JPH08210574A - Rotary sealing joint of spindle, etc. - Google Patents

Abstract

PURPOSE: To provide a rotary sealing joint of a spindle or the like, capable of coping with a high rate of speed without oil leakage by making a fixed side member contact and impart, at constant pressure, to a rotary side member of a rotary sealing member by means of a constant-pressure mechanism utilized with a spring force. CONSTITUTION: In this rotary sealing joint which is dominant over a supply of cooling lubricant C to a center hole 7B of a drawing bar 7 and a discharge of this cooling lubricant C from a spindle tail end hole 1E or supply to this hole 1E, it is composed of two joints K1 and K2 which are featured that two rotary members 20 and 60 fitted in an end of each rotator of the drawing bar 7 and a spindle 1 or the like and two pressuring members 40 and 80 contacting after each of pressuring forces P1 and P2 is imparted to each end of both these rotary members by means of spring materials 30 and 70, etc., are installed in a stationary body or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary seal joint for a spindle of a machine tool or the like, which not only suppresses leakage of pressure fluid to a minimum but also enables control of contact surface pressure of the rotary seal joint. Involve

[0002]

2. Description of the Related Art Conventionally, in rotary seal joints such as spindles of machine tools, as disclosed in Japanese Patent Laid-Open No. 60281/1992,
A fixed circular pipe and a rotating circular pipe are fitted in a non-contact manner with a radial gap therebetween in the longitudinal direction thereof, and an annular groove is provided on the fitted insertion surface, and a suction device is provided in the suction passage communicating with this groove. A rotary seal member is provided. According to this rotary seal member, even if the forward path and the return path of the cooling liquid are combined, it is sufficient to provide the annular groove and the suction path in only one direction, and there is an advantage that the sealing structure is simple. In addition, JP-A-6-2413
In No. 66, a diaphragm, which urges a pair of seal members provided on the opposing surfaces of the rotary shaft and the moving shaft of the rotary joint in a non-contact state, is stretched between the housing and the moving shaft. And, when the gas is circulated to the fluid channel,
When introducing gas into the port and leaving the pair of seal members in a non-contact state to allow the fluid to flow, introduce liquid into the port and press the diaphragm with that pressure to bring the pair of seal members into contact. To do.

[0003]

However, according to the rotary seal member disclosed in Japanese Patent Laid-Open No. 4-60281, the suction force is reduced due to a trouble of the suction device, and the insertion surface where the fixed circular pipe and the rotary circular pipe are fitted to each other. Oil leaks from the annular groove.
Further, the fitting gap between the fixed circular pipe and the rotary circular pipe varies due to unbalance and rotary vibration of the rotary circular pipe, so that the suction and recovery efficiency of lubrication decreases. Furthermore, JP-A-6-241366
In the rotary joint of No. 3, when a gas is introduced into the port, the pair of seal members are kept in a non-contact state, and when the fluid is circulated, the pressure is applied to the diaphragm to bring the pair of seal members into a contact state. Therefore, in addition to the complicated operation mechanism of the seal member, the operation is unstable due to pressure fluctuation and the like, which lowers the fluid suction efficiency and causes many failures. .

After all, oil leakage from the pair of seal members or the fitting gap between the fixed circular pipe and the rotary circular pipe cannot be avoided, and an oil leakage suction and recovery device is indispensable. Has become. Therefore, there is a problem that the operating mechanism of the seal member becomes complicated and the peripheral equipment becomes large-scale.

In view of the problems of the above-described conventional rotary seal member, the present invention provides a fixed pressure member in contact with the rotary side member of the rotary seal member at a constant pressure by a constant pressure mechanism utilizing a spring force, thereby causing oil leakage. It is an object of the present invention to provide a rotary seal joint for a main shaft or the like that is capable of coping with high speed rotation without any problems.

[0006]

In order to achieve the above-mentioned object, the present invention provides, in claim 1, the supply of the cooling lubricating liquid to the central hole of the drawing bar, the discharge of the cooling lubricating liquid from the tail end hole of the main spindle, or the main spindle. In the rotary seal joint that controls the supply to the tail end hole, the rotating member fitted to the end of the rotating body such as the drawing bar and the main shaft, and the end face of this rotating member are pressed by the spring material etc. A rotary seal joint for a main shaft or the like, characterized in that a pressurizing member that comes into contact with the stationary body is installed.

According to a second aspect of the present invention, in the first aspect, the rotating member is made of a ceramic material having excellent wear resistance, chemical resistance, heat resistance, and low friction coefficient. Etc. is a rotary seal joint.

According to a third aspect of the present invention, in the first aspect of the present invention, the pressure member is made of a carbon material excellent in wear resistance, heat resistance, low friction coefficient and the like. It is a rotary seal joint.

[0009]

According to the first aspect of the present invention, the rotating member and the contact wheel piece of the pressing member for applying a predetermined pressing force to the rotating member,
Since the contact pressure between the two is controlled to be constant, it functions as a rotary seal joint without leaking the cooling lubricant regardless of the factors such as the rotation and stop of the rotating body such as the drawing bar and the main shaft, and external fluctuations. In particular, at the time of high-speed rotation of the main shaft or the like, a centripetal action is exerted on the rotating member that rotates integrally with the main shaft, and the function of preventing liquid leakage is exerted for a long period of time.

According to the second and third aspects of the present invention, in addition to the action according to the first aspect, liquid leakage, heat generation, abnormal wear, etc. are not observed in the rotary seal joint even when the rotating body rotates at high speed, and more than 10 years have passed. The effect of guaranteeing a long life is exhibited.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments shown in the drawings will be described below. FIG. 1 is an overall sectional view of a spindle device including a rotary seal joint such as a spindle according to the present invention, and FIG. 2 is a partially enlarged sectional view of a spindle device including a rotary seal joint such as a spindle according to the present invention. .

In FIG. 1, the spindle 1 of the spindle device 100.
Is supported at its tip end by two bearings 2, 3,
The rear end side is supported by one bearing 4. The main shaft 1 has a built-in motor BM in the middle portion 1A thereof.
No. 5 rotor is fitted, and a multilayer disc spring 6 and a drawing bar 7 are installed in the inner peripheral hole 1B opened at the axial center position, and the tool T inserted into the tapered hole 1C at the tip of the main shaft is pulled in strongly. Fit in. And the above drawing bar 7
At the rear end 7A, the piston 11 of the unclamp device 10 is
Is fitted in the cylinder 12, and the drawing bar 7 is strongly pushed out to perform the unclamping operation when the drawing clamp is retracted and the drawing bar 7 is advanced to the drawing bar 7 side. Then, normally, as shown in FIGS. 1 and 2, the piston 11 is in a retracted unclamped state.

The piston 11 of the unclamp device 10
The tail end hole portion 11A is supplied with a cooling lubricating liquid C for cooling the shaft core of the main shaft 1 and for underrace lubrication of the three bearings 2, 3 and 4. Piston 11 tail end hole 11A
The cooling lubricating liquid C supplied to the inside of the drawing bar 7 is sent from the through hole 11B of the piston 11 into the central hole 7B of the drawing bar 7 through the contact type first rotary seal joint K1 and is opened at the tip of the drawing bar 7. It flows from the hole 7C into the inner peripheral hole 1B of the main shaft 1 facing the outer periphery of the drawing bar 7. Most of the cooling lubricating liquid C flowing into the inner peripheral hole 1B of the main shaft 1 is
While cooling the entire length of the main shaft 1, the main shaft abdomen 1
The heat from the rotor 5 which is generated in a large amount in A is cooled, and passes through the inner peripheral gap X of the contact type second rotary seal joint K2 interposed between the main shaft tail end hole portion 1E and the machine frame B to form the machine frame B. Through hole B1
Is discharged to the outside as a shaft core cooled liquid. These cooling lubricating liquids C are sent into the center hole 7B of the drawing bar 7 from the through hole 11B of the piston 11 again through the contact type first rotary seal joint K1 after cooling by a cooling device (not shown).

On the other hand, a part of the cooling lubricating liquid C that has flowed into the inner peripheral hole 1B of the main shaft 1 passes through the inner peripheral hole 1B in the radial direction in order to perform underrace lubrication of the three bearings 2, 3 and 4. Inner ring 2 of each bearing 2, 3 and 4 has holes 1F, 1G and 1H
Contact A, 3A, 4A. As a result, a part of the cooling lubricating liquid C flows from the inner peripheral hole 1D to the through holes 1F, 1G, 1H.
And is supplied to the inner rings 2A, 3A, 4A of the bearings 2, 3, 4 to carry out underrace lubrication. The cooling lubricant C after lubricating the tip end side bearings 2 and 3 of the main spindle 1 is collected from the drain passage 12A on the main spindle fixed machine frame 12 side to the discharge passage 12B, and after the rear end side bearing 4 of the main spindle 1 is lubricated. Cooling lubricant C
From the drain passage 12C on the main shaft fixing machine frame B side to the discharge passage 1
Collected in 2D, each released as a lubricated liquid.

The winding coil 1 of the built-in motor BM
The outer cylinder cooling liquid C1 is sent from the passage 12E on the main spindle fixing machine frame 12 side to the stator side cooling jacket 13A provided with 3, and the cooled outer cylinder cooling liquid C1 is discharged to the outside from the passage 12F. . The outer cylinder cooling liquid C1 is fed again from the passage 12E after being cooled by a cooling device (not shown).

FIG. 2 shows a schematic structure of the first rotary seal joint K1 and the second rotary seal joint K2. First, the first rotary seal joint K1 for feeding the cooling lubricant C from the center through hole 11B of the piston 11 into the rear end center hole 7A of the drawing bar 7 is the rotary member fitted to the rear end 7C of the drawing bar 7. 20 and a pressurizing member 40, which applies a pressing force P1 to the rear end surface of the piston 11 by the spring member 30, are provided in the expanded diameter portion 11C of the central through hole 11B of the piston 11. or,
The contact type second rotary seal joint K2 interposed between the spindle tail end hole 1E and the machine frame B has a rotary member 60 engaged with the ring body 50 of the spindle tail end hole 1E and a rear end surface of the rotary member 60. A pressurizing member 80, which applies a pressing force P2 with a spring member 70 and comes into contact with the spring member 70, is provided in a support ring 90 fixed to the machine frame B.

Next, the detailed structure of the first rotary seal joint K1 will be described with reference to FIG. Rear end 7 of drawing bar 7
An annular rotary member 20 is fitted in a ring-shaped holder 21 having a U-shaped cross section fitted in C, and is integrally supported by a pin 22 so as to be movable only in the axial direction. On the other hand, the annular pressure member 40
Is an annular holder 4 having an inverted Y-shaped cross section, which is integrally provided on the expanded diameter portion 11C of the piston 11 with a pin 43 so as to be movable only in the axial direction.
A plurality of spring members 30 are movably fitted on the circumference of the concave portion 42 in FIG. The spring member 30 evenly applies the pressing force P1 to the pressing member 40 on the circumference thereof, and the rotating member 20 of the rotating member 20 contacting the pressing force P1 via the contact wheel piece 40A of the pressing member 40. The end face is provided with the function of the centripetal mechanism.

The rotating member 20 is made of a lightweight ceramic material having excellent wear resistance, chemical resistance, heat resistance, and low friction coefficient. Further, as the material of the pressing member 40, a carbon material excellent in wear resistance, heat resistance, low friction coefficient, etc. is adopted. By adopting these materials, the rotary member 20 and the contact wheel piece 40A of the pressurizing member 40 that applies a predetermined pressing force P1 thereto can fulfill the function of the rotary seal joint K1 without leaking the cooling lubricating liquid C. It is possible and guarantees a long life of 10 years or more even at high speed rotation.

Next, the detailed construction of the second rotary seal joint K2 will be described with reference to FIG. A ring body 50 having a holder portion 51 having a U-shaped cross section is fastened to the spindle tail end hole portion 1E with a bolt 52. An annular rotary member 60 is fitted into the holder portion 51 and integrally provided with a pin 53 so as to be movable only in the axial direction. On the other hand, the annular pressure member 80
Is integrally provided on an inner peripheral surface of a spline cylinder 92 fitted to an inner peripheral wall of a holder portion 91 having a U-shaped cross section of the support ring 90 fixed to the machine frame B so as to be movable only in the axial direction. The plurality of spring members 30 provided on the circumference of the concave portion 93 of the support ring 90 uniformly apply the pressing force P2 to the pressing member 80 on the circumference, and the pressing force P2 is applied to the pressing member 80. Contact wheel 80A
The end face of the rotating member 60 that comes into contact with the center of the rotary member 60 is provided with the function of the centripetal mechanism. A gap X is provided between the inner peripheral surface of the ring member 50 or the support ring member 90 and the outer peripheral surface of the drawing bar 7, and the cooling lubricating liquid C that has been spindle-cooled from the gap X passes through the through hole B1 of the machine frame B. The second rotary seal joint K2 serves to prevent the cooling lubricant C from leaking.

As the material of the rotating member 60, a ceramic material which is lightweight and excellent in wear resistance, chemical resistance, heat resistance, low friction coefficient and the like is adopted. As the material of the pressing member 80, a carbon material having excellent wear resistance, heat resistance, low friction coefficient, etc. is adopted. By adopting these materials, the rotating member 60 and the contact wheel piece 80A of the pressurizing member 80 for applying a predetermined pressing force P2 thereto are cooled by the cooling lubricant C.
The function of the rotary seal joint K2 can be fulfilled without leaking, and a long life of 10 years or more is guaranteed even at high speed rotation.

The rotary seal joints K1 and K2 of the present invention are constructed as described above, and operate as follows. The tail end hole portion 11A of the piston 11 of the unclamp device 10 is supplied with a cooling lubricating liquid C for cooling the shaft core of the main shaft 1 and underrace lubrication of the three bearings 2, 3 and 4.
The cooling lubricating liquid C supplied to the tail end hole portion 11A is passed through the first rotary seal joint K1 to the through hole 11B of the piston 11.
Sent into the center hole 7B of the drawing bar 7,
From the through hole 7C opened at the tip of the drawing bar 7, it flows into the inner peripheral hole 1B of the main shaft 1 facing the outer periphery of the drawing bar 7. The first rotary seal joint K1 always exhibits a stable sealing action irrespective of the clamp and unclamp operation states of the unclamp device 10 and the rotation and stop of the main shaft 1.

That is, the contact pressure between the rotary member 20 and the contact wheel 40A of the pressing member 40 that applies a predetermined pressure P1 to the rotary member 20 is controlled to be constant, so that the main shaft 1 Rotating seal joint K without leaking cooling lubricant C regardless of factors such as rotation and stop and external fluctuations
Fulfills the function of 1. Further, even when the main shaft 1 rotates at a high speed, the centering function of the rotating member 20 that rotates integrally with the main shaft 1 allows the contact surfaces to evenly contact each other, and the function of preventing liquid leakage has the effect of exhibiting a long life of 10 years or more.

Next, most of the cooling lubricating liquid C that has flowed into the inner peripheral hole 1B of the main shaft 1 is cooled over the entire length of the main shaft 1, and at the same time, the heat from the rotor 5 which is generated in large quantities in the main shaft abdomen 1A is cooled. Then, through the inner peripheral clearance X of the contact-type second rotary seal joint K2 interposed between the spindle tail end hole portion 1E and the machine frame B, from the through hole B1 of the machine frame B to the outside as a shaft core cooled liquid. discharge. The second rotary seal joint K2 always exhibits a stable sealing action regardless of the rotation and stop of the main shaft 1.

That is, the contact pressure between the rotary member 60 and the contact wheel piece 80A of the pressing member 80 for applying a predetermined pressure P2 to the rotary member 60 is controlled to be constant, so that the main shaft 1 Rotating seal joint K without leaking cooling lubricant C regardless of factors such as rotation and stop and external fluctuations
Performs the function of 2. Further, even when the main shaft 1 rotates at a high speed, the centering function of the rotating member 60 that rotates integrally with the main shaft 1 allows the contact surfaces to evenly contact each other, and the liquid leakage preventing function has the effect of exhibiting a long service life of 10 years or more.

The cooling lubricating liquid C is contacted again with a first rotary seal joint K1 after cooling by a cooling device (not shown).
Through the through hole 11B of the piston 11 into the central hole 7B of the drawing bar 7. On the other hand, a part of the cooling lubricating liquid C that has flowed into the inner peripheral hole 1B of the main shaft 1 is a through hole 1F, 1G, 1H which is the underrace lubrication of the three bearings 2, 3, 4 which is opened radially from the inner peripheral hole 1B. From each bearing 2,
It flows into the inner rings 2A, 3A, 4A of 3, 4 and under-race lubricates. The cooling lubricating liquid C after lubricating the tip end side bearings 2 and 3 of the main shaft 1 is the drain passage 12 on the main shaft fixing machine frame 12 side.
The cooling lubricating liquid C collected from A to the discharge passage 12B and after lubricating the rear end side bearing 4 of the main shaft 1 is collected from the drain passage 12C on the main shaft fixed machine frame B side to the discharge passage 12D and is lubricated respectively. Discharge as liquid.

The present invention is not limited to the above-mentioned embodiments, and it is possible to change the design in details within the scope of the invention. For example, the rotary seal joints K1 and K2 are not limited to the above configuration, and the detailed partial configuration can be freely designed and changed.

[0027]

According to the first aspect of the present invention, by the rotating member and the contact wheel piece of the pressing member for applying a predetermined pressing force to the rotating member,
The contact pressure between the two is controlled to be constant by a simple construction means, so that the rotary seal does not leak the cooling lubricant regardless of the factors such as the rotation and stop of the rotating body such as the drawing bar and the main shaft, and external fluctuations. Performs the function of a joint. Further, even when the main shaft or the like rotates at a high speed, the centripetal function works on the rotating member that rotates integrally with the main shaft, so that the function of preventing liquid leakage is exerted for a long period of time.

According to claims 2 and 3 of the present invention, claim 1
In addition to the effect of the above, there is no effect of liquid leakage, heat generation, abnormal wear, etc. on the rotary seal joint even when the rotary body rotates at high speed, and there is an effect of guaranteeing a long life of 10 years or more.

[Brief description of drawings]

FIG. 1 is an overall cross-sectional view of a spindle device including a rotary seal joint for a spindle or the like according to the present invention.

FIG. 2 is an enlarged sectional view of a rotary seal joint for a main shaft and the like according to the present invention.

FIG. 3 is an enlarged cross-sectional view showing a detailed configuration of the first rotary seal joint of the present invention.

FIG. 4 is an enlarged cross-sectional view showing a detailed configuration of the second-time sealed rolling joint of the present invention.

[Explanation of symbols]

1 Spindle 1E Spindle tail end hole 2,3,4 Bearing 2A, 3A, 4A Inner ring 7 Drawing bar 7C Through hole 10 Unclamping device 11 Piston 20,60 Rotating member 21 Ring holder 30,70 Spring member 40,80 Additional Pressure member 40A, 80A Contact wheel piece 41 Ring body holder 50 Ring body 90 Support ring body B Machine frame C Cooling lubricant C1 Outer cylinder coolant K1 First rotary seal joint K2 Second seal rolling joint

Claims (3)

[Claims] 1. A rotary seal joint that controls the supply of cooling lubricant to the center hole of the drawing bar, the discharge of cooling lubricant from the spindle tail end hole, or the supply to the spindle tail end hole. The rotating body fitted to the end of the rotating body, and the pressurizing member which is brought into contact with the end surface of the rotating member by a pressure applied by a spring material or the like are mounted on the fixed body or the like. Rotating seal joints for spindles, etc. 2. The rotary seal joint according to claim 1, wherein the rotary member is made of a ceramic material excellent in wear resistance, chemical resistance, heat resistance, low friction coefficient and the like. . 3. The rotary seal joint according to claim 1, wherein the pressure member is made of a carbon material having excellent wear resistance, heat resistance, and low friction coefficient.