present invention, since the throttle valve is provided in the through hole formed in the cylinder wall of the separator cylinder facing the bearing support area of the main shaft, the throttle valve of this separator cylinder is provided with the lubricating oil. When this fluid is sent, this lubricating fluid is communicated from the throttle valve of the separator cylinder through the through hole in the bearing support region and the through hole formed in the main shaft to the through hole formed in the inner ring of the bearing. The inner ring and balls of this bearing will be lubricated and cooled.In addition to increasing the lubrication flow rate in the section from the stop of the main spindle to the low speed rotation range, the lubrication flow rate should be reduced as the main spindle rotates at higher speeds. To prevent excessive lubrication flow rate in the bearing portion and suppress heat generation.

According to the second and fourth aspects of the present invention, since the control valve is provided in the through hole formed in the cylinder wall of the separator cylinder facing the support shaft region of the main shaft, the control valve of this separator cylinder is provided. The cooling fluid sent from the inside of the spindle to the inner peripheral surface is discharged from the tail end of the main spindle after cooling the main spindle from its inner peripheral wall. Since the section cools down the lubricating cooling amount and acts so as to increase the lubricating cooling amount as the spindle rotates at higher speed, the cooling action of the spindle increases in proportion to the spindle rotation speed, and the ideal cooling characteristics are simple and simple. It can be carried out easily.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments shown in the drawings will be described below. FIG. 1 is a vertical cross-sectional view showing an entire underrace lubrication cooling device for a main shaft bearing of a machine tool according to the present invention.
[Fig. 3] is a cross-sectional view of a main part according to the present invention. FIG. 4 shows the characteristics of the throttle valve and the control valve.

First, in FIG. 1, the main shaft 1 is supported at its tip end side by two bearings 3 and 4, and although not shown, the rear end side is also supported by the bearings. Furthermore,
Although not shown, the main shaft 1 has a rotor of a built-in motor fitted in the middle abdomen thereof, and a multi-layer disc spring and a drawing bar 2 are installed in the inner peripheral hole 1A opened at the shaft center position, and the main shaft tip The tool inserted in the taper hole 1B is strongly pulled in and fitted. An unclamping device is provided at the rear end of the drawing bar 2, and when the drawing bar 2 is advanced to the drawing bar side, the drawing bar is strongly pushed out to perform the unclamping operation.

The tail end hole portion 1C of the main shaft 1 is supplied with a cooling lubricating liquid C for cooling the shaft core of the main shaft 1 and for underrace lubrication of the bearings 3 and 4. Then, in the annular space 1D between the drawing bar 2 inserted through the tail end hole portion 1C and the hole wall 1E of the main shaft, a separator cylinder for separately bearing the bearing support region BS and the support shaft region SS of the main shaft 1. It has 5 interiors. The bearing support area BS
Further, through holes 5C and 5D for feeding the cooling lubricating liquid C for lubricating and cooling are provided in the respective cylinder walls 5A and 5B of the separator cylinder 5 facing the support shaft region SS. The through holes 5C of the bearing support area BS are connected to the through holes 1F formed in the main shaft 1, and the through holes 1F are connected to the through holes 3A, 4A formed in the inner rings of the bearings 3, 4. The through hole 5C is provided with the throttle valve 20 shown in FIG.

The throttle valve 20 has a bearing support region BS.
In each of the through holes 5C. The structure is such that the umbrella-shaped valve body 21 is loosely fitted into the valve hole body 22 in which the through hole 5C is expanded in an umbrella shape, and the valve body 21 is pushed back toward the center side by the spring 23 pressed into the step hole 22A. Seat 2 screwed to 5C
It is accepted by 4. In this state (when the spindle is stopped), the clearance between the through hole 21A opened in the center of the valve body 21 and the tapered surface 21B of the valve body 21 and the tapered surface 22B of the valve hole body 22 is widened to maximize lubrication. The cooling lubricant C for cooling can be sent to the maximum extent. When the main shaft 1 rotates, the valve body 2 is pushed back toward the center by the spring 23.
1 causes the tapered surface 21B to approach the tapered surface 22B of the valve hole body 22 against the elastic force of the spring 23 due to the generation of centrifugal force due to its own weight, and finally closes as shown in FIG. In this state (during high-speed rotation of the main shaft), the through hole 5C is only the through hole 21A opened at the center of the throttle valve 20.
FIG. 6 shows the relationship between the rotational speed of the main shaft and the amount Q1 of lubricating oil supplied to the bearing.

On the other hand, the through holes 5D ...
Is connected to the hole wall 1E, which is the inner peripheral surface of the main shaft 1,
A circulation path is formed such that the cooling lubricating liquid C is sent from the inner peripheral surface 1E to the tail end side of the spindle. In the through hole 5D,
The control valve 30 shown in FIG. 3 is provided. The control valve 30
Are respectively provided in the through holes 5D of the support shaft region SS. The configuration is the valve hole body 32 in which the through hole 5D is expanded in a dish shape.
The disc-shaped valve body 33 is loosely fitted in the through hole 5D, and the valve body 33 pushed back toward the center side by the spring 34 pressed into the through hole 5D is received by the seat body 35 screwed into the through hole 5D. In this state (when the spindle is stopped), the through hole 3 opened in the center of the valve body 33.
3A or the tapered surface 33B of the valve body 33 and the tapered surface 32B of the valve hole body 32 can be closed and throttled, and the cooling lubricating liquid C for cooling can be sent to the minimum. Then, when the main shaft 1 rotates, the valve body 33 pushed back toward the center by the spring 34 resists the elastic force of the spring 34 due to the generation of centrifugal force due to its own weight, so that the valve face body 32 has the tapered surface 33B. It is separated from the taper surface 32B of No. 3 and finally fully opened as shown in FIG. In this state (during high-speed rotation of the main shaft), the through hole 5D includes the through hole 30A opened in the central portion of the control valve 30, the tapered surface 33B of the valve body 33, and the tapered surface 3 of the valve hole body 32.
It is due to the gap with 2B. FIG. 6 shows the relationship between the spindle rotation speed and the coolant supply amount Q2 to the spindle.

The main spindle lubrication cooling device according to the present invention is constructed as described above and operates as follows. First, a part of the cooling lubricating liquid C that has flowed into the annular space 1D of the main shaft 1 is subjected to underrace lubrication of the bearings 2 and 3 arranged in the bearing support region BS so that the through hole 5 of the separator cylinder 5 can be used.
From the throttle valve 20 provided in C to the inner peripheral surface 1E of the main shaft. Here, the cooling lubricant C reaches the through holes 3A, 4A formed in the inner rings of the bearings 3, 4 from the front and rear through holes 1F while cooling the main shaft of the bearing support region BS. As a result, a part of the cooling lubricating liquid C carries out underrace lubrication of the bearings 3 and 4. The lubricating liquid C after underrace lubrication is
It is discharged to the outside from the drain passage on the frame side of the main shaft fixing machine.

Underrace lubrication of the bearings 3 and 4 is such that when the main shaft 1 is stopped and the main shaft 1 is rotating at a low speed, as shown in FIG.
0 indicates a fully open state, and the cooling lubricant C passing therethrough becomes maximum. Then, when the main shaft 1 rotates, the valve body 21 pushed back toward the center by the spring 23 generates a centrifugal force due to its own weight and resists the elastic force of the spring 23 to form the tapered surface 2.
1B is brought close to the tapered surface 22B of the valve hole body 22 and finally closed as shown in FIG. This state (when the spindle rotates at high speed)
5C, only the through hole 21A opened in the center of the throttle valve 20 is restricted. Therefore, the relationship between the rotational speed of the main shaft and the lubricating oil supply amount Q1 to the bearing is controlled under the inverse proportional control as shown in FIG. 6, and the excessive lubricating oil supply amount Q1 does not occur when the main shaft rotates at high speed. Therefore, the bearings 3 and 4 do not generate heat and underrace lubrication of the bearings 3 and 4 is ideally performed.

On the other hand, the cooling lubricating liquid C is also supplied to the control valve 30 provided in each through hole 5D of the support shaft region SS. Here, the cooling lubricating liquid C whose flow rate is controlled by the flow cross-sectional area of each control valve 30 is supplied to the inner peripheral surface of the main spindle 1, and the main spindle is cooled while being sent from the inner peripheral surface 1E to the tail end side of the main spindle. This relationship is shown in FIGS. That is, the cooling lubricant C is
When the main shaft 1 is stopped and rotates at low speed, the control valve 30 provided in the through hole 5D opens the through hole 33A in the center of the valve body 33, the tapered surface 33B of the valve body 33 and the tapered surface 32 of the valve hole body 32.
The clearance with B is closed and squeezed, and the cooling lubricating liquid C for cooling is squeezed to the minimum and sent.

When the main shaft 1 rotates, the valve body 33 pushed back toward the center by the spring 34 acts on the tapered surface 33B against the elastic force of the spring 34 due to the centrifugal force generated by its own weight. The hole body 32 is separated from the tapered surface 32B and finally fully opened as shown in FIG. In this state (during high-speed rotation of the main shaft), the through hole 5D includes the through hole 30A opened in the central portion of the control valve 30, the tapered surface 33B of the valve body 33, and the valve hole body 3.
This is due to the gap between the second tapered surface 32B and the cooling liquid supply amount Q2 is maximized. The relationship is shown in FIG. 6 so that the coolant supply amount Q2 to the spindle 1 increases proportionally to the spindle rotation speed. Therefore, the cooling action of the spindle 1 that increases the amount of heat generation in proportion to the spindle rotation speed is effectively performed.

The present invention is not limited to the above-mentioned embodiment, and the design of the main structure can be changed. For example, the through hole 5 of the separator tube 5
C, 5D and through hole 1F opened in the main shaft 1 and bearing 3,
Change the number of the through holes 3A and 4A of 4 and the cross-sectional area thereof appropriately. Furthermore, a bearing support region BS and a support shaft region SS of the main shaft are provided in an annular space between the drawing bar inserted through the main shaft hole and the wall of the main shaft hole, and the throttle valve 20 and the control valve 30 are provided side by side. However, the bearing supporting area BS for lubricating only the bearings 3 and 4 and the throttle valve 20 may be provided. On the contrary, the structure may be such that only the support shaft region SS for cooling only the main shaft and the control valve 30 are provided.

[0020]

According to the first aspect of the present invention, a throttle valve is provided in a through hole formed in the cylinder wall of the separator cylinder facing the bearing support region of the main shaft, and the lubricating oil fluid is sent to the throttle valve of the separator cylinder. , This lubricating fluid is supplied from the throttle valve of the separator cylinder through the through hole of the bearing support region and the through hole of the main shaft to the through hole of the inner ring of the bearing. It has the effect of simply lubricating and cooling. And, in addition to increasing the lubrication flow rate in the section from the stop of the spindle to the low speed rotation range by the action of the throttle valve,
The higher the spindle speed, the more the lubricating flow is reduced,
It has an effect of rationally suppressing heat generation by eliminating an excessive lubricating flow rate in the bearing portion.

Further, according to the second aspect of the present invention, the cooling fluid sent from the control valve in the support shaft region into the inner peripheral surface of the main shaft has an effect of cooling the main shaft from the inner peripheral wall thereof. The control valve acts to reduce the amount of lubricating cooling in the section from the stop of the main spindle to the low speed rotation range, and to increase the amount of lubricating cooling as the main spindle rotates at higher speed. There is an effect that it increases in proportion to the ideal cooling characteristics.

According to claim 3 of the present invention, the throttle valve is in a fully opened state in which the valve body is opened to the maximum by the elastic force of the spring when the main shaft is stopped and rotated at low speed, and when the main shaft rotates,
Since the valve body pushed back toward the center by the spring counteracts the elastic force of the spring due to the centrifugal force generated by its own weight, the taper surface approaches the taper surface of the valve hole body and finally closes. The number of revolutions and the amount of lubricating oil supplied to the bearing are controlled by a simple structure under the control of inverse proportion, and the amount of lubricating oil supplied does not become excessive when the spindle rotates at high speed. The effect of ideally performing underrace lubrication is exhibited.

Further, according to claim 4 of the present invention, the control valve exhibits a fully closed state of the valve body due to the elastic force of the spring when the main shaft is stopped and rotates at low speed, and when the main shaft rotates, the control valve causes the central side to move. Since the valve body pushed to the side resists the elastic force of the spring due to the generation of centrifugal force due to its own weight, the tapered surface is moved away from the tapered surface of the valve hole body and finally fully opened. The amount of cooling liquid supplied to the spindle is controlled by a simple structure under proportional control, and the maximum amount of cooling liquid is supplied when the spindle rotates at high speed, and the spindle does not generate heat. Is demonstrated.

[Brief description of drawings]

FIG. 1 is an overall cross-sectional view showing underrace lubrication of a spindle and the like according to the present invention.

FIG. 2 is an enlarged sectional view of the first embodiment according to the present invention.

FIG. 3 is a sectional view of an essential part of a second embodiment according to the present invention.

FIG. 4 is an enlarged sectional view showing the operation of the first embodiment according to the present invention.

FIG. 5 is an enlarged cross-sectional view showing the operation of the second embodiment according to the present invention.

FIG. 6 is an explanatory diagram showing a lubricating cooling amount and a spindle rotation speed according to the present invention.

[Explanation of symbols]

1 spindle 1E spindle tail end hole 3,4 bearing 3A, 4A inner ring 2 drawing bar 1F, 3A, 4A, 5C, 5D through hole 5 separator cylinder BS bearing support area SS support shaft area C cooling lubricant 20 throttle valve 21, 33 valve body 21A, 33A through hole 21B, 22B, 32B, 33B tapered surface 22,32 valve hole body 23,34 spring Q1 lubricating oil supply amount 30 control valve Q2 cooling liquid supply amount

Claims (4)

[Claims] 1. A separator cylinder for bearing a bearing support area of a main shaft is provided inside a main shaft hole into which lubricating oil is fed from the tail end side of the main shaft, the hole wall in an annular space obtained by inserting a drawing bar. A first through hole for feeding lubricating oil is provided in a cylinder wall of the separator cylinder facing the bearing supporting area, and the first through hole is connected to a second through hole formed in the main shaft of the bearing supporting area. The second through hole formed in the main shaft is connected to the third through hole formed in the inner ring of each bearing, and the throttle valve is arranged in the first through hole of the separator cylinder.
This throttle valve is a lubrication cooling device for a spindle, characterized in that the lubrication flow rate is released in the section from the stop of the spindle to the low speed rotation range, and the lubrication flow rate is throttled as the spindle rotates at a higher speed. 2. A separator cylinder for supporting a supporting shaft region of a main shaft is provided in a hole wall in an annular space obtained by inserting a drawing bar in the main shaft hole into which lubricating oil is fed from the tail end side of the main shaft. A fourth through hole for feeding the lubricating coolant to the cylinder wall of the separator cylinder facing the support shaft region, the fourth through hole communicating with the main shaft of the support shaft region, and the fourth through hole. A control valve is installed in the control valve.The control valve throttles the lubricating cooling amount in the section from the stop of the main spindle to the low speed rotation range, and the lubricating cooling amount of the main spindle is increased as the main spindle rotates at higher speed. apparatus. 3. The lubrication cooling device for a spindle according to claim 1, wherein the throttle valve is in a fully opened state in which the valve element is fully opened by the elastic force of the spring when the spindle is stopped and rotated at a low speed, and the spindle rotates. Then, the valve element pushed back toward the center by the spring,
A lubricating and cooling device for a main shaft, characterized in that a tapered surface is made to approach a tapered surface of a valve hole body and finally closed against a resilient force of a spring due to generation of centrifugal force due to its own weight. 4. The lubrication cooling device for a spindle according to claim 2, wherein the control valve exhibits a fully closed state of the valve body due to the elastic force of the spring when the spindle is stopped and rotates at a low speed, and when the spindle rotates, the control valve is operated by the spring. The main shaft is characterized in that the valve body pushed toward the center side moves the tapered surface away from the taper surface of the valve hole body and fully opens against the elastic force of the spring due to the generation of centrifugal force due to its own weight. Lubricating cooling device.