JP2003083343A - Main shaft device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a main shaft device which can maintain stable rotational performance of a shaft by ensuring good lubricating performance, can reduce noise and can save driving energy of a shaft, even in the case of generating a high speed. SOLUTION: Lubrication of a rolling bearing 5 rotatably supporting a shaft 3 of a main shaft device 100 is performed by directly injecting a fine amount of lubricating oil from a lubricating oil nozzle 13 mounted in a housing 7, simultaneously formed with a base end side lubricating oil route 13b and a tip end side lubricating oil route 13c in the lubricating oil nozzle 13 so as to make suction of lubricating oil caused by a flow of air due to rotation of the shaft 3 less than a delivery amount of one shot.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle device having a lubricating oil supply mechanism for supplying lubricating oil to a bearing in which an inner ring and an outer ring are relatively rotatable via rolling elements. The present invention relates to an improvement for improving the lubrication performance of the bearing, which is essential for improving the rotation performance and durability of the shaft.

[0002]

2. Description of the Related Art In various industrial machines such as machine tools, a shaft, a bearing having an inner ring inner diameter surface fitted to the shaft, a housing having an outer ring outer diameter surface of the bearing fitted, an inner ring and an outer ring. There is used a main shaft device having a lubricating oil supply mechanism that supplies lubricating oil to a bearing that is relatively rotatable via rolling elements.

In the case of a conventional spindle device used in a machine tool or the like, the lubricating oil supply mechanism to be mounted can be roughly classified into an oil mist system, an oil air system, a jet system and the like.

The oil mist type lubricating oil supply mechanism comprises an oil tank, a pump, a plunger, a voltage divider, a compressed air source, an electromagnetic valve, and a nozzle, and makes the lubricating oil into a fine mist and then compresses it. It is configured to be conveyed through air piping by air and to be jetted toward the inside of the bearing.

An oil-air type lubricating oil supply mechanism comprises an oil tank, a pump, a distributor, a compressed air source, a plunger and a nozzle, and a lubricating oil droplet (a fixed amount is adjusted by a mechanical mechanism of the plunger). 0.01-0.03m
1) is discharged into the air pipe, is carried to the nozzle by air, and is jetted toward the inside of the bearing.

The jet type lubricating oil supply mechanism does not use a compressed air source, but makes the lubricating oil high pressure by a high pressure pump, and jets the lubricating oil at high speed from a nozzle having a narrow discharge diameter toward the inside of the bearing. .

[0007]

By the way, as a recent tendency, there is a strong demand for higher speed in a spindle device used for machine tools and the like. However, the above-described conventional lubricating oil supply mechanisms have the following problems with respect to the speedup of the spindle device.

Generally, when the rotation speed of the shaft of the main spindle device is increased, an air curtain is formed on the outer circumference of the shaft by a layer of air contacting the outer peripheral surface of the shaft. However, in the case of an oil mist type or oil air type lubricating oil supply mechanism, the lubricating oil particles contained in compressed air and injected into the bearing are small, and the discharge speed is small, so the inertial mass of the lubricating oil particles is very small. become. Therefore, during high speed operation of the shaft, the injection of lubricating oil particles is blocked by the air curtain formed on the outer periphery of the shaft,
Lubricating oil could not reach the inside of the bearing, which could cause problems such as seizure of the bearing due to insufficient lubrication.

Further, in the case of an oil mist type or oil air type lubricating oil supply mechanism, when a large amount of compressed air is injected into the bearing and sheared by the rolling elements inside the bearing,
Wind noise is generated, and this wind noise may cause noise. In addition, in the case of an oil mist type or oil air type lubricating oil supply mechanism, a relatively large compressed air source is required because a large flow rate of compressed air is used to convey and inject lubricating oil particles.
There is also a problem that the compressed air source causes an increase in size of the device.

On the other hand, in the case of the jet type lubricating oil supply mechanism, since the high pressure lubricating oil is directly injected to the bearing, the lubricating oil flying toward the bearing as compared with the above-mentioned oil mist type or oil air type. Large grains and large inertial mass. Therefore, it is less likely that the injection of lubricating oil particles will be interrupted by the air curtain formed on the outer periphery of the shaft during high-speed operation of the shaft. However, it is extremely difficult to limit the amount of lubricating oil supplied to a very small amount or a very small amount, and the excessively supplied lubricating oil causes stirring resistance in the bearing, increasing the rotational friction of the bearing, and as a result, There is a possibility of causing a problem of temperature rise and a problem of increased loss of drive torque of the shaft.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to prevent supply of lubricating oil to a bearing by an air curtain formed on the outer circumference of the shaft during high speed operation of the shaft. In addition, it is possible to prevent the generation of noise due to wind noise, and at the same time avoid the problems of bearing temperature increase and driving torque loss increase due to excessive supply of lubricating oil. Even if it is realized, it is an object of the present invention to provide a spindle device that can maintain stable rotation performance of a shaft by ensuring good lubrication performance, reduce noise, and save drive energy of the shaft.

[0012]

In order to achieve the above object, a spindle device according to the present invention has a shaft and a bearing having an inner ring inner diameter surface fitted to the shaft, as described in claim 1. A spindle including a housing in which the outer ring outer diameter surface of the bearing is fitted, and a lubricating oil supply mechanism that supplies lubricating oil to the bearing in which the inner ring and the outer ring are relatively rotatable via rolling elements. In the device, the lubricating oil supply mechanism includes a lubricating oil nozzle that injects lubricating oil to the bearing, and a micro-lubrication device that supplies a small amount of lubricating oil to the lubrication oil nozzle, and the bearing has a discharge speed. In the range of 10 to 100 m / sec, and the discharge amount is 0.0005 to 0.01 per shot.
A small amount of lubricating oil in the range of ml is intermittently injected and supplied from the lubricating oil nozzle, and the lubricating oil nozzle serves as a lubricating oil path for guiding the lubricating oil to the discharge port at the tip, along the axial direction of the nozzle body. And a base end side lubricating oil passage which is bored linearly, and a tip end of the base end side lubricating oil passage and the discharge port are communicated with each other linearly along the discharge direction of the lubricant oil. A tip side lubricating oil path, and the volume of the tip side lubricating oil path is set to be less than the discharge amount per one shot by the lubricating oil nozzle, and the orientation of the base side lubricating oil path is the center thereof. The included angle θ between the axis and the horizontal is 1
It is characterized in that it is set to fall within the range of 0 to 170 °.

In the spindle device constructed as described above, the direct injection type in which the lubricating oil is directly injected to the rolling bearing without using compressed air is injected to the bearing as compared with the conventional oil mist type or oil air type. The lubricating oil particles to be discharged are large, and the discharge speed is large in the range of 10 to 100 m / sec. Therefore, the inertial mass of the lubricating oil particles injected to the bearing is large, and the lubricating oil particles injected from the lubricating oil nozzle are
During high speed operation of the shaft, the air curtain formed on the outer periphery of the shaft can easily be penetrated to reach a predetermined portion of the bearing.

Further, unlike the case of the oil mist system or the oil air system, the compressed air is not used for the injection of the lubricating oil, and the compressed air does not collide with the rolling elements of the bearing, so that no wind noise is generated. In addition, the amount of lubricating oil supplied is very small or extremely small with the discharge amount and discharge speed limited, so there is no excessive supply of lubricating oil compared to the case of the conventional jet system It is possible to avoid problems such as an increase in bearing temperature and an increase in driving torque loss.

Further, since the lubricating oil to be injected and supplied is very small,
As the pump means provided in the lubricating oil supply mechanism, a small one that discharges a small amount of lubricating oil can be used as compared with the conventional jet method.

Further, in the main spindle device, normally, the airflow generated around the shafts and bearings due to the rotation of the shafts and bearings acts on the discharge port of the lubricating oil nozzle to remove the lubricating oil remaining in the nozzle. Sucking occurs. Then, instead of the sucked lubricating oil, air enters the nozzle. The phenomenon of sucking out the lubricating oil in the nozzle due to the air flow around the nozzle becomes stronger as the rotational speed of the shaft is increased, and when a certain amount of air or more enters the nozzle, the compressibility of the air causes
There is a possibility of causing a serious obstacle that makes it impossible to discharge the lubricating oil.
Since the lubricating oil supply mechanism of the present invention discharges a small amount of oil at high speed, the oil flow path from the pipe downstream of the pump to the nozzle discharge port must be completely filled with oil. Even if the amount of air invading by sucking out the lubricating oil is very small, that air will form bubbles and will flow backwards inside the nozzle to the pump side.
If it remains in a deep position inside the nozzle or in a pipe connected to the nozzle, etc., due to the compressibility of the remaining bubbles,
The discharge pressure may fluctuate or the discharge may be disabled. However, in the above configuration, the lubricating oil passage in the lubricating oil nozzle is provided with the leading end side lubricating oil passage that receives the action of sucking the lubricating oil by the air flow near the discharge port and the proximal end lubrication inside the nozzle that is difficult to receive the sucking action. An oil passage is provided, and the inner volume of the tip side lubricating oil passage is set to be less than the discharge amount of one shot. Therefore, even if all the lubricating oil in the tip side lubricating oil passage is sucked out by the external air flow, the next one shot of lubricating oil discharge has a quantity equal to or more than the sucked lubricating oil,
At the same time that the air that has entered through the discharge port can be discharged at the time of suction, the lubricating oil having the difference between the original discharge amount and the suction amount can be injected to the bearing, and there is no serious obstacle to unlubrication. Moreover, when the equipment angle θ of the base end side lubricating oil passage is set to 10 to 170 ° with respect to the horizontal, the intersection of the tip end side lubricating oil passage and the tip end side lubricating oil passage is sucked into the inside of the nozzle. Since the air bubbles that enter air will not be able to pass through the bent portion, the air bubbles that have invaded by suction do not flow backward in the proximal lubrication oil passage beyond the tip side lubricating oil passage in the nozzle. It is possible to prevent the inconvenience that air bubbles are mixed and remain in a deep position in the nozzle or a pipe connected to the nozzle.

Further, according to a second aspect of the present invention, there is provided a spindle device, a shaft, a bearing having an inner ring inner diameter surface fitted to the shaft, and a housing having an outer ring outer diameter surface fitted to the shaft. ,
In a spindle device including a lubricating oil supply mechanism that supplies lubricating oil to the bearing in which the inner ring and the outer ring are relatively rotatable via rolling elements, the lubricating oil supply mechanism is
The bearing is provided with a lubricating oil nozzle for injecting lubricating oil to the bearing, and a small amount lubrication device for supplying a small amount of lubricating oil to the lubricating oil nozzle, and the bearing has a discharge speed of 10 to 100 m / sec.
And the discharge amount is 0.0005 per shot
A small amount of lubricating oil in the range of 0.01 ml is intermittently injected and supplied from the lubricating oil nozzle, and the lubricating oil nozzle is
As a lubricating oil path for guiding the lubricating oil to the discharge port at the tip, a tip side lubricating oil path having a length of 3 mm or more, which is linearly bored along the lubricating oil discharge direction, is provided, and the tip side lubricating oil path is provided. The volume from the discharge port up to 3 mm is set to be less than the discharge amount per shot by the lubricating oil nozzle,
Further, the orientation of the tip side lubricating oil passage is set so that the included angle φ between the central axis and the horizontal line falls within the range of 20 to 160 °.

The spindle device configured as described above is common with the spindle device according to claim 1 in that it is a direct injection type in which a very small amount or a very small amount of lubricating oil is directly injected to the bearing without using compressed air. However, in this respect, it is possible to obtain the same operation and effect as the spindle device according to the first aspect. Further, the influence of suction by the external air flow generated near the discharge port of the lubricating oil nozzle due to the rotation of the shaft and the bearing can be mitigated / controlled by adjusting the included angle φ formed by the front end side lubricating oil passage being horizontal. Then, as described above, when the included angle φ formed by the front end side lubricating oil passage being horizontal is set in the range of 20 to 160 °, the influence of suction is set within a range of about 3 mm from the discharge port at the end of the front end side lubricating oil passage. Can be restricted, and also
By setting the volume in the path from the discharge port to 3 mm to be less than the discharge amount per shot, the suction amount of the lubricant oil in the lubricant oil nozzle by the external air flow can be reduced to less than the discharge amount of one shot from the lubricant oil nozzle. It is possible to restrict and prevent the air bubbles that have invaded by suction from flowing backward in the base end side lubricant oil path beyond the tip side lubricant oil path in the nozzle.

Further, in the spindle device of the present invention, as described in claim 3, a shaft, a bearing having an inner ring inner diameter surface fitted to the shaft, and a housing having an outer ring outer diameter surface fitted to the bearing. ,
In a spindle device including a lubricating oil supply mechanism that supplies lubricating oil to the bearing in which the inner ring and the outer ring are relatively rotatable via rolling elements, the lubricating oil supply mechanism is
The bearing is provided with a lubricating oil nozzle for injecting lubricating oil to the bearing, and a small amount lubrication device for supplying a small amount of lubricating oil to the lubricating oil nozzle, and the bearing has a discharge speed of 10 to 100 m / sec.
And the discharge amount is 0.0005 per shot
A small amount of lubricating oil in the range of 0.01 ml is intermittently injected and supplied from the lubricating oil nozzle, and the lubricating oil nozzle is
A check valve for preventing backflow is provided at a position where the volume from the discharge port is less than the discharge amount per shot by the lubricant oil nozzle in the middle of the lubricant oil path for guiding the lubricant oil to the discharge port at the tip. It is characterized by.

The spindle device configured as described above is common with the spindle device according to claim 1 in that it is of a direct injection type that directly injects a very small amount or a very small amount of lubricating oil to the bearing without using compressed air. However, in this respect, it is possible to obtain the same operation and effect as the spindle device according to the first aspect. In addition, there is a swinging type spindle device in which the angle of the spindle can be arbitrarily adjusted in the above-mentioned spindle device subject to the direct injection type lubrication, and when the angle of the spindle is changed, the lubricating oil nozzle Also changes the equipment posture. Therefore, by changing the angle of the main shaft, the included angle θ between the base end side lubricating oil path and the horizontal direction described above
Or the included angle φ between the tip side lubricating oil path and the horizontal direction is outside the initially set range, and setting these angles θ and φ alone
It may not be possible to suppress the influence of the external air flow in the vicinity of the discharge port as originally set. However, as described above, if the check valve is provided in the middle of the lubricating oil path of the lubricating oil nozzle, the action of the check valve limits the amount of lubricating oil that is sucked out, and at the same time, it intrudes by suction. It is possible to prevent the generated air bubbles from flowing back through the lubricating oil passage in the nozzle.

Further, in the spindle device of the present invention, as described in claim 4, the shaft, the plurality of bearings having the inner ring inner diameter surface fitted to the shaft, and the outer ring outer diameter surface of the bearing fitted to each other. In a main spindle device including a housing, a lubricating oil supply mechanism that supplies lubricating oil to the plurality of bearings in which the inner ring and the outer ring are relatively rotatable via rolling elements, the lubricating oil supply mechanism includes: A plurality of lubricating oil nozzles for respectively injecting lubricating oil to each of the bearings provided, wherein the plurality of lubricating oil nozzles are any of the nozzles according to any one of claims 1 to 3. To do.

In the spindle device constructed as described above, even if any of the lubricating oil nozzles is selected due to the mounting space or the like, all of the lubricating oil nozzles are provided with the lubricating oil from the discharge port due to the external air flow. The sucking action can be reduced and good lubricity can be maintained.

Further, in the spindle device of the present invention, the equipment direction of the lubricating oil nozzle is set so that the base end side lubricating oil path and the tip end side lubricating oil path are continuous in a straight line. It is a thing.

In the spindle device configured as described above, when manufacturing the lubricating oil nozzle, the base end side lubricating oil path and the tip end side lubricating oil path can be machined at one time, and the machining process can be reduced. be able to.

Further, in the spindle device of the present invention, the shaft, the bearing having the inner ring inner diameter surface fitted to the shaft, the housing having the outer ring outer diameter surface of the bearing fitted thereto, and the inner ring and the outer ring rolling. In a main spindle device including a lubricating oil supply mechanism that supplies lubricating oil to the bearing that is relatively rotatable via a moving body, the lubricating oil supply mechanism includes a lubricating oil nozzle that injects lubricating oil to the bearing. A minute amount lubrication device for supplying a minute amount of lubricating oil to the lubricating oil nozzle, and a discharge speed in the range of 10 to 100 m / sec and a discharge amount of 1 to the bearing.
A small amount of lubricating oil in the range of 0.0005 to 0.01 ml per shot is intermittently injected and supplied from the lubricating oil nozzle, and a pair of bearings are axially separated from each other on the shaft so that the contact angles thereof are different from each other. The lubricating oil nozzle that injects the lubricating oil into one of the pair of bearings when they are arranged so as to face each other in the opposite direction is the lubricating oil passage that guides the lubricating oil to the discharge port at the tip. The base end side lubricating oil passage linearly bored along the axial direction of the base end side lubricating oil passage and the end of the base end side lubricating oil passage and the discharge port are communicated linearly along the discharge direction of the lubricating oil. And a volume of the tip side lubricating oil passage is set to be less than a discharge amount per one shot by the lubrication oil nozzle, and the base end side lubricating oil passage is further provided. The direction of the center axis and the horizon The lubricating oil nozzle, which is set so that the included angle θ falls within the range of 10 to 170 ° and injects lubricating oil to the other of the pair of bearings, serves as a lubricating oil path for guiding the lubricating oil to the discharge port at the tip. , A base end side lubricating oil passage linearly formed along the axial direction of the nozzle body, and a tip end of the base end side lubricating oil passage and the discharge port so as to communicate with each other in the discharge direction of the lubricant oil. The length of the straight hole is 3
mm or more, and the volume of the tip side lubricating oil path from the discharge port to 3 mm is set to be less than the discharge amount per one shot by the lubricant oil nozzle. It is characterized in that the direction of the lubricating oil passage is set so that the included angle φ between the central axis and the horizontal line falls within the range of 20 to 160 °.

In the main spindle device, when a lubricating oil nozzle for supplying lubricating oil to each bearing is provided between a pair of opposed bearings, the positions of the lubricating oil nozzles are determined according to the installation space and other factors. The lubricant nozzle of
In some cases, the angle φ formed by the front end side lubricating oil path with the horizontal direction cannot be set to an appropriate range that reduces the sucking action by the external air flow. However, in such a case, in the spindle device having the above-described configuration, the lubricating oil nozzle in which the angle φ formed by the leading end side lubricating oil path with the horizontal direction cannot be set to an appropriate range has a proximal end side lubricating oil path. Angle with the direction θ
By setting the value in the appropriate range, it is sufficient to reduce the influence of suction from the external air flow in the vicinity of the discharge port on both lubricating oil nozzles and to maintain good lubricating performance. Also in the above, the action of sucking the lubricating oil from the discharge port by the external air flow can be reduced.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a spindle device according to the present invention will be described in detail below with reference to the drawings. Figure 1
[FIG. 3] shows a first embodiment of a spindle device according to the present invention. The spindle device 100 according to the first embodiment
Is for a machine tool, is a main shaft for rotating a workpiece or a tool at high speed, a rolling bearing 5 in which the inner diameter surface of an inner ring 5a is fitted to the shaft 3, and an outer diameter of an outer ring 5b of the rolling bearing 5. The housing 7 is fitted with its surface, and a lubricating oil supply mechanism 11 is provided for supplying lubricating oil to the rolling bearing 5 in which the inner ring 5a and the outer ring 5b are relatively rotatable via the rolling elements 5c.

In the case of the present embodiment, the shaft 3 is installed with its central axis oriented horizontally. In addition, the rolling bearing 5
Is an angular contact ball bearing in which the rolling elements 5c are spherical.

The lubricating oil supply mechanism 11 includes a lubricating oil nozzle 13 for injecting lubricating oil to the rolling bearing 5 and a lubricating oil nozzle 13.
A microlubrication device (not shown) for supplying a small amount of lubrication oil to the lubricating oil, and a pipe 15 (see FIG. 2) for guiding the lubrication oil discharged from the microlubrication device to the lubrication oil nozzle 13 are provided in the rolling bearing 5. Discharge speed is in the range of 10 to 100 m / sec,
Moreover, the discharge amount is 0.0005 to 0.0 per shot.
A small amount of lubricating oil in the range of 1 ml is intermittently injected and supplied from the lubricating oil nozzle 13.

In the case of the present embodiment, the micro-lubrication device (not shown) realizes the supply of the lubricating oil at the above-mentioned discharge speed and discharge amount by the reciprocating pump mechanism which drives the piston by the expansion / contraction operation of the giant magnetostrictive element. To do.

As shown in FIGS. 2 and 3, the lubricating oil nozzle 13 includes a nozzle body 21 fitted and held in the housing 7,
The nozzle tip 23 is embedded in and fixed to the tip of the nozzle body 21 to provide the discharge port 13a. A pipe 15 for guiding the lubricating oil discharged by a microlubrication device (not shown) is connected to the base end side of the nozzle body 21 via a pipe joint 25. The connecting portion of the pipe joint 25 is provided on the rear end surface of the nozzle body 21 as shown in FIG. 2, and is also provided on the side surface of the nozzle body 21, and is sealed by a plug when not in use. The connecting portion to be used may be selected according to the mounting space in the housing.

In the lubricating oil nozzle 13 according to the present embodiment, the lubricating oil passage for guiding the lubricating oil to the discharge port 13a at the tip is a proximal end lubricating oil bored linearly along the axial direction of the nozzle body 21. Path 13b and this proximal side lubricating oil path 13b
End side lubricating oil passage 1 linearly formed along the discharging direction of the lubricating oil so as to connect the tip of the
3c and. Then, the tip side lubricating oil passage 13c
So that its volume is less than the discharge amount per shot by the lubricating oil nozzle 13 concerned.
And the length L1 of the tip side lubricating oil passage 13c are set.

Further, in the case of this embodiment, as shown in FIG. 2, the orientation of the base end side lubricating oil passage 13b is in the range of an included angle θ between the central axis and the horizontal line of 10 to 170 °. It is set to enter. Further, the tip side lubricating oil passage 13c
Sets the length L1 to 3 mm or more, and
The volume from 3a to 3 mm is set to be less than the discharge amount per shot by the lubricating oil nozzle 13. Further, the orientation of the base end side lubricating oil passage 13b is set so that the included angle φ between the central axis and the horizontal line falls within the range of 20 to 160 °.

The inventor of the present application has found that the lubricating oil nozzle 1 shown in FIGS.
In Fig. 3, it was observed that air bubbles flow backward through the lubricating oil path in the nozzle under the condition that the state of the wind inside the main shaft is approximated. For the observation, the lubricating oil nozzle used was made of acrylic and transparent, and the backflow of bubbles could be visually observed. However, only the nozzle tip was made of brass in order to maintain the same machining accuracy as the actual nozzle. Compressed air, which is generated with the rotation of the bearing and acts as an air curtain to simulate the air flow that impairs the lubrication performance, is jetted almost at right angles to the discharge direction of the lubricating oil nozzle, and the direction of the wind in the main shaft Was approximated to. In addition, the compressed air from the position about 8 mm away from the discharge port of the lubricating oil nozzle,
It was jetted from an air nozzle having a nozzle diameter of 1.6 mm at a pressure of 0.5 MPa. The ejection speed of the compressed air of 0.5 MPa from the air nozzle is about 300 m / s when calculated assuming isentropic change, which is faster than the peripheral speed of the rotating body of the spindle (about 150 m / s at high speed). , It is a test under severe conditions compared to the actual conditions.

Under this condition, backflow of air easily occurs,
Immediately after the air nozzle injection, backflow started from the lubricating oil nozzle discharge port. Backflow of air does not easily occur with air injection of less than 0.1 PMa, which is close to the original usage conditions, but it has been confirmed that a slight amount of air bubbles backflow when pressure changes such as vibrating an object near the discharge port. It was Even inside the actual spindle, it is considered that pressure fluctuations occur due to the passage of balls and the like, causing backflow of bubbles. In this test, it is considered that the condition in which the backflow of bubbles stops is a sufficient condition in which the backflow of air does not proceed even in the actual spindle device.

In addition, as another condition, the degree of backflow of air varies depending on the design of the nozzle tip.
That is, in the nozzle tip shown in FIG. 4, if the nozzle length P at the tip end portion is sufficiently long, backflow will not occur, but if the nozzle length P is increased, the pressure loss increases and the nozzle diameter 0 Since it is difficult to make a small hole of about 1 mm deep, the nozzle length is usually set to about 100 to 300% of the nozzle diameter. Considering that backflow of air may occur in this range. Chip design should be done.

In the spindle device 100 described above, a direct injection type in which lubricating oil is directly injected to the rolling bearing 5 without using compressed air is used, and compared with the conventional oil mist type or oil air type, the rolling bearing 5 is provided. The lubricating oil particles injected are large, and the discharge speed is also large in the range of 10 to 100 m / sec. Therefore, the inertial mass of the lubricating oil particles injected to the rolling bearing 5 is large, and the lubricating oil particles injected from the lubricating oil nozzle 13 easily form the air curtain formed on the outer periphery of the shaft 3 during high speed operation of the shaft 3. It can penetrate and reach a predetermined portion of the rolling bearing 5. Therefore, during high-speed operation of the shaft 3, the lubricating oil supply to the rolling bearing 5 is not hindered by the air curtain formed on the outer periphery of the shaft 3, and stable lubrication oil supply is achieved even during high-speed operation of the shaft 3. The rolling bearing 5 can be maintained in a good lubrication state.

Further, unlike the oil mist system or the oil air system, compressed air is not used for injecting the lubricating oil, and the compressed air does not collide with the rolling elements 5c of the rolling bearing 5 or the like, so that a wind noise is generated. Without doing so, it is possible to prevent generation of noise due to wind noise.

Further, since the lubricating oil to be supplied is a very small amount or an extremely small amount with the discharge amount and discharge speed limited, excess supply of the lubricating oil does not occur as compared with the case of the conventional jet system.
It is possible to avoid problems such as an increase in temperature of the rolling bearing 5 and an increase in driving torque loss due to excessive supply of lubricating oil.

Further, since the amount of lubricating oil to be injected and supplied is very small,
As the pump means provided in the lubricating oil supply mechanism 11, it is possible to use a small-sized pump that has a smaller amount of lubricating oil discharged as compared with the conventional jet method. By downsizing the pump means for lubricating oil and downsizing the compressed air source, it is possible to downsize the device and reduce the cost.

Further, in the main spindle device 100, normally, the air flow generated around the shaft 3 and the rolling bearing 5 by the rotation of the shaft 3 and the rolling bearing 5 is the discharge port 1 of the lubricating oil nozzle 13.
3a acts to suck out the lubricating oil remaining in the nozzle. Then, instead of the sucked lubricating oil, air enters the nozzle. The suction phenomenon of the lubricating oil in the nozzle due to the air flow around the nozzle becomes stronger as the rotational speed of the shaft 3 is increased, and when a certain amount of air or more enters the nozzle, the lubricating oil is compressed due to the compressibility of the air. There is a risk of causing a serious obstacle that makes it impossible to discharge the ink. In addition, even if the amount of invading air is a small amount, if the air becomes bubbles and flows backward in the nozzle to the pump side, and remains in a deep position in the nozzle or in pipes connected to the nozzle, etc., Due to the compressibility of the remaining bubbles, the discharge pressure may fluctuate or the discharge may become impossible.

However, in the present embodiment, the lubricating oil passage in the lubricating oil nozzle 13 is subjected to the action of sucking the lubricating oil by the air flow near the discharge port 13a, and the leading end side lubricating oil passage 13c.
And the proximal end side lubricating oil passage 13b inside the nozzle that is hard to receive the suction action, and the inner volume of the leading end side lubricating oil passage 13c is set to be less than the discharge amount of one shot. Therefore, even if all the lubricating oil in the tip-side lubricating oil passage 13c is sucked out by the external air flow, the next one shot of lubricating oil discharge has a larger amount than the sucked lubricating oil and is discharged at the time of sucking out. At the same time that the air that has entered through the outlet 13a can be discharged, the lubricating oil having a difference between the original discharge amount and the suction amount can be injected to the rolling bearing 5, and thus a serious obstacle such as unlubrication does not occur.

Further, according to the experiments conducted by the inventor of the present application, the behavior of bubbles caused by the air intruding from the discharge port 13a was confirmed by changing the equipment angle θ of the base end side lubricating oil passage 13b in various ways. There was found. That is, as shown in FIG. 5, a region s1 in which the equipment angle θ of the base end side lubricating oil passage 13b is 0 ° to 10 ° with respect to the horizontal direction, and 170 ° to 19 °.
In the 0 ° area s2 and the 350 ° to 360 ° area s3, air bubbles that have entered the tip side lubricating oil passage 13c are
There is a phenomenon of being pushed into the base end side lubricating oil passage 13b side. However, in the region s4 where θ is 10 ° to 170 °, a phenomenon was observed in which the progress of bubbles stopped at the intersection of the front end side lubricating oil passage 13c and the base end side lubricating oil passage 13b. Furthermore, θ is 1
In the region s5 of 90 ° to 350 °, the tip side lubricating oil passage 1
It was observed that the bubbles that reached the intersection of 3c and the base end side lubricating oil passage 13b were sequentially lifted in the base end side lubricating oil passage 13b by buoyancy.

Therefore, as in the present embodiment, the equipment angle θ of the base end side lubricating oil passage 13b is 10 to 17 with respect to the horizontal.
If it is set at 0 °, the intersection of the tip side lubricating oil passage 13c and the tip side lubricating oil passage 13c becomes a bent portion that air bubbles that enter the nozzle due to the suction action cannot pass. Air bubbles that have invaded by suction do not flow back into the proximal lubricating oil passage 13b beyond the distal lubricating oil passage 13c in the nozzle, and bubbles into a deep position in the nozzle or pipes connected to the nozzle. It is possible to prevent the inconvenience of being mixed and remaining.

At the intersection of the front end side lubricating oil passage 13c and the base end side lubricating oil passage 13b, if extra recesses x1 and x2 are formed by drilling in FIG. 6B, The invading air bubbles are easily caught by the recesses x1 and x2 and remain. Therefore, as shown in FIG. 6A, it is preferable to carefully process the intersection of the front end side lubricating oil passage 13c and the base end side lubricating oil passage 13b so that an unnecessary recess is not formed.

Further, the influence of sucking by the external air flow generated near the discharge port 13a of the lubricating oil nozzle 13 due to the rotation of the shaft 3 and the rolling bearing 5 is influenced by the tip side lubricating oil passage 13c.
Can be relaxed and regulated by adjusting the included angle φ that is horizontal. In the experiment by the inventor of the present application, as shown in FIG.
Angle φ of tip side lubricating oil passage 13c and tip side lubricating oil passage 1
A correlation was obtained with the length of the bubbles penetrating into 3c. From FIG. 7, when the included angle φ formed by the front end side lubricating oil passage 13c with the horizontal is set in the range of 20 to 160 ° as described above, the influence of suction is influenced by the discharge port 13a at the end of the front end side lubricating oil passage 13c. Can be limited to the range of about 3 mm,
In addition, by setting the volume in the path from the discharge port 13a to 3 mm to be less than the discharge amount per shot, the suction amount of the lubricant oil in the lubricant oil nozzle 13 by the external air flow can be set to one shot from the lubricant oil nozzle 13. It is possible to limit the discharge amount to less than the above, and to prevent the air bubbles that have invaded by suction from flowing back through the base side lubricating oil passage 13b beyond the tip side lubricating oil passage 13c in the nozzle.

Summarizing the above, the spindle device 10 of the present invention
At 0, stable rotation performance of the shaft 3 can be maintained by securing good lubrication performance even when the rotation speed of the shaft 3 is increased, and noise can be reduced by eliminating wind noise. . Furthermore, by preventing the accumulation of lubricating oil and the occurrence of excessive supply, it is possible to prevent an increase in stirring resistance on the rolling bearing 5, save drive energy for the shaft 3, and reduce the size of the drive source. The device can be made compact due to. Further, even if the lubricating oil in the lubricating oil nozzle 13 is sucked out by the air flow caused by the rotation of the shaft 3 and the rolling bearing 5, a serious obstacle such as inability to discharge is not caused by the sucking out of the lubricating oil. It is possible to improve the reliability of lubrication performance during high-speed operation without causing air bubbles mixed in the inside to flow backward in the nozzle and reduce discharge performance.

FIG. 8 shows a second embodiment of the lubricating oil nozzle used in the spindle device according to the present invention.
The lubricating oil nozzle 33 of the second embodiment can be installed in place of the lubricating oil nozzle 13 in the above-described spindle device 100. This lubricating oil nozzle 33 has a nozzle body 3 having a discharge port 33a at the tip thereof.
5 is embedded, and the lubricating oil is further discharged from the discharge port 33 at the tip.
As in the first embodiment, the base end side lubricating oil passage 33b and the tip end side lubricating oil passage 33c are provided as the lubricating oil passages leading to a.

However, in the present embodiment, a reverse flow is prevented at a position where the volume from the discharge port 13a is less than the discharge amount per shot by the lubricant oil nozzle 33 in the middle of the tip side lubricant oil passage 33c. A stop valve 37 is provided. In this check valve 37, the valve element 37a is spring 37 due to the pressure of the lubricating oil.
When the lubricating oil pressure does not act from the pump side by displacing in the direction of the arrow (a) against b, the valve body 37a is seated on the valve seat 37c by the urging force of the spring 37b, and is moved to the pump side. This is a structure for preventing backflow of air and invasion of air bubbles. In the case of the present embodiment, a lubricating oil filter 38 is provided at the intersection of the base end side lubricating oil passage 33b and the tip end side lubricating oil passage 33c, and the mounting hole 39 of the lubricating oil filter 38 has a stopper plug. It is sealed by 40.

Some spindle devices of machine tools and the like have a swing type in which the angle of the spindle can be adjusted arbitrarily. When the angle of the spindle is changed, the lubricating oil nozzle mounted on the housing is correspondingly changed. The equipment posture also changes. Therefore, by changing the angle of the main shaft, the above-mentioned base end side lubricating oil passage 33
The included angle θ between b and the horizontal direction or the included angle φ between the tip side lubricating oil passage 33c and the horizontal direction deviates from the initially set range, and setting these angles θ and φ alone will cause the outside of the vicinity of the discharge port 33a. It may not be possible to suppress the influence of airflow as originally set.

However, as described above, the lubricating oil nozzle 33
If the check valve 37 is provided in the middle of the lubricating oil path, the check valve 37 restricts the amount of lubricating oil sucked out, and at the same time air bubbles invading by sucking out the air inside the nozzle. It is possible to prevent the lubricating oil passage from flowing backward. Therefore, when the lubricating oil nozzle 33 of the present embodiment is used, even if the lubricating oil is sucked out of the lubricating oil nozzle 33 due to the air flow caused by the rotation of the shaft and the rolling bearing, it is impossible to discharge the lubricating oil. In the high-performance spindle device in which the spindle does not swing, the air bubbles mixed in the nozzle at the time of suction do not flow backward in the nozzle and deteriorate the discharge performance, and the spindle is a swing type. It is possible to improve the reliability of lubrication performance during high-speed operation regardless of the orientation of the spindle.

FIG. 9 shows a third embodiment of the spindle device according to the present invention. Spindle device 200 shown here
Is a shaft 43, a pair of rolling bearings 5 and 5 in which the inner surface of the inner ring 5a is fitted to the shaft 43, a housing 47 in which the outer surface of the outer ring 5b of the rolling bearing 5 is fitted, an inner ring 5a and an outer ring 5b.
And a lubricating oil supply mechanism 51 that supplies lubricating oil to each rolling bearing 5 that is relatively rotatable via the rolling elements 5c, and the central axis of the shaft 43 that serves as the main shaft extends in the vertical direction. It has been set.

The lubricating oil supply mechanism 51 includes the rolling bearings 5,
5. Lubricating oil nozzles 61 and 62 for injecting lubricating oil to No. 5, a minute lubricating device (not shown) for supplying a minute amount of lubricating oil to the lubricating oil nozzles 61 and 62, and lubricating oil output from the minute lubricating device for each lubricating oil nozzle. 61, 62 are provided with pipes 64, 65 leading to the rolling bearings 5, 5 with a discharge speed of 10 to 100 m.
/ Sec range, and the discharge amount is 0.
A small amount of lubricating oil in the range of 0005 to 0.01 ml is intermittently injected and supplied from the lubricating oil nozzles 61 and 62.

In the case of the present embodiment, the pair of rolling bearings 5 and 5 are arranged on the shaft 43 so as to face each other so as to be separated from each other by a predetermined distance in the axial direction and have contact angles opposite to each other.

The lubricating oil nozzle 62 for injecting lubricating oil to one of the pair of rolling bearings 5 and 5 serves as a lubricating oil passage for guiding the lubricating oil to the discharge port 62a at the tip, and is linear along the axial direction of the nozzle body. End-side lubrication oil passage 6 formed in a circular shape
2b, the tip of the base side lubricating oil passage 62b and the discharge port 6
2a, the tip side lubricating oil passage 62c is formed linearly along the discharging direction of the lubricating oil.
Further, the volume of the front end side lubricating oil passage 62c is set to be less than the discharge amount per shot by the lubricant oil nozzle 62, and the direction of the base end side lubricating oil passage 62b is set between the central axis and the horizontal line. The included angle θ is set to 10 °, which falls within the range of 10 to 170 °.

The lubricating oil nozzle 61 for injecting lubricating oil to the other of the pair of rolling bearings 5 serves as a lubricating oil passage for guiding the lubricating oil to the discharge port 61a at the tip, and is linear along the axial direction of the nozzle body. The drilled base end side lubricating oil passage 61b
And the tip of this base end side lubricating oil passage 61b and the discharge port 61a.
And a distal end side lubricating oil passage 61 having a length of 3 mm or more, which is bored linearly along the lubricating oil discharge direction so as to communicate with
c, and the volume from the discharge port 61a of the tip side lubricating oil passage 61c to 3 mm is set to be less than the discharge amount per one shot by the lubricant oil nozzle 61. Further, the direction of the tip side lubricating oil passage 61c is set. The included angle φ between the central axis and the horizontal line is set to 80 °, which falls within the range of 20 to 160 °.

In the example of the main spindle device of the vertical shaft as in the present embodiment, for the nozzle 61 in which the nozzle can be arranged under the bearing, the angle φ of the lubricating oil passage on the tip side should be within an appropriate range. Although it is easy, for the nozzle 62 in which the nozzle cannot be arranged under the bearing for the sake of space, it is impossible to set the angle φ of the tip side lubricating oil passage within an appropriate range.

Therefore, in the nozzle 62, the base end side lubricating oil passage is formed at an angle with respect to the axis of the nozzle to set the angle θ of the base end side lubricating oil passage within an appropriate range. By properly setting at least one of the angle θ and the angle φ for all of the bearings constituting the main shaft device, the influence of oil suction due to the airflow near the nozzle discharge port is reduced to maintain good lubrication performance. It is possible to construct a highly reliable spindle device.

FIG. 10 shows a fourth embodiment of the spindle device according to the present invention. In the main spindle device 300 of the present embodiment, the lubricating oil nozzle 85 that injects a small amount of lubricating oil to the rolling bearing 83 that rotatably supports the shaft 81, is the same as in the above-described respective embodiments. Discharge port 85
As the lubricating oil path leading to a, a base side lubricating oil path 85b linearly bored along the central axis of the nozzle body of the lubricating oil nozzle 85 and a distal side lubricating oil path 85c passing through the discharge port 85a are provided. However, instead of configuring the base end side lubricating oil passage 85b and the tip end side lubricating oil passage 85c to be continuous on a straight line, the equipment orientation of the lubricating oil nozzle 85 is set.

In order to reduce the influence of suction, the tip side lubricating oil passage 85c has a length of 3 mm or more,
3 mm from the discharge port 85a of the tip side lubricating oil passage 85c
Up to less than the discharge amount per shot by the lubricating oil nozzle 85, and further, the tip side lubricating oil passage 8
The orientation of 5c is set to 20 °, where the included angle φ between the central axis and the horizontal line falls within the range of 20 to 160 °.

With this structure, the lubricating oil nozzle 8
When manufacturing 5, the base end side lubricating oil passage 85b and the front end side lubricating oil passage 85c can be processed at a stretch, and the productivity of the lubricating oil nozzle 85 can be improved by reducing the number of processing steps. Therefore, the processing cost can be reduced.

The spindle device of the present invention is not limited to the above-mentioned embodiment, but can be appropriately modified and improved. For example, the micro-lubrication device used in the present invention is not limited to the configuration in which a very small amount of lubricating oil is discharged by the reciprocal movement of the giant magnetostrictive element described above. For example, a micro-lubrication device itself, an appropriate pump that continuously discharges lubricating oil at a predetermined pressure,
As a configuration including a switching valve that is connected to the discharge port of the pump and controls the discharge amount and discharge speed of the lubricating oil from the pump,
It is also possible to employ a known pump that uses an electric motor or the like as a drive source for the pump. Further, the specific structure of the housing is not limited to the structure of the above-described embodiment.

[0063]

As described above, according to the spindle device of the present invention as set forth in claim 1, the conventional oil mist of the direct injection type in which the lubricating oil is directly injected to the rolling bearing without using the compressed air. The lubricating oil particles injected to the bearing are larger than those of the oil-air system and the oil-air system, and the discharge speed is 10 to 10.
Large in the range of 100 m / sec. Therefore, the inertial mass of the lubricating oil particles injected into the bearing is large, and the lubricating oil particles injected from the lubricating oil nozzle easily penetrate the air curtain formed on the outer periphery of the shaft during high-speed operation of the shaft, Can reach a predetermined part of Therefore, during high-speed operation of the shaft, the lubricating oil supply to the bearing is not hindered by the air curtain formed on the outer periphery of the shaft, and stable lubrication oil supply during high-speed operation of the shaft ensures good lubrication of the bearing. Can be maintained in a state.

Further, unlike the case of the oil mist system or the oil air system, since compressed air is not used for injecting the lubricating oil and the compressed air does not collide with the rolling elements of the rolling bearing, no wind noise is generated. It is possible to prevent the generation of noise due to wind noise.

Furthermore, since the lubricating oil to be supplied is a very small amount or an extremely small amount with the discharge amount and discharge speed limited, excessive supply of the lubricating oil does not occur as compared with the case of the conventional jet system.
It is possible to avoid problems such as an increase in bearing temperature and an increase in driving torque loss due to excessive supply of lubricating oil.

Further, since the amount of lubricating oil to be injected and supplied is very small,
As the pump means provided in the lubricating oil supply mechanism, a small one that discharges a small amount of lubricating oil can be used as compared with the conventional jet method. By downsizing the pump means for lubricating oil and downsizing the compressed air source, it is possible to downsize the device and reduce the cost.

Further, in the main spindle device, normally, the air flow generated around the shafts and bearings by the rotation of the shafts and bearings acts on the discharge port of the lubricating oil nozzle to remove the lubricating oil remaining in the nozzle. Sucking occurs. Then, instead of the sucked lubricating oil, air enters the nozzle. The phenomenon of sucking out the lubricating oil in the nozzle due to the air flow around the nozzle becomes stronger as the rotational speed of the shaft is increased, and when a certain amount of air or more enters the nozzle, the compressibility of the air causes
There is a possibility of causing a serious obstacle that makes it impossible to discharge the lubricating oil.
In addition, even if the amount of invading air is a small amount, if the air becomes bubbles and flows backward in the nozzle to the pump side, and remains in a deep position in the nozzle or in pipes connected to the nozzle, etc., Due to the compressibility of the remaining bubbles, the discharge pressure may fluctuate or the discharge may become impossible.

However, in the above structure, the lubricating oil passage in the lubricating oil nozzle is provided with the tip side lubricating oil passage which receives the action of sucking the lubricating oil by the air flow near the discharge port and the base inside the nozzle which is hard to receive the sucking action. It is composed of the end side lubricating oil path,
The inner volume of the tip side lubricating oil passage is set to be less than the discharge amount of one shot. Therefore, even if all the lubricating oil in the tip-side lubricating oil passage is sucked out by the external air flow, the next one shot of lubricating oil discharge has a larger amount than the sucked lubricating oil and At the same time that the air intruding from the air can be discharged, the lubricating oil having the difference between the original discharge amount and the suction amount can be injected into the rolling bearing, and the serious obstacle of unlubrication does not occur. Moreover, when the equipment angle θ of the base end side lubricating oil passage is set to 10 to 170 ° with respect to the horizontal, the intersection of the tip end side lubricating oil passage and the tip end side lubricating oil passage is sucked into the inside of the nozzle. Since the air bubbles that enter air will not be able to pass through the bent portion, the air bubbles that have inhaled by suction will not flow backwards in the proximal lubrication oil path beyond the tip side lubrication oil path in the nozzle. It is possible to prevent the inconvenience that air bubbles are mixed and remain in a deep position in the nozzle or a pipe connected to the nozzle.

In summary, the spindle device of the present invention can maintain stable shaft rotation performance by ensuring good lubrication performance even when the rotation speed of the shaft is increased.
Wind noise can be eliminated to reduce noise. Furthermore, by preventing the accumulation of lubricating oil and the excessive supply of oil, it is possible to prevent an increase in agitation resistance on the rolling bearings and to reduce the drive energy of the shaft. Can be saved, and the device can be made compact by downsizing the drive source. Moreover, even if the lubricating oil in the lubricating oil nozzle is sucked out by the air flow caused by the rotation of the shaft or the bearing, it does not cause a serious obstacle such as inability to discharge the oil, and it is mixed in the nozzle at the time of sucking out. It is possible to improve the reliability of the lubrication performance during high-speed operation without causing air bubbles to flow backward in the nozzle to deteriorate the ejection performance.

Further, the spindle device of the present invention according to claim 2 is a direct injection type in which a very small amount or an extremely small amount of lubricating oil is directly injected to the bearing without using compressed air.
In common with the spindle device described in, in this regard,
It is possible to obtain the same action and effect as the spindle device according to the first aspect. Further, the influence of the suction by the external air flow generated near the discharge port of the lubricating oil nozzle due to the rotation of the shaft and the bearing can be mitigated / controlled by adjusting the included angle φ formed by the front end side lubricating oil passage being horizontal. Further, as described above, the included angle φ formed by the front end side lubricating oil path being horizontal is 20 to 16
By setting the range to 0 °, the influence of suction can be limited to a range of about 3 mm from the discharge port at the tip of the tip side lubricating oil path, and the volume in the path from the discharge port to 3 mm per shot By setting less than the discharge amount of
Limit the amount of lubricating oil sucked out from the lubricating oil nozzle by the external air flow to less than the amount of one shot discharged from the lubricating oil nozzle, and the air bubbles that have invaded by sucking out exceed the lubricating oil passage on the tip side in the nozzle. As a result, it is possible to prevent reverse flow in the base end side lubricating oil passage. Therefore, also in the case of the spindle device according to the second aspect, even if the lubricating oil is sucked out from the lubricating oil nozzle due to the airflow caused by the rotation of the shaft and the bearing, a serious obstacle such as incapability of discharging is caused. In addition, air bubbles mixed in the nozzle at the time of suctioning do not flow backward in the nozzle to reduce discharge performance, and reliability of lubrication performance at high speed operation can be improved.

The spindle device of the present invention according to claim 3 is a direct injection type in which a very small amount or an extremely small amount of lubricating oil is directly injected to the bearing without using compressed air.
In common with the spindle device described in, in this regard,
It is possible to obtain the same action and effect as the spindle device according to the first aspect. In addition, there is a swinging type spindle device in which the angle of the spindle can be arbitrarily adjusted in the above-mentioned spindle device subject to the direct injection type lubrication, and when the angle of the spindle is changed, the lubricating oil nozzle Also changes the equipment posture. for that reason,
By changing the angle of the main shaft, the included angle θ between the base end side lubricating oil path and the horizontal direction and the included angle φ between the tip side lubricant oil path and the horizontal direction deviate from the initially set range, and these angles θ , Φ may not be able to suppress the influence of the external air flow in the vicinity of the discharge port as originally set. However, as described above, if the check valve is provided in the middle of the lubricating oil path of the lubricating oil nozzle, the action of the check valve limits the amount of lubricating oil that is sucked out, and at the same time, it intrudes by suction. It is possible to prevent the generated air bubbles from flowing back through the lubricating oil passage in the nozzle. Therefore, also in the case of the spindle device according to the third aspect, even if the lubricating oil is sucked out from the lubricating oil nozzle due to the air flow caused by the rotation of the shaft and the bearing, a serious obstacle such as incapability of discharging occurs. In addition, air bubbles mixed in the nozzle do not flow backward in the nozzle at the time of suction and do not deteriorate the discharge performance, and even in a high-performance spindle device in which the spindle is a swing type, the orientation of the spindle Irrespective of the above, it is possible to improve the reliability of lubrication performance during high-speed operation.

Further, in the spindle device of the present invention as set forth in claim 4, even if any of the lubricating oil nozzles is selected due to the installation space or the like, any of the lubricating oil nozzles has a discharge port by an external air flow. It is possible to reduce the action of sucking the lubricating oil from the oil and maintain good lubricity.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a first embodiment of a spindle device according to the present invention.

2 is a vertical cross-sectional view of the lubricating oil nozzle shown in FIG.

3 is a view on arrow A in FIG. 2. FIG.

FIG. 4 is a schematic view of a nozzle tip in a lubricating oil nozzle.

5 is an explanatory diagram showing the correspondence between the setting range of the angle θ in the lubricating oil nozzle shown in FIG. 2 and the behavior of air bubbles that have entered the nozzle.

FIG. 6 is an explanatory diagram of an example of forming a leading end side lubricating oil passage in the lubricating oil nozzle shown in FIG.

FIG. 7 is a diagram showing a horizontal angle of the lubricating oil passage on the tip side, and
It is a graph which shows the relationship with the length of the bubble which penetrates into a tip side lubricating oil course.

FIG. 8 is a vertical cross-sectional view of a lubricating oil nozzle according to a second embodiment of a spindle device according to the present invention.

FIG. 9 is a vertical sectional view of a third embodiment of a spindle device according to the present invention.

FIG. 10 is a vertical cross-sectional view of a fourth embodiment of a spindle device according to the present invention.

[Explanation of symbols]

3 axes 5 Rolling bearing 5a inner ring 5b outer ring 5c rolling element 7 housing 11 Lubricating oil supply mechanism 13 Lubricating oil nozzle 13a outlet 13b Base end side lubricating oil path 13c Tip side lubricating oil path 23 nozzle tips 43 axes 61 Lubricating oil nozzle 61a discharge port 61b Base end side lubricating oil path 61c Tip side lubricating oil path 62 Lubricating oil nozzle 62a outlet 62b Base end side lubricating oil path 62c Tip side lubricating oil path 81 axes 83 bearings 85 Lubricating oil nozzle 85a outlet 85b Base end side lubricating oil path 85c Tip side lubricating oil path 100 spindle device 200 Spindle device 300 Spindle device

Claims (4)

[Claims] 1. A shaft, a bearing having an inner ring inner diameter surface fitted to the shaft, and a housing having an outer ring outer diameter surface fitted to the bearing.
In a spindle device including a lubricating oil supply mechanism that supplies lubricating oil to the bearing in which the inner ring and the outer ring are relatively rotatable via rolling elements, the lubricating oil supply mechanism lubricates the bearing. A lubricating oil nozzle for injecting oil and a micro-lubrication device for supplying a very small amount of lubricating oil to the lubricating oil nozzle are provided, and the bearing has a discharge speed in the range of 10 to 100 m / sec and a discharge amount of 1 A small amount of lubricating oil in the range of 0.0005 to 0.01 ml per shot is intermittently injected and supplied from the lubricating oil nozzle, and the lubricating oil nozzle serves as a lubricating oil path for guiding the lubricating oil to the discharge port at the tip. A base end side lubricating oil passage formed in a straight line along the axial direction of the nozzle body, and a lubricating oil discharge direction so that the tip end of the base end side lubricating oil passage and the discharge port communicate with each other. Was drilled in a straight line An end side lubricating oil passage is provided, and the volume of the leading end side lubricating oil passage is set to be less than the discharge amount per shot by the lubricating oil nozzle, and the direction of the base end side lubricating oil passage is set to the center thereof. A spindle device characterized in that an included angle θ between an axis and a horizontal line is set to fall within a range of 10 to 170 °. 2. A shaft, a bearing having an inner ring inner diameter surface fitted to the shaft, and a housing having an outer ring outer diameter surface fitted to the bearing.
In a spindle device including a lubricating oil supply mechanism that supplies lubricating oil to the bearing in which the inner ring and the outer ring are relatively rotatable via rolling elements, the lubricating oil supply mechanism lubricates the bearing. A lubricating oil nozzle for injecting oil and a micro-lubrication device for supplying a very small amount of lubricating oil to the lubricating oil nozzle are provided, and the bearing has a discharge speed in the range of 10 to 100 m / sec and a discharge amount of 1 A small amount of lubricating oil in the range of 0.0005 to 0.01 ml per shot is intermittently injected and supplied from the lubricating oil nozzle, and the lubricating oil nozzle serves as a lubricating oil path for guiding the lubricating oil to the discharge port at the tip. The lubricating oil nozzle is provided with a tip side lubricating oil path having a length of 3 mm or more, which is linearly bored along the lubricating oil discharge direction, and has a volume of 3 mm from the discharge port of the tip side lubricating oil path. By 1 It is set to be less than the discharge amount per knot, and the orientation of the tip side lubricating oil passage is set so that the included angle φ between the central axis and the horizontal line falls within the range of 20 to 160 °. And spindle device. 3. A shaft, a bearing having an inner ring inner diameter surface fitted to the shaft, and a housing having an outer ring outer diameter surface fitted to the bearing.
In a spindle device including a lubricating oil supply mechanism that supplies lubricating oil to the bearing in which the inner ring and the outer ring are relatively rotatable via rolling elements, the lubricating oil supply mechanism lubricates the bearing. A lubricating oil nozzle for injecting oil and a micro-lubrication device for supplying a very small amount of lubricating oil to the lubricating oil nozzle are provided, and the bearing has a discharge speed in the range of 10 to 100 m / sec and a discharge amount of 1 A small amount of lubricating oil in the range of 0.0005 to 0.01 ml per shot is intermittently injected and supplied from the lubricating oil nozzle, and the lubricating oil nozzle is in the middle of the lubricating oil path for guiding the lubricating oil to the discharge port at the tip. At a position where the volume from the discharge port is less than the discharge amount per shot by the lubricating oil nozzle,
A spindle device having a check valve for preventing backflow. 4. A shaft, a plurality of bearings whose inner ring inner diameter surface is fitted to the shaft, a housing in which the outer ring outer diameter surface of the bearing is fitted, and the inner ring and the outer ring are opposed to each other via rolling elements. In a main spindle device including a lubricating oil supply mechanism that supplies lubricating oil to the plurality of bearings that have become rotatable, the lubricating oil supply mechanism includes a plurality of bearings that respectively inject the lubricating oil. A spindle device comprising a lubricating oil nozzle, wherein the plurality of lubricating oil nozzles are the nozzles according to any one of claims 1 to 3.