JPH0724687A - Machine tool spindle device - Google Patents

Abstract

PURPOSE:To provide a mechanism capable of integrally performing lubricating a rotary bearing by lubricating liquid supplied from a single lubricating liquid supply source to the main spindle device of a machine tool and cooling the bearing, a main spindle, and a housing. CONSTITUTION:Lubricating liquid, introduced in a lubricating liquid path 46a provided on the center part of the main spindle device 10 of a machine tool from a lubricating liquid supply source 64, is supplied to a rotary bearing 18a, etc., provided on front and rear regions of a main spindle 14 to lubricate an under lathe and also axis-cooling the main spindle inside. An integrated lubricating and cooling mechanism is formed wherein after that the lubricating liquid is sent to a liquid flow passage 12b, etc., piped in a housing 12 in the surroundings of the rotary bearing 18a, etc., transfer heat to the housing 12 is effectively taken out, and then the lubricating liquid is recovered to be returned to the lubricating liquid supply source 64.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle device of a machine tool, and more particularly, it is rotatably supported in a housing through a rotary bearing and has a machining tool or other work tool or work at its tip. The main shaft, which has a mounting end that is detachably held, is supplied to the interior of the main shaft, the rotary bearing,
The present invention relates to a spindle device of a machine tool provided with a cooling / lubrication mechanism that lubricates a rotary bearing while sequentially providing cooling to a housing, cools and collects the lubricated liquid after lubrication, and returns it to a lubricating liquid supply source.

[0002]

2. Description of the Related Art A spindle device of a machine tool, in particular, has a tool mounting end on which a machining tool is mounted at a tip thereof, and a cooling liquid is caused to flow inside a spindle which rotates at a high speed to cool the spindle. The spindle device according to the present invention is disclosed, for example, in Japanese Patent Laid-Open No.
It is disclosed in Japanese Patent Publication No. 4-87130.

Similarly, in a main spindle device (spindle device) of a machine tool, a main spindle is supported by a plurality of rotary bearings spaced apart from each other inside a housing so as to be rotatable at a high speed, and these rotary bearings have a central portion of the main spindle. The radial oil formed in the lubricating oil supply spacers provided in the peripheral region of the drive rod (so-called drawbar) of the tool gripping means provided in Through an oil passage formed in the inner ring of each rotary bearing through a passage and an annular oil passage, and by supplying centrifugal force to the inside of the bearing to perform underrace lubrication, and to obtain a cooling effect with a lubricating liquid. This is disclosed in Japanese Utility Model Laid-Open No. 4-57355.

However, the former Japanese Patent Laid-Open No. 64-8713.
The cooling mechanism disclosed in Japanese Patent Publication No. 0 is a mechanism only for cooling purpose in which the internally generated heat of the main shaft, the rotary bearing, and the like is absorbed and cooled by using a cooling liquid, and thus a technology of no interest in the lubrication mechanism for the rotary bearing. It only discloses the contents. On the other hand, the latter main spindle device disclosed in Japanese Utility Model Laid-Open No. 4-57355 aims at the effect of cooling the internal region of the main spindle along the lubrication flow passage inside the main spindle in the process of underrace lubrication of the rotary bearing, in terms of lubrication. A mechanism for performing the dual action of cooling and cooling is disclosed.

[0005]

However, in the case of the spindle device disclosed in the above-mentioned Japanese Utility Model Publication, the lubricating liquid is circulated in the longitudinal direction along the inner peripheral surface of the spindle, and the spindle is directly fed from the inside. The technical idea of mechanical cooling is not understood. In addition, in the publication of the above-mentioned U.S. Pat. No. 5,961,861, since the lubricating liquid after lubricating the rotary bearing is configured to be collected and returned from a drainage outlet of the lubricating liquid formed in a part of the housing, it is generated during rotation of the rotary bearing. It does not have a mechanism to effectively cool the entire housing when heat is transferred to the housing. For this reason, there is a drawback in that the housing is heated and expanded, which affects the rotation accuracy and the like of the rotary bearing held in the housing.

Therefore, the object of the present invention is to provide all the structural elements of the main spindle device such as the main spindle, rotary bearing, housing, etc.
By simultaneously performing an appropriate cooling action by using the lubricating liquid that lubricates the rotary bearing, and further by depriving the main shaft side of the main shaft device and recirculating the cooled lubricating liquid to the housing side to absorb the heat and cool the same. The present invention provides a spindle device for a machine tool, in which the cooling effect on the latter side is alleviated and the seizure prevention effect of internal structural elements, particularly a rotary bearing, is improved. Another object of the present invention is to provide a spindle device of a machine tool capable of cooling and lubricating a spindle, a rotary bearing, a housing and the like even when a spindle through coolant device is built therein.

[0007]

In view of the above object, the present invention relates to a rotary bearing in which a lubricating liquid introduced into the central portion of a spindle of a machine tool is provided in the front region and the rear region of the spindle, respectively. It is sent to the inner region, and the respective rotary bearings are lubricated with the lubricating liquid, and the lubricating liquid is circulated in the axial direction along the inner peripheral surface of the main shaft to cool the main shaft from the inside. In addition, the circulating lubricating fluid is circulated to the liquid passage that is piped around the rotary bearing inside the housing around the main shaft to effectively take away the heat transferred from the rotary bearing to the housing to the outer peripheral area of the housing. This is to construct a comprehensive lubricating and cooling mechanism that gives a cooling effect and then recovers and returns the lubricating liquid.

That is, according to the present invention, in a spindle device of a machine tool in which a spindle is rotatably supported by a housing by a rotary bearing, the central portion of the spindle is communicated from the rear of the spindle toward the front of the spindle to supply a lubricating liquid. A lubricating liquid supply passage connected to the discharge side of the source, a bearing lubricating flow passage branched from the lubricating liquid supply passage in the radial direction and opening toward the rotary bearing, and a branch from the lubricating liquid supply passage Then, a shaft cooling passage for circulating a lubricating liquid along the inner peripheral surface of the main shaft to cool the inner surface of the main spindle, and a suction side of the lubricating liquid supply source from the bearing lubricating flow passage and the shaft core cooling flow passage. And a lubricant recovery path connected to the main shaft of the machine tool configured to both lubricate the rotary bearing and cool the main shaft of the main shaft.

Further, according to the present invention, in a spindle device of a machine tool in which a spindle is rotatably supported by a housing by a rotary bearing, the central portion of the spindle is communicated from the rear of the spindle to the front of the spindle to supply a lubricating liquid. A lubricating liquid supply passage connected to the discharge side of the source, a bearing lubricating flow passage branched from the lubricating liquid supply passage in the radial direction and opening toward the rotary bearing, and a branch from the lubricating liquid supply passage And a shaft cooling passage for circulating a lubricating liquid along the inner peripheral surface of the main shaft to cool the inner surface of the main shaft, and at least one of the lubricating liquid lubricated with the rotary bearing and the lubricating liquid cooled with the shaft. Lubrication of the rotary bearing, comprising: a housing cooling flow path for circulating the lubricating liquid in the housing; and a lubricating liquid recovery path connected from the housing cooling flow path to a suction side of the lubricating liquid supply source. Axis of the main shaft There is provided a retirement and machine tool spindle apparatus configured to perform both the cooling of the housing.

In the spindle device of a machine tool having the above-mentioned structure, appropriate sealing means for preventing the leakage of the lubricating liquid to the outside is provided in the vicinity of the rotary bearings arranged at the front and rear positions of the spindle. The sealing means may be constituted by a well-known oil sealing means, or it is also possible to supply pressurized air to seal in an air curtain system.

[0011]

According to the above construction, the lubricating liquid is supplied to the rotary bearing while the lubricating liquid is supplied from the lubricating liquid supply source through the lubricating liquid supply passage, the bearing lubricating passage and the shaft cooling passage. In addition to lubrication, heat and cool the spindle. Further, a lubricating liquid is circulated in the housing cooling passage to remove heat and cool the housing. The lubricating liquid that has performed the cooling action and the lubricating action, respectively, returns via the common lubricating liquid recovery path and returns to the lubricating liquid supply source and is recovered. Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

[0012]

1 is a sectional view showing a first embodiment of a spindle device for machine tools according to the present invention, and FIG. 2 is a sectional view showing a second embodiment of a spindle device for machine tools according to the present invention. is there. In FIG. 1, a spindle device 10 according to an embodiment of the present invention is
A housing 12 is provided, and the housing 12 is formed as a generally cylindrical hollow body, and rotatably accommodates the main shaft 14 along a central axis extending from the front to the rear. The main shaft 14 has a tapered hole-shaped mounting hole 16 in which a tool holder T and the like are mounted on the front end side, and a pair of rotary bearings provided at a front position of the housing 12 and spaced from each other by a spacer. 18a, 18b and a rotary bearing 18 provided at the rear position
It is rotatably supported by c and. A bearing retainer 20 is provided in front of the housing 12, and both rotary bearings 18a and 18b are fixed at fixed positions with a nut 22 provided on the rear side of the rotary bearing 18b. The rear rotary bearing 18c has one end in contact with a shoulder portion formed on the rear portion of the main shaft 14, and is pressed by a nut 22 from the other end side to be fixedly arranged at a fixed position.

In this embodiment, an attachment / detachment mechanism such as a tool holder T having a draw bar 24 is provided inside the center hole of the main shaft 14, and a pull stud provided at the rear end of the taper shank S of the tool holder T or the like. It has a mechanism for detachably mounting the taper shank S in the mounting hole 16 in cooperation with P. That is, when the draw bar 24 is pushed in from the rear end side of the main shaft 14 by the operation means arranged for detaching drive of the taper shank S described later, the grip of the pull stud P at the rear end of the taper shank is released and the mounting hole 16 is provided. When the draw bar 24 is pulled back by the return spring 28 such as a disc spring or a leaf spring arranged in the spring chamber 26 when the pushing means of the actuating means is released, the same tool is pulled through the pull stud P of the taper shank S. The holder or the like is drawn inwardly of the mounting hole 16 to be in the mounted state.

The above-mentioned operating means is, for example, the spindle device 10.
It is formed by the fluid cylinder device 30 arranged on the rear end side, and the cylinder device 30 is internally provided with a piston 32 that responds to the supply and discharge of the pressure fluid by the hydraulic pressure source 90. When the piston 32 moves forward, Drawbar 24
Is pressed forward, and at the same time, the movable sleeve member 34, which is screwed into the drawbar 24 and is integrated, advances to press the spring 28 at its front end side to accumulate a spring reaction force. When the piston 32 moves backward, the spring reaction force accumulated in the return spring 28 causes the drawbar 24 to move backward toward the rear end of the main shaft.

A guide sleeve 40 is provided on the outer periphery of the draw bar 24 at the front portion of the main shaft 14, and the tip of the guide sleeve 40 has a tool gripping ball 24a for collet operation housed at the end of the draw bar 24. Is formed, and the tool gripping ball 24a has a taper shank S.
The tool gripping ball 24a is received and retracted during disengagement in the process of engaging and disengaging the pull stud P and gripping the tool holder T and the like.

The guide sleeve 40 has a cylindrical shape,
The guide sleeve 40 is fixedly installed in a state in which it is in contact with and supported by a shoulder portion formed in the front end region of the main shaft 14 as a flow passage forming ring forming a part of a lubricating liquid flow passage described later. The end face of the is formed a seat for the return spring 28. On the rear end side of the main shaft 14, the above-mentioned movable sleeve member 34 similarly serves as the main shaft 1 as a cylindrical flow path forming ring.
The movable sleeve 34, which is movably fitted and disposed on the rear end side of No. 4, forms the passage for the return spring 28, as described above, and the rear end side of the movable sleeve 34 forms the flow passage forming ring. It slightly projects from the rear end of the main shaft 14 in the axial direction.

Further, the spindle device 10 according to this embodiment is formed as a self-supporting drive type spindle device having a drive motor built therein. Therefore, the rotor M1 is fixedly attached to the central region of the main shaft 14, and the stator M2 is fixedly attached to the housing 12 with a predetermined gap in the radial direction between the rotor M1 and the rotor M1. Due to the electromagnetic interaction, the main shaft 14 is rotationally operated at various rotational speeds and braked.

According to the present invention, the lubricating liquid introducing pipe 46 which is inserted through the central portion of the main shaft 14 in the radial direction, that is, the central hole of the draw bar 24 in this embodiment, is fitted.
The lubricating liquid introducing pipe 46 has a lubricating liquid flow path 46a that forms a lubricating liquid supply flow path inside, and the rear end thereof penetrates the piston 32 of the fluid cylinder device 30 and projects to the outside of the spindle device 10, It is connected to the rotary joint 60. The rotary joint 60 is connected to the discharge side of a lubricating liquid supply source 64 having a lubricating liquid pressure-feeding function, and the lubricating liquid supplied from the lubricating liquid supply source 64 passes through the rotary joint means 60 to the lubricating liquid introducing pipe 46. Lubricating liquid flow path 46
It has been sent into a.

A part of the lubricating liquid flowing through the lubricating liquid introducing pipe 46 passes through a branch passage 46c which is a bearing lubricating passage branched in the radial direction at the position of the rotary bearing 18c, and through the draw bar 24 and the movable sleeve member 34. , Reaches an annular pocket 34b formed on the outer circumference of the movable sleeve member 34. After that, the lubricating liquid is further subjected to centrifugal force to further increase the radial hole 48 of the main shaft 14.
c, and is supplied into the rotary bearing 18c through the lubricating liquid passage 50c of the inner ring of the rotary bearing 18c. As a result, the rotary bearing 18c
Is subjected to underrace lubrication as well as being deprived of heat and cooled.
The pocket 34b described above is formed to be long in the axial direction. Therefore, even when the movable sleeve 34 moves forward and backward in the axial direction together with the drawbar 24, the lubricating liquid is reliably supplied from the pocket 34b to the rotary bearing 18c.

The lubricating liquid flow path 46a of the lubricating liquid introducing pipe 46
Is further extended forward, is branched in the radial direction at the front end of the lubricating liquid introducing pipe 46, and enters the inside of the guide sleeve 40 via a plurality of branch passages 46b radially passing through the drawbar 24 and the guide sleeve 40. The plurality of axial lubricating liquid flow passages 40a forming the formed first sub-lubricating liquid flow passage are communicated with each other.

The guide sleeve 40 communicates with the inside of the spring chamber 26 via a connecting passage 40b penetrating the inner end of the guide sleeve 40, that is, the spring seat surface of the spring 28. The above-mentioned plurality of lubricating liquid flow paths 40a in the axial direction are substantially the same as the front rotary bearing 18a,
The lubricating liquid flow passage 40a is provided in a region corresponding to the inner region of 18b at predetermined intervals or at equal intervals in the circumferential direction.
In addition, the radial holes 40c and 40d, which are bearing lubrication flow passages, are formed in a plurality of locations on the outer cylindrical wall of the guide sleeve 40.
Through the radial holes 48a, 48b formed in the wall of the main shaft 14 at positions facing both rotary bearings, and further, a plurality of lubricating liquid passages are formed in the inner rings of both rotary bearings 18a, 18b. The rotary bearings 18a, 18b are communicated with the rotary bearings 18a, 18b arranged in front of the rotary bearings 18a, 18b by centrifugal force during rotation of the main shaft 14 to under-race lubricate the rotary bearings 18a, 18b. 18b
It also takes away the heat generated during rotation and cools down. Bearing 1
Lubricating liquid passages 50a, 50b, 50c are drilled right below the ball raceways of the inner rings of 8a, 18b, 18c, but the rotating balls are pressed to the outer ring side by centrifugal force, and the lubricating liquid passages 50a, 50b are formed. , 50c and the balls are not in contact with each other, and there is no problem that noise is emitted from the bearings or the life is shortened.

On the other hand, the spring chamber 26 communicates with the lubricating liquid flow passage 46a of the lubricating liquid introduction pipe 46 via the communication flow passage 40b as described above, and the spring chamber 26 is further connected to the rear of the main shaft 14. On the end side, it communicates with a plurality of axial lubricating liquid flow passages 34a formed in the movable sleeve member 34 to form an axial core cooling flow passage, so that the lubricating liquid flows into this lubricating liquid flow passage 34a. . As described above, the lubricating liquid mainly flows from the rotary bearing 18a or the like during the rotation of the main shaft 14 while flowing through the lubricating liquid introducing pipe 46, the internal passages of the front and rear sleeves 40 and 34, and the spring chamber 26. It also acts to remove heat and heat generated from the drive motor from the inside and cool it.

Now, the movable sleeve 34 behind the main shaft 14
The lubricating liquid that has flowed into the lubricating liquid flow passage 34a is further provided at the rear end of the lubricating liquid flow passage 34a from the annular pocket 34c that is formed in the axial direction and is radially formed in the rear end wall of the main shaft 14. A radial flow passage 52a formed in a ring body 52 that is interposed and fixed between the rear end of the main shaft 14 and the rear portion of the housing 12 via the flow passage 48d, and the lubricating liquid flow passage 12a at the rear end of the housing 12. Through the external lubricating liquid line 54,
The rotary bearing 18 at the front part of the housing 12 passes through the sub-lubricant flow passage formed by the radial flow passage 48d, the radial flow passage 52a, the lubricating liquid flow passage 12a, the external lubricating liquid passage 54, and the like.
The annular flow passage 12b is formed in a spiral shape in the outer peripheral region of a and 18b and communicates with the annular flow passage 12b through the inflow port 54a.
The heat generated during the rotation of the rotary bearings 18a, 18b in the front part of 2 is taken to cool the front part region.

Also in this case, the pocket 34c is
Since it is formed long in the axial direction, the movable sleeve 3
Even when moving forward and backward in 4, the lubricating fluid must be surely in the radial flow path 48.
flow into the radial flow path 52a via d, and
There is no interruption in the circulation of the lubricating fluid to the front of the. In the present embodiment, the lubricating liquid that has flowed through the annular flow passage 12b and has cooled the outer peripheral area of the bearing in the front part of the housing 12 is further subjected to the annular flow provided in the housing 12 in the outer peripheral area of the stator M2 of the built-in motor. It also flows through the annular flow path 12c similar to the path 12b, and therefore takes the heat generated by the drive motor and also cools the housing portion in this area. Then, the lubricating liquid that has cooled the housing 12 in this way is collected from the discharge port 12d provided in a part of the housing 12 through the recovery conduit 5
5, the recovery pipe 55 further returns to the above-mentioned lubricating liquid supply source 64 having a liquid suction function via the return flow passage 56. The annular cooling channels 12b and 12c form a housing cooling channel. In the above-mentioned return conduit 56, the lubricating liquid recovery passage 12 in which the lubricating liquid after lubricating the front and rear rotary bearings 18a, 18b, 18c is also formed in the housing 12
It is recovered from e and the like through an external recovery conduit 58.

On the other hand, in this embodiment, the air passage 74 is formed from the air pressure source 70 through the air passage 72 to the bearing retainer 20 provided at the front end of the housing 12 and the front end of the main shaft.
The pressure air is jetted into the tapered hole-shaped mounting hole 16 through the formed radial passage 76, and the rotary bearings 18a and 18b.
Also, a configuration is provided in which an air curtain is formed to prevent the lubricating liquid supplied to the above from flowing out and leaking toward the mounting hole 16, and at the same time, the inside of the tapered mounting hole 16 is cleaned.

Similarly, from the pressurized air source 70 to the air passage 78,
The air flow ejected toward the rotor M1 via the air passage 80 penetrating the inside of the housing 12 and the stator M2 cools the rotor M1 and is discharged from the inside of the main shaft 14 to the outside through a gap. There is. Also in the rear end region of the main shaft 14, through the radial air passages 83 and 84 formed in the rear end region of the housing 12 from the external air passage 82 to both sides of the radial flow passage 52a of the annular body 52 for the lubricating liquid. It jets into the two formed annular air passages 86, 88, and flows radially from the lubricating liquid passage 34a of the rear movable sleeve 34 through the pocket 34c and the radial passage 48d of the main shaft 14 to the radial passage 52a. It has a structure to prevent the lubricating liquid from leaking to the outside of the rear end of the spindle by performing a leakage preventing action on the lubricating liquid by an air curtain action. The leakage of the lubricating liquid due to the air curtain action can be replaced with well-known oil sealing means if necessary, but sealing with the air curtain using pressurized air is installed at the machine tool processing site. It is convenient in that a compressed air source can be used, and it is non-contact and has the advantage that there is no friction or wear.

As is apparent from the above description, the main spindle device 10 according to the present embodiment lubricates the rotary bearing from the central region of the main spindle 14 of the main spindle device 10 using the lubricating liquid supplied from the lubricating liquid supply source 64. At the same time as supplying the liquid to perform lubrication, the lubricating liquid flow path is formed such that the housing 12 is the outermost sheath from the center of the spindle.
Since it is formed so as to bypass the heat retaining area around the rotary bearing holding portion in (1), the main shaft 14 and the housing 12 can be cooled in order. Moreover,
At this time, the lubricating liquid that has absorbed heat and warmed while cooling the members inside and inside the main shaft 14 is the outermost housing 12
Since it is circulated to the housing 12, and further heat is taken from the housing 12 and cooling is performed, the relatively cool lubricating liquid cools the inside of the spindle device 10 and the outside is cooled by the slightly heated lubricating liquid. No strong clamping force is exerted by the housing of the outer element holding the rotary bearing. As a result,
Even when the rotary bearings 18a, 18b, 18c rotate at a high speed, they do not cause seizure, and the advantage that the main shaft 14 can be rotated for a long time can be obtained.

The advantage of such a system in which the external cooling is relaxed more than the internal cooling is described in detail in Japanese Patent Application Laid-Open No. 4-25343 filed by the present applicant. This is different from the known configuration described above in that the above-mentioned advantages are also applied to the cooling action performed consistently with the lubricating action of the lubricating liquid. FIG. 2 shows a second embodiment of the present invention, in which a cutting fluid is circulated axially in the central region of the spindle of the spindle device from the rear end side to the front end side to penetrate a tool holder T mounted at the tip of the main spindle. Then, lubrication with the lubricating liquid according to the present invention is applied to a spindle device having a so-called spindle-through type cutting liquid supply mechanism capable of supplying a coolant such as cutting liquid or air to the cutting tool held by the tool holder T. In this embodiment, a mechanism for consistently achieving cooling is also incorporated.

Now, in this embodiment, a long and hollow cutting fluid introducing pipe 46A is fitted and disposed in the draw bar 24 at the center of the spindle 14 of the spindle device 10, and this cutting fluid introducing pipe 46A is provided.
Is projected to the rear end portion of the main spindle device 10 and coupled to the rotary joint 60A, and the rotary joint 60A is connected to the cutting fluid supply source 62 via an appropriate pipe line 60a. The cutting fluid flow passage 146 is introduced into the cutting fluid flow passage 146 at the center of the liquid introduction pipe 46A.
In the tip region of the draw bar 24, the cutting liquid flow path 148 that penetrates the taper shank S, the pull stud P, etc. of the tool holder T is supplied to the tip of the tool holder T. Therefore, this cutting fluid causes a tool (not shown) held by the tool holder T to be
It is possible to perform the cutting of the work while constantly supplying the cutting fluid from the central area of the tool.

Further, the draw bar 24 is advanced by being pressed by the tool attaching / detaching operation means provided on the rear end side of the main shaft 14, as in the embodiment shown in FIG. The ball 24a can be disengaged from the pull stud P, the tool holder T can be released and detached, and if the pulling action of the actuating means and the spring force of the return spring 28 of the spring chamber 26 pulls it back to the rear end side. The tool holding ball 24a is engaged with the pull stud P of the tool holder T so that the tool holder T is brought into close contact with and mounted in the mounting hole 16 at the tip of the main shaft 14.

The tool attaching / detaching operating means is a cylinder 30.
A, a piston 32A, and a hydraulic power source 90A. When the tool holder T is pulled out from the tool mounting hole 16, pressure oil is supplied to the cylinder 30A so that the piston 32A moves forward in the front direction of the spindle. Then, the piston 32A pushes the rear end of the draw bar 24, the draw bar 24 advances against the spring force of the return spring 28, and the engagement between the tool gripping ball 24a and the pull stud P is released. When the tool holder T is mounted, when the pressure oil is supplied in the direction in which the piston 32A is retracted, the draw bar 24 is retracted by the spring force of the return spring 28, so that the tool gripping ball 24a and the pull stud P are engaged. is there.

If the cutting fluid introducing pipe 46A is provided between the piston 32B and the cylinder 30B, it is constantly urged forward by a spring, and the front end face of the cutting fluid introducing pipe 46A is brought into close contact with the rear end face of the pull stud P and the cutting fluid is introduced. Will not leak. When the tool holder T is replaced by an automatic tool conversion device (not shown), the hydraulic source 90A is connected to the cylinder 3
The pressure oil is fed to 0B to retract the piston 32B, that is, the cutting fluid introducing pipe 46A is retracted and retracted, and the pull stud P is pulled.
The rear end face and the front end face of the cutting fluid introducing pipe 46A are prevented from colliding with each other. When the tool replacement is completed, the pressure oil to the cylinder 30B is drained, and the cutting fluid introduction pipe 46A and the pull stud P are brought into close contact with each other by the force of the spring provided in the cylinder 30B.

When the drawbar 24 is moved forward or backward,
A movable sleeve 134 attached by a fastening method such as screwing is provided on the rear end side of the draw bar 24, and the front end side of the movable sleeve 134 faces the spring chamber 26 and the return spring provided in the spring chamber 26. 28 seats are formed. The movable sleeve 134 integrally moves forward and backward when the drawbar 24 moves forward and backward, and compresses and accumulates the return spring 28 to accumulate return spring force when moving forward, and when returning with the drawbar 24, the return spring 28 returns. The return spring pressure accumulated in 28 acts on the draw bar 24 via the movable sleeve 134 to promote the return action.

On the other hand, in this embodiment, the cutting fluid introducing pipe 46A
A main lubricating liquid flow passage 146a, which forms a lubricating liquid supply flow passage, is provided between and the inner wall of the center hole of the draw bar 24. Lubricating liquid is supplied from the lubricating liquid supply source 64 to the main lubricating liquid passage 146a through a lubricating liquid introducing passage provided on the rear end side of the main shaft 14. That is, the same lubricating liquid introduction flow path is provided in the inlet pocket 134 formed in the movable sleeve 134.
a, a radial flow path 134b, a radial flow path 152a of the ring body 152 fixed to the rear end side of the housing 12, and a radial flow path 153 formed in the rear end side peripheral wall of the housing 12 in the radial direction. The lubricating liquid is supplied through the conduit 66 that is appropriately arranged in the above.

From the above-mentioned lubricating liquid introduction flow passage to the main lubricating liquid flow passage 14
A part of the lubricating liquid supplied into 6a is a branch passage 1 which is a bearing lubrication passage branched in the radial direction at the position of the rotary bearing 18c.
After passing through 47, through the movable sleeve 134, it reaches an annular pocket 134c formed on the outer periphery of the movable sleeve 134. After that, the lubricating liquid is further subjected to centrifugal force action, and further, the radial hole 155 of the main shaft 14 and the lubricating liquid passage 50 of the inner ring of the rotary bearing 18c.
It is supplied into the rotary bearing 18c through c. As a result, the rotary bearing 18c is under-race lubricated and heat is removed,
To be cooled. The above-mentioned pocket 134c is formed to be long in the axial direction, so that the movable sleeve 134 is attached to the drawbar 24.
At the same time, the lubricating liquid is reliably supplied from the pocket 134c to the rotary bearing 18c even when it moves back and forth in the axial direction.

Further, the lubricating liquid supplied into the main lubricating liquid passage 146a is drawn in the drawbar 2 in the front region of the main shaft 14.
4 and a guide sleeve 4 mounted in the tip region
A plurality of radial flow passages 1 formed by penetrating in the radial direction 0
Flows to 48. The plurality of radial flow paths 148 are formed in the guide sleeve 40 and are arranged in the inner regions of the rotary bearings 18a and 18b on the front side of the main shaft 14 to form a plurality of first sub-lubricant flow paths in the axial direction. Of the lubricating liquid flow passage 40a, and therefore the lubricating liquid flows through these lubricating liquid flow passages 40a.
flows into a.

The guide sleeve 40 communicates with the inside of the spring chamber 26 via a connecting passage 40b penetrating the inner end of the guide sleeve 40, that is, the spring seat surface of the spring 28. The above-mentioned plurality of lubricating liquid flow paths 40a in the axial direction are substantially the same as the front rotary bearing 18a,
The lubricating liquid flow passage 40a is provided in a region corresponding to the inner region of 18b at predetermined intervals or at equal intervals in the circumferential direction.
Further, the radial holes 40c and 40d, which are bearing lubrication passages formed at a plurality of locations on the outer cylindrical wall of the guide sleeve 40, are further provided.
Through the radial holes 48a, 48b formed in the wall of the main shaft 14 at positions facing both rotary bearings, and further, a plurality of lubricating liquid passages are formed in the inner rings of both rotary bearings 18a, 18b. The rotary bearings 18a, 18b are communicated with the rotary bearings 18a, 18b arranged in front of the rotary bearings 18a, 18b by centrifugal force during rotation of the main shaft 14 to under-race lubricate the rotary bearings 18a, 18b. 18b
It also takes away the heat generated during rotation and cools down.

On the other hand, the spring chamber 26 has a main lubricating liquid passage 146.
a through the communication flow path 40b, and the same spring chamber 2
6 is a rear end side of the main shaft 14, and a movable sleeve member 13
4 also communicates with the lubricating liquid flow path 154. The connecting flow passage 40b, the spring chamber 26, and the lubricating liquid flow passage 154 form a shaft cooling passage. It goes without saying that the lubricating liquid flowing in the spring chamber 26 thus heats and cools the main shaft 14 from the inside.

The lubricating liquid in the lubricating liquid flow passage 154 includes an annular flow passage 156 formed in the ring body 152, a radial flow passage 157, and a radial flow passage 1 formed in the housing 12.
2a, and similarly to the embodiment of FIG. 1 described above, flows to the front region of the housing 12 through an appropriate external conduit 54,
At the outer peripheral portion of the housing 12, it flows into the annular lubricating fluid flow passage 12b formed around the rotary bearings 18a and 18b, and heats and cools the front area of the housing 12. Further, the lubricating fluid flows from the annular lubricating fluid passage 12b to the periphery of the stator M2 of the drive motor, and cools the outer peripheral area of the drive motor of the housing 12 while flowing through the annular passage 12c.
It is recovered in the recovery conduit 56 from the liquid outlet 12d. The annular cooling channels 12b and 12c form a housing cooling channel. The rotary bearings 18a, 18b, 18c
The lubricating liquid that has been supplied to the housing and has performed a lubricating action is the housing 1
From the lubricating liquid recovery passage 12e formed in 2 to the recovery conduit 56 via the recovery conduit 58, the recovery conduit 56 returns the recovered lubricating liquid to the lubricating liquid supply source 64 again.

The pressure air supplied from the air pressure source 70 is passed through the air passage 72 to the bearing retainer 20 provided at the front end of the housing 12 in the tip end region of the main shaft 14 as in the embodiment shown in FIG. Pressure air is jetted into the tapered hole-shaped mounting hole 16 through the air passage 74 formed therethrough and the radial passage 76 formed so as to penetrate the front end of the main shaft, and the rotary bearing 1
The lubricating liquid supplied to 8a and 18b forms an air curtain for preventing the lubricating liquid from flowing out and leaking toward the mounting hole 16, and at the same time, the inside of the tapered mounting hole 16 is cleaned. .

Similarly, from the pressurized air source 70 to the air passage 78,
An air flow ejected toward the rotor M1 through an air passage 80 penetrating the inside of the housing 12 and the stator M2 cools the rotor M1 and is discharged from the inside of the main shaft 14 to the outside through a gap. In between, the rotary bearings 18b, 18
A pressure is applied to the lubricating liquid leaking from the c side to prevent the lubricating liquid from flowing into the drive motor.

Also in the rear end region of the main shaft 14, pressurized air is supplied from the air passage 82 to the required sealing portion from the radial air passages 160, 161, 162 formed in the housing 12 and the ring body 152. Forming a curtain,
The leakage of the lubricating liquid in the channel of the lubricating liquid is prevented. Of course, it goes without saying that the mechanism for preventing the leakage of the lubricating liquid by means of these air curtains may be replaced with a configuration in which a known oil ring is mounted at a required sealing position to seal the liquid.

As is apparent from the above description, in the spindle device 10 according to this embodiment shown in FIG.
Spindle 14 of the spindle device 10 using the lubricating liquid supplied from
At the same time as supplying the lubricating liquid from the central region of the rotary bearings 18a to 18c to perform the lubrication, the lubricating liquid flow path causes the lubricating liquid flow path to extend from the central portion of the main shaft to the heat retention region around the rotary bearing holding portion in the housing 12 of the outermost cover. Since the main shaft 14, the rotary bearings 18a to 18c, the housing 12 and the like can be sequentially cooled because they are detoured and formed, it is similar to the previous embodiment.

In addition, at this time, the lubricant that has absorbed a little heat and is warmed while cooling the inner and inner members of the main shaft 14 is circulated to the outermost housing 12, and the housing 1
Since the structure in which heat is further removed and cooled from 2 is used, the main shaft device 10 and the inside are cooled by a relatively cold lubricating liquid, and the outside is cooled by a slightly warmed lubricating liquid. No strong clamping force is exerted by the element housing. As a result, the rotary bearings 18a, 18b, 1
Even when the 8c rotates at a high speed, there is no case where they are seized, and it is possible to obtain an advantage that the main shaft 14 can be rotated for a long time.

In the two embodiments described above, the rotary bearing 1
8a and 18b, radial holes 40c, 40d, 48a and 48b and lubricating liquid passages 50 provided immediately below the raceway surfaces of the rolling elements.
Instead of a and 50b, a lubricating liquid passage is provided in the radial direction from the lubricating liquid passage 40a toward the spacer 19, and the lubricating liquid is supplied from the spacer 19 to the rolling elements of the left and right rotary bearings 18a and 18b. As described above, a lubricant passage may be formed in the spacer 19. Even in this case, the rotary bearing is well lubricated. Similarly, with respect to the rotary bearing 18c, a method may be used in which the lubricating liquid from the lubricating liquid flow paths 46a and 146a is supplied from the side via the nut 22 adjacent to the rotary bearing 18c, instead of underrace lubrication.

Further, in the above-described two embodiments, the lubricating oil that has been cooled to the rear of the main shaft after cooling the shaft core is immediately returned to the lubricating liquid supply source 64 without further circulating to the housing, and the lubricating liquid flow path 46a, 146a to the rotary bearings 18a, 18b,
The lubricating liquid supplied to 18c may be immediately returned to the lubricating liquid supply source 64 after circulating through the annular flow passages 12b and 12c without recovering the lubricating liquid in the recovery conduit 58 to cool the housing once. Of course, this method is used in combination with the method in which the lubricating liquid after cooling the core is further circulated in the housing,
After the housing is circulated, both may be collected and returned to the lubricating liquid supply source 64. The lubricating liquid supply source has a suction pump, a filter, and a lubricating liquid temperature adjusting device built-in, and a spring chamber 26
It is possible to filter the lubricating liquid mixed with dust by circulating it through such a way so that it can be supplied to the rotary bearing again, and adjust the lubricating liquid temperature so that the main spindle device can maintain the specified temperature. Circulate supply.

[0047]

According to the present invention, as is clear from the description of the above embodiment, the lubricating liquid supplied from the lubricating liquid supply source is caused to flow sequentially from the inside of the spindle device to the peripheral region, During this period, the rotary bearing that rotatably supports the main shaft is lubricated, and the internal region of the main shaft device is deprived of heat and cooled by a cold lubricating liquid. In addition, a method of absorbing heat and warming lubricating fluid that circulates inside the main spindle and circulates it to the housing to remove heat and cool the housing is adopted, so that lubrication and cooling can be achieved uniformly with the same lubricating fluid. , The spindle device is provided with an effective lubricating effect and cooling effect, and therefore, even when performing high-speed rotation,
It is possible to obtain smooth and stable spindle rotation for a long period of time. Further, even when the spindle through coolant device is incorporated in the main spindle, it is possible to obtain a main spindle device having similar lubricating and cooling effects. Further, an underlace lubrication system in which the lubricating liquid is supplied to the rolling elements from immediately below the raceway surface of the rolling elements of the rotary bearing can further enhance the lubrication and cooling effects.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a spindle device for machine tools according to the present invention.

FIG. 2 is a sectional view showing a second embodiment of a spindle device for machine tools according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Main shaft device 12 ... Housing 12a ... Radial flow path 12b, 12c ... Annular flow path 14 ... Main shaft 18a, 18b, 18c ... Rotating bearing 24 ... Drawbar 34 ... Movable sleeve member 34a ... Lubricating liquid flow path 40 ... Guide sleeve 40a ... Lubricating liquid flow path 40c, 40d ... Radial hole 46 ... Lubricating liquid introduction pipe 46a ... Lubricating liquid flow path 48a, 48b ... Radial hole 50a, 50b ... Lubricating liquid path 54 ... External conduit 56 ... Recovery conduit 64 ... Lubricating liquid supply source

Claims (6)

[Claims] 1. A spindle device of a machine tool, wherein a spindle is rotatably supported by a housing by a rotary bearing, and communicates with the center of the spindle from the rear of the spindle toward the front of the spindle, and is connected to the discharge side of a lubricating liquid supply source. A lubricating liquid supply flow path, a bearing lubricating flow path branched from the lubricating liquid supply flow path in the radial direction and opening toward the rotary bearing, and a branching from the lubricating liquid supply flow path in the main shaft. A shaft cooling passage for circulating a lubricating liquid along a peripheral surface to cool the inner surface of the main spindle, and a lubricating liquid connected from the bearing lubricating passage and the shaft cooling passage to the suction side of the lubricating liquid supply source. A spindle device for a machine tool, comprising: a recovery passage, and configured to perform both lubrication of the rotary bearing and cooling of the spindle of the spindle. 2. A spindle device of a machine tool, wherein a spindle is rotatably supported in a housing by a rotary bearing, and communicates with a central portion of the spindle from a rear side of the spindle toward a front side of the spindle and is connected to a discharge side of a lubricating liquid supply source. A lubricating liquid supply flow path, a bearing lubricating flow path branched from the lubricating liquid supply flow path in the radial direction and opening toward the rotary bearing, and a branching from the lubricating liquid supply flow path in the main shaft. A shaft cooling passage for circulating a lubricating liquid along a peripheral surface to cool the inner surface of the main shaft, and at least one of the lubricating liquid lubricated for the rotary bearing and the lubricating liquid cooled for the shaft. A housing cooling flow passage circulated in the housing, and a lubricating liquid recovery passage connected from the housing cooling flow passage to the suction side of the lubricating liquid supply source, for lubricating the rotary bearing and for cooling the spindle core. And the Hauge Spindle device of a machine tool, characterized by being configured to cool the grayed to perform together. 3. The spindle device for a machine tool according to claim 1, wherein the rotary bearing lubrication is underrace lubrication in which the bearing lubrication flow passage communicates with a lubricating liquid hole formed in an inner ring of the rotary bearing. . 4. A spindle device of a machine tool, wherein a spindle is rotatably supported by a housing by rotary bearings which are spaced apart from each other in the axial front-rear position, and a spindle is rotatably supported in a central portion of the spindle from the rear of the spindle toward the front of the spindle. A lubricating liquid supply channel connected to the discharge side of the lubricating liquid supply source and a lubricating liquid that is branched in the radial direction at the front and rear positions of the lubricating liquid supply channel and is bored in the inner ring of each rotary bearing. A bearing lubrication flow path communicating with the hole and underlacing each of the rotary bearings, and folded back from the spindle front side of the lubricating liquid supply flow path, and the lubricating fluid is circulated to the spindle rear side along the spindle inner peripheral surface. A shaft cooling passage that cools the inner surface of the spindle, a housing cooling passage that is provided in the housing and that communicates with the spindle cooling passage on the rear side of the spindle, and supplies the bearing lubricating passage to the rotary bearing. Lubricated liquid A lubricating liquid recovery passage connected to the suction side of the lubricating liquid supply source for collecting the lubricating liquid that has flowed through the housing cooling flow passage, lubrication of the rotary bearing, cooling of the main shaft, and cooling of the main shaft. A spindle device for machine tools, characterized in that the housing is also cooled. 5. The lubricating liquid supply flow path is a pipe path provided axially in a draw bar inserted in the main shaft, and the shaft core cooling flow path includes the inner peripheral surface of the main shaft and the draw bar. An annular gap formed between the outer peripheral surface and the outer peripheral surface.
A spindle device for a machine tool according to any one of items 1 to 4. 6. The lubricating liquid supply passage is an annular gap formed between an inner peripheral surface of a draw bar inserted in the main shaft and an outer peripheral surface of a coolant introduction pipe inserted in the draw bar, The spindle device for a machine tool according to any one of claims 1 to 4, wherein the shaft core cooling flow path is an annular gap formed between an inner peripheral surface of the main shaft and an outer peripheral surface of the draw bar.