JP3452352B2 - Rotary axis device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuuming device having a suction portion on the rotary shaft side and other rotary shaft devices.

[0002]

2. Description of the Related Art For example, in a processing machine for processing a work such as a small-diameter disk while rotating it, or a cleaning machine for cleaning while rotating the work, the work is attached to one end of a rotary shaft so that the work can be easily attached and detached. An evacuation device equipped with a suction unit is used.

Conventionally, this type of vacuuming device rotatably supports a rotary shaft having an adsorption portion at its upper end by a housing via a pair of upper and lower rolling bearings, and a suction passage communicating with the adsorption portion on the rotation shaft. A suction passage connected to the vacuum source side between the two rolling bearings of the housing, and a suction passage on the rotating shaft side and a suction passage on the housing side between the upper and lower rolling bearings on the inner diameter side of the housing. A communication passage is provided to communicate with each other, and an oil seal is
Other contact seals are provided.

[0004]

In the conventional vacuum evacuation device, contact type seals are provided on both upper and lower sides of the communication passage, and the contact type seals prevent atmospheric air from entering from the rolling bearing side to the communication passage side. I am trying.

However, when the rotating shaft rotates at a high speed of about 8000 to 10000 times / minute, in a contact type seal such as an oil seal, heat generation due to frictional heat of the contact portion is remarkable and the seal life is very short. Become. Therefore, stable sealing performance cannot be maintained for a long period of time,
There is a problem that the contact type seal needs to be replaced in a short period of time.

In view of such conventional problems, the present invention has been made.
An object of the present invention is to provide a rotary shaft device that can continuously maintain stable sealing performance for a long period of time, has a simple structure, can be easily manufactured at low cost, and can be easily replaced and maintained.

[0007]

The present invention has a suction section.
A vertical rotation shaft, a housing that rotatably supports the rotation shaft through at least a pair of upper and lower bearings, a vacuum suction passage formed in the rotation shaft and communicating with the adsorption portion, and formed between both housing bearings. True and connected to a vacuum source
Sinking a passage respectively provided, between both bearing inner diameter side of the housing, the rotary shaft system provided with a communication passage communicating the two evacuation passage, on both upper and lower sides of and communication passage between both bearings, the rotation shaft side and comprising a labyrinth seal for sealing between the housing side, between the both labyrinth seal, true rotary shaft side
The sump part that collects the liquid from the emptying passage and the sump part
From the through hole in the bottom wall to the liquid through the vacuum suction passage on the housing side.
Communication passage that connects both vacuum suction passages so that they can be collected outside
And are provided .

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, each embodiment of the present invention will be described in detail with reference to the drawings.

1 and 2 illustrate a first embodiment of the present invention. In FIG. 1, W is a work such as a small-diameter disk, 1 is a vacuuming device as a rotary shaft device, a processing machine,
It is built into a washing machine.

The evacuation device 1 has a vertical rotating shaft 2
A suction part 3 provided on the upper end side of the rotating shaft 2 for removably adsorbing the work W by vacuuming, and a housing 5 for rotatably supporting the rotating shaft 2 via a pair of upper and lower rolling bearings 4. The rotary shaft 2 is provided with a fluid passage 6 communicating with the adsorption portion 3, and the housing 5 is provided with a fluid passage 7 connected to a vacuum source (not shown), and between the rotary shaft 2 and the housing 5. A communication passage 8 that connects the fluid passage 6 and the fluid passage 7 and labyrinth seals 9 arranged on both upper and lower sides of the communication passage 8 are provided.

The suction part 3 has a suction recess 10 formed substantially concentrically at the center on the upper surface side and is detachably fixed by a fixing bolt 11 or the like on the upper end side of the rotary shaft 2. Rotating shaft 2
Is located at the center of the upper side of the suction part recess 10 of the suction part 3.
Is formed in the axial direction, and the lower end side is connected to a drive source (not shown) so that it can be rotationally driven at high speed.

The housing 5 is fixed to a predetermined support frame 12 side so as to project upward from the support frame 12.
In the housing 5, a fluid passage 7 is formed at a substantially central portion between the upper and lower rolling bearings 4 so as to penetrate therethrough in the radial direction. The rolling bearing 4 is, for example, a ball bearing or the like, in which a large number of balls 15 are interposed between the outer ring 13 and the inner ring 14, and a vertical gap is provided between the housing 5 and the rotating shaft 2. Is intervened in.

The inner ring 14 of each rolling bearing 4 is detachably fitted onto the small-diameter portion 16 of the rotary shaft 2, and at the upper and lower steps of the large-diameter portion 17 of the rotary shaft 2 and the small-diameter portion 16 side. It is fixed via an inner ring pressing body 19 with the fixed nut 18 screwed together. The outer ring 13 of each rolling bearing 4 is fitted to the inner diameter side of the housing 5, and the outer ring spacers 21 and 22 interposed between the upper and lower outer rings 13 and the outer ring retainers fixed to the upper and lower ends of the housing 5 are also provided. It is fixed by the body 20.

The inner diameter side of the housing 5 has substantially the same diameter in the vertical direction over the upper and lower rolling bearings 4, and the outer ring 13, the outer ring spacers 21, 22 and the outer ring of each rolling bearing 4 are arranged on the inner diameter side. The pressing body 20 is detachably fitted. The outer ring retainer 20 has its flange portions removably fixed to the upper and lower end surfaces of the housing 5 with bolts or the like. It should be noted that there is a minute gap between the outer diameter surface of the inner ring retainer 19 and the inner diameter surface of the outer ring retainer 20, and they are relatively rotatable in a non-contact state.

The outer ring spacers 21 and 22 are formed of upper and lower rolling bearings 4
There is one or a plurality, for example, three between them, and a communication passage 8 is formed in the outer ring spacer 21 at the center thereof. The communication passage 8 includes a peripheral groove 23 on the inner diameter side of the outer ring spacer 21 and the peripheral groove 23.
And a through hole 24 in the radial direction communicating with the fluid passage 7 side. The communication passage 8 is composed of the upper and lower rolling bearings 4.
It is located approximately in the center of the space.

A labyrinth seal 9 is provided on each of the upper and lower outer ring spacers 22 on the inner diameter side thereof. The labyrinth seal 9 is for sealing between the rotating shaft 2 side and the housing 5 side between the upper and lower rolling bearings 4 and both upper and lower sides of the communication passage 8, and as shown in FIG. The diaphragm wall 25 is integrally formed on the inner diameter side of the spacer 22 and the sealing surface 29 on the outer diameter side of the large diameter portion 17 of the rotary shaft 2.

A plurality of diaphragm walls 25 are provided in the vertical direction of the outer ring spacer 22 at predetermined intervals (for example, substantially equal intervals). Therefore, the diaphragm wall 25 is provided on the inner diameter side of the outer ring spacer 22. 25 and recesses 26 are formed alternately in the vertical direction.

Each throttle wall 25 has a trapezoidal cross-section with a reduced axial dimension on the inner diameter side, is formed in an annular shape continuously in the circumferential direction, and has an inner side surface 27 close to the communication passage 8 and The inclination angle of the outer side surface 28 opposite to the diametrical direction is set so that the atmosphere from each rolling bearing 4 side is difficult to enter.
The outer surface 28 is smaller than 27. Therefore,
The cross-sectional shape of the outer ring spacer 22 on the inner diameter side is formed into a substantially saw-tooth shape as a whole by a plurality of diaphragm walls 25 so that the outside surface 28 thereof prevents the entry of the atmosphere.

The gap between the inner diameter of each throttle wall 25 on the inner end side and the outer diameter of the seal surface 29 on the rotary shaft 2 side is, for example, 0.02 in diameter.
The gap is about 0.05 mm. The sealing surface 29 is a smooth surface.

A sealing material 30 such as an O-ring is provided on the outer diameter side of the upper and lower outer ring spacers 22, and the inner ring side of the housing 5 and the outer diameter side of the outer ring spacers 21 and 22 are provided by this sealing material 30. The space between and is sealed.

In the vacuum evacuation device 1 having the above structure, the work W
When attaching the to the suction part 3 on the rotary shaft 2,
If 7 is connected to a vacuum source with a control valve, etc.,
Since the inside becomes a negative pressure due to the evacuation of the vacuum source, the work W placed on it can be adsorbed and fixed by the adsorbing part 3. When removing the work W, the vacuum can be released by a control valve or the like.

Therefore, the work W is attached to the suction part 3 on the rotary shaft 2.
Even when the workpiece W is mounted and the workpiece W is subjected to predetermined processing, cleaning, and the like while being rotated at high speed around the rotary shaft 2, the workpiece W can be easily and surely attached to and detached from the suction portion 3.

The rotary shaft 2 is rotatably supported by the housing 5 via the upper and lower rolling bearings 4, and during the adsorption of the workpiece W, the rotary shaft 2 is connected via the communication passage 8 between the housing 5 and the rotary shaft 2. The fluid passage 7 on the housing 5 side and the fluid passage 6 on the rotating shaft 2 side communicate with each other to perform vacuuming.

In this case, since there are labyrinth seals 9 on both the upper and lower sides of the communication passage 8, the labyrinth seals 9 can seal between the housing 5 side and the rotary shaft 2 side.
Atmosphere can be prevented from entering the communication passage 8 from each rolling bearing 4 side.

Further, since the non-contact type labyrinth seal 9 is adopted, problems such as heat generation and abrasion of the seal portion due to frictional heat do not occur as compared with the case where a conventional contact type seal is used. Therefore, the durability is remarkably improved, stable sealing performance can be continuously maintained for a long time, and the number of maintenance such as inspection and replacement of the seal can be minimized.

Moreover, the labyrinth seal 9 is provided with an outer ring spacer 22 arranged between the outer rings 13 of the upper and lower rolling bearings 4 and a diaphragm wall.
25 are integrally formed, and the outer ring spacer 22 is attached to the labyrinth seal 9
Since it also serves as a labyrinth seal 9, there is no need for a dedicated member for the labyrinth seal 9, which simplifies the structure, and when performing maintenance such as inspection and replacement of the labyrinth seal 9, the outer ring spacer 21 It can be done easily by attaching and detaching 22,22. Since the outer ring spacers 21 and 22 are divided into the communication passage 8 and the labyrinth seal 9, they can be easily processed.

The labyrinth seal 9 has a plurality of throttle walls 25 in the axial direction of the rotary shaft 2, and the gap between the inner diameter of the throttle wall 25 and the outer diameter of the seal surface 29 on the rotary shaft 2 side is very small. In addition, the inclination angle of the outer side surface 28 is set to be closer to a right angle with respect to the axial direction than the inner side surface 27 of each diaphragm wall 25, and the cross-sectional shape including the plurality of diaphragm walls 25 is formed into a sawtooth shape. Therefore, it is possible to prevent the invasion of the atmosphere from the labyrinth seal 9 as much as possible, and to secure a sufficient sealing performance.

FIG. 3 illustrates a second embodiment of the present invention,
The outer surface 28 of the diaphragm wall 25 is substantially parallel to the diametrical direction of the rotary shaft 2, that is, substantially perpendicular to the axial direction of the rotary shaft 2.
In this case, the outer surface 28 of the throttle wall 25 has an advantage of further increasing the flow resistance when the atmosphere enters and improving the sealing performance of the labyrinth seal 9.

FIG. 4 illustrates a third embodiment of the present invention,
The outer surface 28 of the diaphragm wall 25 is inclined in the same direction as the inner surface 27. In this case, the inner diameter side of each throttle wall 25 itself is inclined outward in the axial direction of the rotary shaft 2.

Therefore, as shown by the arrow in FIG. 4, even if there is atmospheric air entering along the inner surface 27 of the outer diaphragm wall 25,
When passing through the inner diaphragm wall 25, the inner outer surface 28
A part will circulate in the recess 26 between the outer and inner surface 27. Therefore, in this case, the atmosphere cannot enter the communication passage 8 side unless it passes through the throttle walls 25 that are inclined outward, so that the sealing performance of the labyrinth seal 9 is further improved.

FIG. 5 illustrates a fourth embodiment of the present invention. In this embodiment, there is one outer ring spacer 21 between the upper and lower rolling bearings 4, and a circumferential groove 23 is formed substantially at the center of the inner ring side of the outer ring spacer 21 in the axial direction. On diaphragm wall 25
Are formed respectively. On the other hand, on the outer diameter side of the large diameter portion 17 of the rotary shaft 2, a circumferential groove 31 and a throttle wall 32 are formed so as to face the circumferential groove 23 and the throttle wall 25 of the outer ring spacer 21. The two peripheral grooves 23 and 31 form a communication passage 8, and the throttle walls 25 and 32 on both sides thereof form each labyrinth seal 9.

Thus, the diaphragm wall 2 of the labyrinth seal 9
5,32 may be provided on the inner diameter side of the outer ring spacer 21 and on the outer diameter side of the rotary shaft 2. The outer ring spacer 21 is not limited to one, but may be a plurality of two or more, each of which may be divided into the communication passage 8 and the labyrinth seal 9.

FIG. 6 illustrates a fifth embodiment of the present invention. In this embodiment, the inner ring spacer 33 corresponding to the space between the inner rings 14 of the upper and lower rolling bearings 4 is fitted onto the outer diameter side of the large diameter portion 17 of the rotary shaft 2, and the inner ring spacer 33 is On the outer diameter side,
A peripheral groove corresponding to the peripheral groove 23 of the outer ring spacer 21 and the diaphragm wall 25, respectively.
31 and a diaphragm wall 32 are provided.

Between the outer ring spacer 21 and the inner ring spacer 33, there are provided a communication passage 8 formed by the circumferential grooves 23, 31 and a labyrinth seal 9 formed by the throttle walls 25, 32. A seal member 34 such as an O-ring seals between the inner diameter side of the inner ring spacer 33 and the outer diameter side of the rotary shaft 2.

In this way, the spacer for the inner ring is attached to the outer diameter side of the rotary shaft 2.
The communication passage 8 and the labyrinth seal 9 may be provided between the inner ring spacer 33 and the outer ring spacer 21 by fitting the inner ring spacer 33.

In this embodiment, the inner ring spacer 33 is fitted over the large diameter portion 17 of the rotary shaft 2, but the large diameter portion 17 may be omitted depending on the fixing structure of the upper and lower rolling bearings 4. Rotation axis
It is also possible to fit the inner ring spacer 33 directly on the outer diameter side of 2 and regulate the distance between the inner rings 14 of the upper and lower rolling bearings 4 by this inner ring spacer 33.

The outer ring spacer 21 is omitted and the housing is omitted.
A step portion that restricts the outer ring 13 side of the rolling bearing 4 is provided on the inner diameter side of 5, and the inner diameter side of the housing 5 serves as a smooth sealing surface, and the throttle wall 32 of the inner ring spacer 33 and the sealing surface on the housing 5 side. The labyrinth seal 9 may be constituted by and.

FIG. 7 illustrates a sixth embodiment of the present invention,
Between the upper and lower rolling bearings 4, the vacuum evacuation passage 36 on the rotary shaft 2 side
It is equipped with a reservoir 38 that stores the liquid from the chamber, and a communication passage 39 that connects the vacuum suction passage 36 on the rotating shaft 2 side and the vacuum suction passage 37 on the housing 5 side so that the liquid in the reservoir 38 can be collected. is there.

The rotating shaft 2 is provided with an upper large-diameter portion 41 and a lower small-diameter portion 42 between the upper and lower rolling bearings 4 via a step portion 40, and a vacuum suction passage 36 is provided in the vicinity of the upper portion of the step portion 40. A through hole 36a on the lower end side is provided in the radial direction. Further, on the inner diameter side of the housing 5, an outer ring spacer 21 corresponding to the upper large diameter portion 41 and the lower small diameter portion 42 is provided with the step portion 40 interposed therebetween. The outer ring spacer 21 is integrally formed with the reservoir portion 38. Is formed in.

The outer ring spacer 21 has an outer peripheral wall portion 43 corresponding to the through hole 36a with a predetermined distance from the outer diameter side of the upper large diameter portion 41.
And an inner peripheral wall portion 44 located near the outer diameter side of the lower small diameter portion 42 near the lower side of the step portion 40, and an outer peripheral wall portion 43 and a bottom wall portion 45 between the inner peripheral wall portion 44, which are integrally provided. The outer peripheral wall portion 43, the inner peripheral wall portion 44, and the bottom wall portion 45 form a reservoir portion 38.

A housing is provided below the outer ring spacer 21.
A peripheral groove 46 communicating with the vacuum evacuation passage 37 of 5 is formed below the bottom wall portion 45 of the reservoir 38, and a through hole 47 vertically connecting the peripheral groove 46 and the reservoir 38 has a bottom wall 45. Is formed in.

Therefore, the reservoir portion 38, the through hole 47, and the circumferential groove 46 form a communication passage 39 that connects the vacuum evacuation passage 36 on the rotating shaft 2 side and the vacuum evacuation passage 37 on the housing 5 side, In addition, when vacuuming, the through hole 47, the circumferential groove 46 through the reservoir
The liquid in 38 can be collected in the vacuum passage 37 side.

A seal member 48 such as an O-ring is provided on the lower end side of the outer ring spacer 21. Also, the upper large diameter part 41 and the lower small diameter part
On the outer diameter side of 42, seal faces 41a, 42 for the labyrinth seal 9
a is formed. The evacuation passage 36 corresponds to the fluid passage 6 in FIG. 1, the evacuation passage 37 corresponds to the fluid passage 7, and the other configurations are substantially the same as those in FIG.

In this type of vacuuming apparatus 1, the work
If liquid such as cooling liquid or cleaning liquid is supplied to the W side,
When W is attracted to the adsorption part 3 by evacuation, the liquid in the adsorption recess 10 passes through the evacuation passage 36 and the upper and lower rolling bearings.
4 may enter between the rotary shaft 2 and the housing 5, or the liquid accumulated in the suction recess 10 may enter through the vacuum passage 36 due to natural flow.

However, in this embodiment, the vacuum evacuation passage is used.
Since the reservoir 38 is provided corresponding to the lower end of 36, even if the liquid may enter from the vacuum passage 36, the liquid can be captured and retained in the reservoir 38, Liquid does not flow to the lower rolling bearing 4 side. Therefore, it is possible to solve the problem that a lubricant such as grease of the lower rolling bearing 4 flows due to the liquid entering from the vacuum passage 36, and the lubricity of the lower rolling bearing 4 can be maintained.

The liquid accumulated in the reservoir 38 can be easily recovered to the outside from the vacuum passage 37 of the housing 5 through the through hole 47 and the circumferential groove 46 by vacuuming. Because of this
There is no problem such that the liquid accumulated in 38 overflows from the reservoir 38.

Particularly, in the outer peripheral wall portion 43, the through hole 36 of the evacuation passage 36 is formed.
Since it surrounds a, even if the liquid from the through hole 36a is scattered by the centrifugal force when the rotary shaft 2 rotates, the liquid droplets can be received by the outer peripheral wall 43 and guided to the pool 38. Further, since the inner peripheral wall portion 44 is below the step portion 40 at the lower end of the upper large diameter portion 41, the liquid dripping from the upper large diameter portion 41 side can be reliably received by the reservoir portion 38.

In this embodiment, the intermediate outer ring spacer 21 is provided with the pool portion 38, and the upper and lower outer ring spacers 22 are provided with the labyrinth seals 9.
21 and 22 may be integrally formed, or the intermediate outer ring spacer 21
The upper and lower outer ring spacers 22 may be integrated with each other.

The reservoir 38 may be integrally formed on the inner diameter side of the housing 5 instead of being provided on the outer race spacer 21. Therefore, it is sufficient that the reservoir 38 is fixed at least on the inner diameter side of the housing 5, and it does not matter whether or not the reservoir 38 is provided integrally with the housing 5.

When the reservoir 38 is provided integrally with the housing 5, the through hole 47 of the bottom wall 45 of the reservoir 38 constitutes a part of the vacuum suction passage 7 on the housing 5 side, and the reservoir
The space above 38 constitutes the communication path 39.
In addition, make sure that the housing is connected to the bottom of the reservoir 38.
The vacuum evacuation passage 37 may be formed in the radial direction 5.

FIG. 8 employs a staggered labyrinth seal 9, which can be similarly implemented. In FIG. 8A, the throttle wall 25 of the outer ring spacer 22 is in the recess 35 of the inner ring spacer 33, and the throttle wall 32 of the inner ring spacer 33 is in the outer ring spacer 33.
Corresponding to the concave portions 26 of 22 respectively. And each diaphragm wall 25,3
The axial thickness of 2 is almost the same.

FIG. 8B shows the diaphragm wall of the outer ring spacer 22.
25 in the recess 35 of the inner ring spacer 33, and the throttle wall 32 of the inner ring spacer 33.
Correspond to the recesses 26 of the outer ring spacer 22 respectively. And
Regarding the axial thickness of each of the diaphragm walls 25, 32, the diaphragm wall 25 of the outer ring spacer 22 is thin and the diaphragm wall 32 of the inner ring spacer 33 is thick. The thickness of each diaphragm wall 25, 32 may be reversed.

As described above, the labyrinth seal 9 may be of a staggered type in which the diaphragm wall 25 of the outer ring spacer 22 and the diaphragm wall 32 of the inner ring spacer 33 are alternately provided in the axial direction. .
In this case, the diaphragm wall 25 of the outer ring spacer 22 and the inner ring spacer 33
Since the flow path between the labyrinth seal 9 and the throttle wall 32 becomes a zigzag labyrinth, the sealing performance of each labyrinth seal 9 is further improved.

The outer diameter of the diaphragm wall 32 of the inner ring spacer 33 is
The diameter is slightly smaller than the inner diameter of the throttle wall 25 of the outer ring spacer 22. As a result, the inner ring spacer 33 can be inserted into the outer ring spacer 22 in the axial direction, and assembly, disassembly, and the like can be easily performed.

In this embodiment, an outer ring spacer 22 is provided on the inner diameter side of the housing 5, and an inner ring spacer 33 is provided on the outer diameter side of the rotary shaft 2, and throttle walls 25 and 32 are formed on these. However, one of the outer ring spacer 22 and the inner ring spacer 33 is omitted, and the throttle wall 25 or the throttle wall 32 on the omitted side is integrated with the inner diameter side of the housing 5 or the outer diameter side of the rotary shaft 2. It may be formed in.

Although the embodiment of the present invention has been described in detail above, the present invention is not limited to this embodiment.
Various modifications can be made without departing from the spirit of the present invention. For example, in FIGS. 5 and 6, both inner and outer side surfaces of the diaphragm walls 25 and 32 are substantially perpendicular to the axial direction of the rotary shaft 2, but the sectional shapes as shown in FIGS. good.

As long as the diaphragm walls 25 and 32 can be machined, the distal end side has an L-shaped cross section in which the tip side bends outward in the axial direction, the distal end side has a T-shaped cross section in which the tip side projects to both axial sides, or It is also possible to have a special cross-sectional shape such as an S shape.

Further, in the embodiment, the vacuuming device 1 used for the processing machine, the washing machine and the like is illustrated, but the use is not limited to the processing machine, the washing machine and the like, and the rotary shaft 2 is used.
Adsorption part on the tip side, middle side, and other appropriate places in the axial direction of
It goes without saying that if it has 3, it can be adopted for all of them.

Further, the vacuum evacuation device 1 of the embodiment has a rotary shaft.
Although the vertical type in which 2 is arranged in the vertical direction is illustrated, the present invention is not limited to the vertical type, and for example, the rotating shaft 2 may be arranged in the horizontal direction or may be arranged in an oblique direction. Therefore, it can be applied to various types such as a horizontal type, an obliquely inclined type and the like.

In the embodiment, the evacuation device 1 is exemplified, but the compressed gas may be sent through the fluid passages 6, 7 and the communication passage 8 or the liquid may be sent. good. Therefore, the present invention can be applied to devices other than the evacuation device 1. When sending a pressurized fluid such as compressed gas through the fluid passages 6, 7 and the communication passage 8, it is effective to reverse the direction of the throttle wall 25 of the labyrinth seal 9.

The rolling bearing 4 is not a ball bearing,
For example, roller bearings may be used. Rolling bearing
4 should be at least two in the axial direction of the rotary shaft 2, and 3
The rotary shaft 2 may be supported via one or more rolling bearings 4. A sliding bearing may be used instead of the rolling bearing 4.

[0062]

According to the present invention, since the labyrinth seals for sealing between the rotary shaft side and the housing side are provided between both bearings and on both upper and lower sides of the communication passage, the conventional contact type seal is used. Compared with the case of performing the above, there is an advantage that stable sealing performance can be continuously maintained for a long period of time, and the structure is simple, easy and inexpensive to manufacture, and replacement and other maintenance can be easily performed. Also both labyrinth sea
Reservoir for collecting liquid from the vacuum suction passage on the rotating shaft side
The liquid in the reservoir and the reservoir is drained from the through hole in the bottom wall.
It can be collected outside via a vacuum passage on the vacuum side.
Since there is a communication passage that connects the passages,
Even if there is liquid that enters through the vacuum passage, that liquid
This does not impair the lubricity of the bearing. Further, since the throttle wall of the labyrinth seal is provided in the spacer between both bearings, a member dedicated to the labyrinth seal is not required and the structure can be simplified.

[0063] Further between both bearings, only set a spacer for spacer and labyrinth seals for communication passage, the latter spacer, since the form a plurality of aperture wall constituting a labyrinth seal in the vertical direction The machining of each spacer is easy, and each spacer can be individually replaced if necessary.

Further, the outer ring spacer on the inner diameter side of the housing is
Since a plurality of throttle walls are provided in the downward direction, the outer diameter side of the rotary shaft is a smooth seal surface, and the labyrinth seal is constituted by the throttle wall and the seal surface, the labyrinth seal structure can be simplified. Since each throttle wall of the labyrinth seal is formed in a sawtooth shape, the sealing performance of the labyrinth seal is improved.

[0065] Also since the provided reservoir during seat for the outer ring between both the bearings, the structure can be simplified.

[Brief description of drawings]

FIG. 1 is a sectional view of an evacuation device showing a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part showing the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of a main part showing a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of a main part showing a third embodiment of the present invention.

FIG. 5 is a cross-sectional view of an essential part showing a fourth embodiment of the present invention.

FIG. 6 is a cross-sectional view of a main part showing a fifth embodiment of the present invention.

FIG. 7 is a cross-sectional view of a main part showing a sixth embodiment of the present invention.

8 (A) and 8 (B) are cross-sectional views of essential parts showing a staggered labyrinth seal of the present invention.

[Explanation of symbols]

2 rotation axis 3 Adsorption part 4 Rolling bearing 5 housing 6,7 fluid passage 8 passages 9 Labyrinth seal 21,22 Outer ring spacer 25,32 diaphragm wall 29 Sealing surface 33 Inner ring spacer 36,37 Vacuum passage 38 Pool 39 passage

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masao Harada 1661-1 Matsunokijima-cho, Wako-shi, Saitama Inside Harada Manufacturing Co., Ltd. (56) Reference JP-A-5-227696 (JP, A) JP-A-8-111956 (JP, A) JP 60-32324 (JP, A) JP 11-163106 (JP, A) Actual development Sho 58-80138 (JP, U) (58) Fields investigated (Int. Cl. ⁷⁾ , DB name) F16C 33/80 B23Q 3/08 F16J 15/447 H01L 21/304 651 B23Q 11/00

Claims (6)

(57) [Claims] 1. A vertical rotating shaft having an adsorption portion, a housing rotatably supporting the rotating shaft via at least a pair of upper and lower bearings, and a front shaft formed on the rotating shaft.
A vacuum evacuation passage communicating with the suction part and a vacuum evacuation formed between the both bearings of the housing and connected to a vacuum source.
Comprising respectively a can path, between the two bearing inner diameter side of the housing, the rotary shaft system provided with a communication passage communicating the two evacuation passage, on both upper and lower sides of and the communication passage between the two bearing Between the rotary shaft side and the housing side
Includes a labyrinth seal for sealing a both said labyrinth
Between the seals, liquid from the vacuum passage on the rotary shaft side
A pool part that stores the body and the liquid in the pool part of the bottom wall
Through the vacuum passage on the housing side from the through hole to the outside
Communication that connects the two vacuum passages so that they can be collected
A rotary shaft device having a path . 2. The rotary shaft device according to claim 1, wherein a throttle wall of the labyrinth seal is provided in a spacer between the bearings. Between wherein the dual-bearing, the only set a spacer for said labyrinth seal and spacer for communication passage, in the latter spacer, a plurality of diaphragm walls constituting the labyrinth seal in the vertical direction The rotary shaft device according to claim 1 or 2, wherein the rotary shaft device is formed individually. 4. The outer ring spacer on the inner diameter side of the housing is provided with a plurality of the diaphragm walls in the vertical direction, and the outer diameter side of the rotating shaft serves as a smooth seal surface, and the diaphragm wall and the seal surface are formed. The rotary shaft device according to claim 2 or 3 , wherein the labyrinth seal is configured by the following. 5. An outer ring spacer on the inner diameter side of the housing
The rotary shaft device according to any one of claims 1 to 4, wherein the pool portion is provided. 6. A large diameter between the two bearings of the rotary shaft
A step portion between the lower portion and the lower small diameter portion, and the step portion
Near the upper side of the lower end of the vacuum passage on the rotating shaft side.
Side through hole, and the outer ring spacer on the inner diameter side of the housing.
At a predetermined distance from the outer diameter side of the upper large diameter portion.
An outer peripheral wall portion corresponding to the through hole of the vacuum evacuation passage;
Located near the outer side of the lower small diameter part near the lower side of the step
An inner peripheral wall portion and a bottom between the outer peripheral wall portion and the inner peripheral wall portion
A wall portion integrally provided, and the outer peripheral wall portion, the inner peripheral wall portion and the front
The rotary shaft device according to any one of claims 1 to 5, wherein the reservoir portion is formed by the bottom wall portion .