WO2015128906A1 - Oil supply component for screw exhaust pump, and screw exhaust pump provided with said component - Google Patents

Abstract

　Provided are: an oil supply component for a screw exhaust pump, which makes it possible to realize a screw exhaust pump that can operate without maintenance over a long period of time and from a low-speed rotation range to a high-speed rotation range; and a screw exhaust pump provided with this component. The pump has a helical structural body disposed inside a rotating shaft of the pump, the helical structural body being capable of exhibiting a liquid-pumping function, and the structural body is configured from a driveable helical structural body positioned below the rotating shaft and a fixed helical structural body positioned thereabove.

Description

Oil supply part for screw exhaust pump and screw exhaust pump provided with the parts

The present invention relates to an oil supply component for a screw exhaust pump and a screw exhaust pump equipped with the component.

In general, in manufacturing equipment and production systems for manufacturing functional devices such as semiconductor devices, display devices using liquid crystal or organic EL, solar cell devices, and the like, a wide variety of pumps are used due to the limitation of application range due to pump performance. Used a lot.
On the other hand, for example, screw exhaust pumps of the type disclosed in Patent Documents 1 to 3 can exhaust in a wide range from a molecular flow region to a viscous flow region, and the exhaust performance does not depend on the type of exhaust gas. For this reason, it is complicated to change the pump for each gas type, replace the pump in response to changes in pressure conditions, and prepare a pump suitable for each discharge location in a production system having a plurality of discharge locations. There is nothing.
The same type of pump may be used as long as it does not depend on the exhaust speed, and there is no trouble of selecting a pump for each exhaust location.
If the pump of the type described above is further reduced in cost and commercialized, its popularity will be significant, and it is easily expected to greatly contribute to industrial development.

International Publication WO2011 / 148797 International Publication WO2012 / 004181 JP 2004-263629 A

In the above type of pump, if the screw rotor can be rotated as fast as possible, a high pumping speed can be realized while miniaturizing the pump.
However, for example, when the screw rotor is rotated at a high rotational speed exceeding several thousand rpm to 10,000 rpm, the heat generated by the drive motor and the bearing built into the pump due to the rotational speed increases, and the pump internal However, it is not easy to efficiently release this heat to the outside of the pump. Therefore, if there is no idea to efficiently and quickly release this heat to the outside of the pump, a dimensional error due to thermal expansion due to a rise in the temperature in the pump will occur in the precision component, and depending on the degree of the error, the pump exhaust performance may be reduced. If it is lowered, it may cause damage to the screw rotor. In addition, the lip seal as a shaft seal device for preventing the lubricant oil supplied to the screw rotor bearing and the steam from entering the working chamber side deteriorates early due to heat generated by the drive motor, bearing, etc. Sometimes it is.

One example of a solution to this problem is described in Patent Document 1, for example. FIG. 1A is an explanatory view conceptually showing a lubricating oil circulation path of a screw vacuum (exhaust) pump described in Patent Document 1 (corresponding to FIG. 2 of Patent Document 1). The pump shown in FIG. 1 is provided with an oil supply means 1180. The oil supply means 1180 includes an oil storage unit 1181 that stores lubricating oil, a push-up head 1182 that pushes the lubricating oil upward from the oil storage unit 1181 by centrifugal force and a drag effect, and the lubricating oil pushed up by the push-up head 1182. It comprises an oil flow passage 1183 that supplies pump components. The oil reservoir 1181 is a space that is formed below the stator 1130 and stores lubricating oil. In the oil reservoir 1181, a cooling pipe 1191 of the cooling device 1190 is disposed. As shown in FIG. 1A, the push-up head 1182 has a through-hole penetrating in the vertical direction, and the inner peripheral surface of the through-hole is formed in a tapered shape that increases in diameter from below to above. The push-up head 1182 is fixed to the lower ends of the rotary shafts 1150A and 1150B, and is configured to rotate together with the rotary shafts 1150A and 1150B when the screw vacuum pump 1100 is driven. The lubricating oil is pushed up along the tapered inner peripheral surface and the inner wall surfaces of the rotary shafts 1150A and 1150B from the oil reservoir 1181 by the centrifugal force and the drag effect using the rotation of the rotary shafts 1150A and 1150B. The oil flow passage 1183 is formed at a position physically separated from the gas working chamber described above, and supplies the lubricating oil pushed up by the push-up head 1182 to each constituent member, and the lubricating oil supplied to each constituent member. This is a circulation path that returns to the oil reservoir 1181 again. The lubricating oil flows along the inner wall that defines the oil circulation passage 1183 and also flows in the hollow oil circulation passage 1183 in the form of a mist. Specifically, as shown in FIG. 1A, the lubricating oil is pushed up from the oil reservoir 1181 by the push-up head 1182 and moves upward by centrifugal force through the hollow portions formed in the rotary shafts 1150A and 1150B. The bearings 1160Aa and 1160Ba are discharged to the outside of the rotary shafts 1150A and 1150B near the upper part.

Next, the released lubricating oil is supplied to the inside of the bearings 1160Aa and 1160Ba, and flows in a mist shape in the hollow portion formed between the bearings 1160Aa and 1160Ba and the drive motors 1140A and 1140B. It flows along the inner wall that defines the hollow portion, and is supplied into the drive motors 1140A and 1140B. Next, the lubricating oil discharged from the drive motors 1140A, 1140B flows in the form of a mist in the hollow portion formed between the drive motors 1140A, 1140B and the bearings 1160Ab, 11160Bb, and the inner wall that defines the hollow portion. And flows into the bearings 160Ab and 1160Bb. Next, the lubricating oil discharged from the bearings 1160Ab and 1160Bb flows in the form of mist in the hollow portion formed between the bearings 1160Ab and 1160Bb and the synchronous gears 1170A and 1170B, and the inner wall that defines the hollow portion. And flows to the synchronous gears 1170A and 1170B. Next, the lubricating oil supplied to the side of the synchronous gears 1170A and 1170B is supplied to the surface of the synchronous gears 1170A and 1170B including the meshing portion between the synchronous gears 1170A and 1170B. Next, the lubricating oil is supplied into the bearings 1160Ac and 1160Bc, and returned to the oil reservoir 1181 again. The cooling device 1190 cools the lubricating oil stored in the oil reservoir 1181 by a water cooling method, and as shown in FIG. 1A, a cooling pipe 1191 that is disposed in the oil reservoir 1181 and circulates the cooling water, A cooling pump 1192 for supplying cooling water to the cooling pipe 1191 is configured. In the case of the oil supply means 1180 configured as described above, sufficient lubricating oil is supplied during high-speed rotation. However, although depending on the position (release position) at which the lubricating oil is discharged to the outside of the rotating shafts 1150A and 1150B, the amount of lubricating oil discharged is extremely reduced in the low rotation speed region of about several thousand rotations or less. In some cases, sufficient cooling cannot be achieved. This phenomenon becomes more prominent as the discharge position is higher.
Therefore, by solving this phenomenon, it is possible to stably perform idling in the rotation range from low speed to high speed as well as smooth and stable operation in the high speed rotation range, and to reduce the rotation speed by adjusting the exhaust amount Making it possible to use and use in eco mode (energy saving mode) will increase the commercial value of this type of pump.

The present invention has been made by taking the creative viewpoint from a comprehensive viewpoint in view of the above points.
One of the objects of the present invention is to appropriately prevent, as desired, an increase in the temperature in the pump due to the heat generated by the rotation of the rotary shaft in the pump, the rotation of the motor, etc. An oil supply component for a screw exhaust pump capable of stably driving the pump and a screw exhaust pump provided with the component.
Another object of the present invention is to appropriately and stably supply a desired amount of oil necessary for cooling in the entire rotational speed range from the low speed range to the high speed range without depending on the lubricating oil discharge position of the rotary shaft. An oil supply component for a screw exhaust pump that can perform the above and a screw exhaust pump including the component.
Still another object of the present invention is to provide an oil supply component for a screw exhaust pump capable of efficiently releasing heat generated in the pump to the outside of the pump when the pump is operated from low speed to high speed, and the component. It is to provide a screw exhaust pump.
Yet another object of the present invention is to achieve ultra-high speed operation, even if a relatively long rotating shaft is provided with a lubricating oil discharge port at a high position, continuous operation at a relatively low speed for a long time. An object is to provide an oil supply component for a screw exhaust pump and a screw exhaust pump including the component.

A first aspect of the present invention includes a rotor having at least one screw groove on the outside and having a hollow portion opened at a lower end surface in the rotation axis direction, and a gas intake port and an exhaust port, and houses the rotor. A stator, a rotating shaft that is connected to or formed as a part of the rotor, and at least a part of which is accommodated in the hollow part, and is accommodated in the hollow part and rotatably supports the rotating shaft. Bearings, and
The rotating shaft has a first oil supply passage that extends in the longitudinal direction and opens in a lower end portion and a hollow portion, and the oil supply passage is a second oil supply passage that opens on the outer surface of the rotating shaft. An oil supply component for a screw exhaust pump that communicates with the road,
The rotating shaft and a helical structure capable of exhibiting a pumping function in the rotating shaft,
The structure is composed of a drivable spiral structure positioned below the rotating shaft and a fixed spiral structure positioned above the rotatable shaft, and an oil supply component for a screw exhaust pump, There is a screw exhaust pump with its parts.

The second aspect of the present invention has a male rotor and a female rotor having screw teeth that mesh with each other,
A stator having a gas inlet and an outlet and accommodating the male and female rotors;
At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion;
A bearing housed in the hollow portion and rotatably supporting the rotating shaft;
The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end portion and a hollow portion,
An oil reservoir disposed below the stator, storing oil to be supplied to an oil supply path of the rotating shaft, and collecting oil supplied into the hollow portion through the oil supply path;
At least a portion is disposed between the rotating shaft and an inner wall surface of the at least one rotor that defines the hollow portion, and is fixed to the stator and supplied to the hollow portion through the oil supply path. An oil supply component for a screw exhaust pump, having a flow path member that defines a plurality of oil flow paths for distributing and flowing oil into a plurality of flow paths in the hollow portion,
The rotating shaft has a helical structure capable of exhibiting a pumping function in the rotating shaft, and the structure has a drivable helical structure located below the rotating shaft and an upper side thereof. An oil supply component for a screw exhaust pump and a screw exhaust pump having the component are characterized by comprising a fixed helical structure positioned.

A third aspect of the present invention has a male rotor and a female rotor having screw teeth that mesh with each other,
A stator having a gas inlet and an outlet and accommodating the male and female rotors;
At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion;
A bearing housed in the hollow portion and rotatably supporting the rotating shaft;
The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end portion and a hollow portion,
An oil supply component for a screw exhaust pump having an oil amount adjusting mechanism that is provided for the bearing and adjusts the supply amount of oil supplied to the bearing through the oil supply path,
The rotating shaft has a helical structure capable of exhibiting a pumping function in the rotating shaft, and the structure has a drivable helical structure located below the rotating shaft and an upper side thereof. An oil supply component for a screw exhaust pump and a screw exhaust pump having the component are characterized by comprising a fixed helical structure positioned.

A fourth aspect of the present invention has a male rotor and a female rotor having screw teeth that mesh with each other with a predetermined gap,
A stator having a gas inlet and an outlet and accommodating the male and female rotors;
At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion;
The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end portion and a hollow portion,
A motor rotor fixed to the rotating shaft; and a motor stator disposed around the motor rotor; and at least a part of the hollow portion being disposed and a driving motor integrally provided on the rotating shaft. ,
A screw exhaust pump having a guide member for guiding oil supplied through an oil supply path of the rotating shaft that rotates to a gap between a motor rotor and a motor stator of the drive motor and an outer peripheral surface of the motor stator. Oil supply parts,
The rotating shaft has a helical structure capable of exhibiting a pumping function in the rotating shaft, and the structure has a drivable helical structure located below the rotating shaft and an upper side thereof. An oil supply component for a screw exhaust pump and a screw exhaust pump having the component are characterized by comprising a fixed helical structure positioned.

A fifth aspect of the present invention has a male rotor and a female rotor having screw teeth that mesh with each other,
A stator having a gas inlet and an outlet and accommodating the male and female rotors;
At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion and rotatably supported;
The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end surface and a hollow portion,
The oil is disposed below the stator and stores oil to be supplied through an oil supply path of the rotary shaft, and collects oil supplied into the hollow portion through the oil supply path of the rotary shaft. And
A partition that defines a closed space for filling the oil;
A change element that defines a part of the closed space and is capable of changing a volume of the closed space;
An oil outlet that communicates with the oil supply path of the rotating shaft;
An oil inlet into which oil recovered after being supplied into the hollow portion through the exhaust port of the rotating shaft;
A pressure mechanism for operating the change element to pressurize the oil in the closed space in order to push up the oil filled in the closed space toward the oil supply path of the rotary shaft through the oil outlet. An oil supply part for a screw exhaust pump having an oil reservoir,
The rotating shaft has a helical structure capable of exhibiting a pumping function in the rotating shaft, and the structure has a drivable helical structure located below the rotating shaft and an upper side thereof. An oil supply component for a screw exhaust pump and a screw exhaust pump having the component are characterized by comprising a fixed helical structure positioned.

ADVANTAGE OF THE INVENTION According to this invention, the rise in the temperature in a pump resulting from the heat | fever which generate | occur | produces with rotation of the rotating shaft in a pump, rotation of a motor, etc. can be blocked | prevented suitably as desired, and it can stabilize stably from a low speed area to a high speed area. An oil supply component for a screw exhaust pump that can be driven by a pump and a screw exhaust pump including the component can be provided.
Furthermore, according to the present invention, it is possible to appropriately and stably supply a desired amount of oil necessary for cooling in the entire rotational speed range from the low speed range to the high speed range without depending on the lubricating oil discharge position of the rotary shaft. An oil supply component for a screw exhaust pump and a screw exhaust pump including the component can be provided.
Furthermore, according to the present invention, there is provided an oil supply component for a screw exhaust pump and its component capable of efficiently releasing heat generated in the pump to the outside of the pump as the pump is operated from low speed to high speed. A screw exhaust pump provided can be provided.
In addition, according to the present invention, even with a relatively long rotating shaft, even if a lubricating oil discharge port is provided at a high position, continuous operation for a long time can be performed at a relatively low speed while realizing ultra high speed operation. An oil supply component for a screw exhaust pump and a screw exhaust pump including the component can be provided.

Typical sectional drawing for demonstrating the screw exhaust pump of a prior art example. FIG. 6 is a schematic cross-sectional view for explaining a specific example of a push-up head. The typical explanatory view for explaining the principal part of the 1st experimental device concerning the present invention. The typical explanatory view for explaining the principal part of the 2nd experimental device concerning the present invention. The graph which shows an example of an experimental result. The typical partial cross section perspective view for demonstrating the internal structure of the oil supply component 5000. FIG. FIG. 6 is a schematic enlarged view of the vicinity of a drive screw 5005 and a fixed screw 5006a in FIG. The typical perspective view which shows one of the suitable examples of the fixing screw used for the components of this invention. The typical perspective view which shows a suitable example of the drive screw used for the components of this invention. The typical perspective view which shows the other suitable example of the drive screw used for the components of this invention. 1 is a schematic cross-sectional view of a gas exhaust pump according to an embodiment of the present invention. The schematic diagram which shows a suitable example of the connection position of the male rotor which concerns on one Embodiment of this invention, and a rotating shaft. The schematic diagram which shows another example of the connection position of the rotor which concerns on one Embodiment of this invention, and a rotating shaft. The schematic diagram which shows the primary resonance which generate | occur | produces in the rotor of FIG. The typical external appearance perspective view seen from the upper end side of the male rotor of the gas exhaust pump of FIG. The typical external appearance perspective view seen from the lower end side of the male rotor of the gas exhaust pump of FIG. The typical sectional view for explaining the access method to the mass attachment part. The typical sectional view showing the structure around a shaft seal device and a bearing. The typical perspective view which shows the structure of an oil amount adjustment ring. The schematic top view of a support member. The typical sectional view of a support member. The typical external appearance perspective view of a motor stator. The typical sectional view showing the oil circulation course of an oil circulation system. The typical sectional view showing other embodiments of an oil circulation system. The schematic diagram which shows an example of the cooling path | route of the oil in the oil tank of FIG. FIG. 6 is a schematic cross-sectional view showing still another embodiment of the oil circulation system.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially the same function structure, duplication description may be abbreviate | omitted by attaching | subjecting the same code | symbol.

"Experiment"
(1) Outline of Experimental Apparatus FIG. 2 is a schematic explanatory diagram for explaining the main part of the first experimental apparatus (comparative example apparatus) according to the present invention.
The oil supply apparatus 2000 includes a transparent glass tube 2001, an oil reservoir 2002, and a rotation drive device (not shown) for rotating the glass tube 2001 as main components.
The hollow part of the glass tube 2001 constitutes an oil flow passage 2001a.
The glass tube 2001 corresponds to the rotary shaft of the pump, and a transparent one is selected to facilitate observation of the behavior of the internal oil (in the experiment, trade name: Pyrex (registered trademark) is used). A hollow push-up head 2003 having a tapered inner surface is provided in the lower end portion of the glass tube 2001. An oil inflow port 2007 is provided at the lower end of the push-up head 2003.
An outflow portion 2004 is provided in the upper part of the glass tube 2001, and a flow path 2004a is formed therein.
On the glass tube 2001 side of the flow path 2004a, an outlet 2005 is provided for oil in the glass tube 2001 to flow out of the glass tube 2001. On the opposite side, a discharge port (open end) 2006 for discharging oil to the outside is provided.
In the experiment, a predetermined amount of oil 2008 is put into the oil reservoir 2002.
The inner diameter of the glass tube 2001 used for the experiment was 15 mm, and the height difference from the oil liquid level 2009 to the central axis along the discharge direction of the outflow portion 2004 was 37 cm. The diameter of the channel 2004a was 9 mm. The rotation speed of the glass tube 2001 was made to be able to rotate up to 8000 rpm.
FIG. 3 is a schematic explanatory view for explaining a main part of a second experimental apparatus (invention example apparatus) according to the present invention having the main configuration of the present invention.
The oil supply device 3000 includes a transparent glass tube 2001, an oil reservoir 2002, and a rotation drive device (not shown) for rotating the glass tube 2001 as main components as in FIG.
Inside the glass tube 2001, a shaft rod 3001 is disposed at the central axis position of the glass tube 2001. The shaft rod 3001 has an upper end fixed to the bearing 3002 and a shaft rod rotation stop 3003 at the lower end.
The bearing 3002 has a function of preventing the rotational shake of the crow pipe 2001 at the same time as fixing the shaft rod 2001. Therefore, the outer surface of the bearing 3002 is smoothed so that it can slide or substantially slide along the inner wall surface of the crow pipe 2001, and its outer diameter is also determined to maintain smoothness. It has been.
Four fixed screws, a fixed screw A 3004a, a fixed screw A 3004b, a fixed screw A 3004c, and a fixed screw A 3004d, are fixed to a predetermined position of the shaft rod 3001 in this order from below.
The outer diameter of each fixed screw is determined so that the inner wall surface of the glass tube 2001 can slide or substantially slide when the glass tube 2001 rotates.
A driving screw 3005 is provided at the lower end of the fixed screw A3004a so that the lower end position thereof coincides or substantially coincides with the lower end position of the glass tube 2001.
The drive screw 3005 is fitted to the glass tube 2001 as shown in the figure so that it can be rotated with the rotation of the glass tube 2001, and the rotational force of the glass tube 2001 is directly transmitted. The glass tube 2001 is rotatably attached so that the transmission of the rotational force of the glass tube 2001 is not hindered.
In the experiment, the glass tube 2001 and the outflow portion 2004 were the same as those in FIG. The oil level 2009 was the boundary position between the lower end of the fixed screw A3004a and the upper end of the drive screw 3005.
Each fixing screw has the same structure as shown in FIG. 19, and the driving screw 3005 has the same structure as shown in FIG. 20A.
The width (thickness) in the central axis direction of each fixed screw used in the experiment was 10 mm, and the direction of twist was equal inclination opposite to that of the drive screw 3005.
A drive screw 3005 having an equal inclination was used. The width (thickness) of the drive screw 3005 in the central axis direction was 25 mm.
The inclination pitch of each fixed screw and drive screw 3005 was the same.
The fixed screw A3004a, fixed screw A3004b, and fixed screw A3004c were fixed to the shaft 3001 so as to be stacked in order from the upper end position of the drive screw 3005 as shown in FIG.
The fixing screw A3004d was fixed to the shaft rod 3001 so that the lower end position thereof was 20 cm from the oil level 209.

(2) Experimental procedure / conditions and experimental system Using the apparatus shown in Figs.

*: Pump capacity of externally used pump ... 1400cc / min
*: Observation of oil movement in the glass tube is visual and video shooting.
*: Oil discharge measurement ·····································································
*: Number of rotations of glass tube: 6 points of 1000, 2000, 3000, 4000, 6000, 7200 rpm

"Experimental system"
(1) Single glass tube with the structure of Fig. 2
(2) Combination of glass tube and external pump with the structure of Fig. 2
(3) External pump alone
(4) Glass tube with the structure of Fig. 3 alone

The experimental results are shown in FIG.
The following points were found in this experiment.
(A) In the case of the experimental system (2), in the experimental system (1), an oil supply shortage has occurred so far at ultra-high speed rotation (6500 rpm or more). The shortage of supply was compensated (the effect was observed at 4000 rpm or higher, and the effect became large as the rotational speed increased). However, in the low speed range (4000 rpm or lower), the glass having the structure of FIG. This is the first time that the oil supply is extremely short compared with the experimental system (3) with an external pump alone, which is not much different from the experimental system with a single pipe (1).
(B) In the experimental system (3) with an external pump alone, when oil was supplied into the glass tube without rotating the glass tube, almost no oil was discharged from the discharge port. Therefore, in order to avoid the influence of the experimental system (1), the experiment was performed by setting the position of the inflow port 2007 above the oil liquid level 2009.
In this case, although the oil supply is sufficient from around the low speed rotation range (2000 rpm), it has been found that when the rotational speed exceeds about 4000 rpm, the discharge amount tends to be saturated.
(C) In the experimental system (4) having only the glass tube having the structure of FIG. 3 according to the present invention, as can be seen from the graph, the oil supply force is about ½ of the experimental system (3) even at 2000 to 3000 rpm. It was found that at 4000 rpm or higher, the oil supply force is four times or more that of the experimental system (1) with a glass tube having the structure shown in FIG.
It was also found that around 5000 rpm, the oil supply force was reversed with the experimental system (3) of the external pump alone, and in the higher rotation speed range, the difference widened as the rotation speed increased.

First Embodiment FIG. 5 shows one representative example of a preferred embodiment of an oil supply component for a screw exhaust pump according to the present invention.
FIG. 5 is a schematic partial cross-sectional perspective view for explaining the internal structure of the oil supply component 5000.
The oil supply component 5000 has a shaft bar 5002 disposed in the rotation shaft 5001 (oil flow passage 5008) disposed in the rotor of the pump so that its axis coincides with the central axis. A shaft bar 5002 is supported at its upper end by a bearing 52003 slidably disposed on the inner wall surface of the rotating shaft 5001, and the other end is used to stop the rotation of the shaft bar 5002. Is provided.
A drive screw 5005 is slidably and rotatably attached to the shaft rod 5002, and four fixed screws 5006a, 5006b, 5006c, and 5006d are fixed above the shaft rod 5002 at a predetermined interval according to the design.
Outflow passages 5007a, 5007b, 5007c, and 5007d for discharging the supplied oil to the outside are provided in the vicinity of the upper end portion of the rotating shaft 5001 and the lower end portion of the bearing 5003.
FIG. 5 shows an example in which two outflow passages 5007 are provided above the rotating shaft 5001 and two near the upper end of the fixing screw 5006c, for a total of four. There is no limitation, and the flow path inner diameter, number, and position are determined according to the design so that a desired oil supply can be performed.
The spiral direction of the drive screw 5005 is opposite to the spiral direction of the four fixed screws 5006a, 5006b, 5006c, and 5006d. In the case of FIG. 5, the spiral direction of the drive screw 5005 is counterclockwise as viewed from above.
5 shows an example in which the four fixed screws 5006a, 5006b, 5006c, and 5006d are provided at substantially equal intervals. In the present invention, the number of fixed screws and the arrangement interval are limited to this example. Rather, it is determined according to the design of the pump so as to obtain the desired oil supply capacity.
For example, a plurality of fixed screws may be arranged by sequentially reducing the arrangement interval from the bottom at a predetermined interval, or the spiral winding condition may be varied between the plurality of fixed screws. Or it is good also as one long fixed screw from the upper end of the drive screw 5005 to the lower end vicinity of the outflow part 5007a of the rotation shaft 5001, 5007b.
A schematic enlarged view of the vicinity of the drive screw 5005 and the fixed screw 5006a in FIG. 5 is shown in FIG.

The outer surface of the drive screw 5005 (the outer end surface of the spiral portion) is firmly fitted or the like so that it can be reliably driven without sliding along the inner wall surface 6001 when the inner wall surface 6001 of the rotating shaft 5001 rotates. It is fixed.
The drive screw 5005 is rotatable about the shaft rod 5002.
Unlike the drive screw 5005, the fixed screw 5006 a is fixed to the shaft 5002, but is disposed with a slight gap between the fixed screw 5006 a and the inner wall surface 6001 so as not to respond to the rotation of the inner wall surface 6001. ing.
In FIG. 6, when the rotary shaft 5001 rotates clockwise as viewed from above, the drive screw rotates integrally with the rotary shaft 5001, sucks oil, and feeds it in the direction of the fixed screw 5006a. The oil fed in the direction of the fixed screw 5006a rises while turning along the inner wall 6001 of the rotating shaft 5001 from the lower end of the fixed screw 5006a toward the upper end.
The oil that has passed the upper end of the fixed screw 5006a continues to rise while turning along the inner wall 6001, and reaches the lower end of the fixed screw 5000b.
The arrangement interval between the fixed screw 5006a and the fixed screw 5000b is considered so that the oil layer thickness rising along the wall surface 6001 between the fixed screw 5006a and the fixed screw 5000b becomes thin and the supply amount does not become less than desired. It is decided appropriately.
This is the same between the fixed screw 5006b and the fixed screw 5000c and between the fixed screw 5000c and the fixed screw 5000d.

FIG. 7 is a schematic perspective view showing one preferred example of the fixing screw used in the component of the present invention.
The fixing screw 7000 shown in FIG. 7 has a spiral direction that is the rotational direction of the hands of the watch as viewed from above. By making the spiral a gentler ascending spiral shape, the oil can be transported more reliably.
FIGS. 8A and 8B are schematic perspective views showing one preferred example of the drive screw used for the component of the present invention.
8A and 8B, the spiral directions of the drive screws 8000A and 8000B are opposite to the rotation direction of the watch hands as viewed from above.
The drive screw 8000A shown in FIG. 8A shows a case where the spiral has an equal inclination, and the drive screw 8000B shown in FIG. 8B shows a case where the spiral has an unequal inclination.

Next, a first embodiment of the screw exhaust (vacuum) pump according to the present invention will be described with reference to FIGS.
First, the basic configuration of the screw vacuum pump will be described. As shown in FIG. 9, the screw vacuum pump 100 includes a pair of male rotors 110 and female rotors 120 that are arranged in mesh with each other while maintaining a meshing gap and rotate in the reverse direction, A stator 130 for housing the female rotor 120, rotary shafts 150A and 150B connected to the male and female rotors 110 and 120, a drive motor 140 provided integrally with the rotary shaft 150A, and the rotary shaft 150A are rotatable. Bearing bearings 160, 161, 162 for supporting, a pair of synchronous gears 170A, 170B attached to the lower ends of the rotary shafts 150A, 150B, an oil reservoir 300 provided below the stator 130 and containing oil OL, The oil supply component 5000 and the oil reservoir 30 described above Comprising a cooling device 190 the contained oil OL is cooled by water-cooled, and the shaft seal device 230 disposed above the bearing 160, a support member 200 for supporting the shaft sealing device 230, to.
In FIG. 9, the details of the structure in the female rotor 120 are omitted, but a bearing is provided on the female rotor 120 side as well as the male rotor 110, and the rotary shaft 150B is rotatably supported. The same shaft seal device and support member as those on the male rotor 110 side are provided, but no drive motor is provided. Note that the present invention is not limited to this, and a drive motor may be integrally provided on the rotating shaft 150B on the female rotor side (in this case, for example, it is rotated so as to be synchronized using an inverter). It is also possible to make the configuration of the female rotor side shaft sealing device, the support member, etc. different from that of the male rotor 110 side.

The stator 130 is made of a metal such as stainless steel, and as shown in FIG. 9, a main body 131 that houses the male rotor 110 and the female rotor 120, and a lower end of the main body 131, and an exhaust port 136. The formed base portion 132, an end plate 133 that covers the upper end side of the main body portion 131, and an intake port portion 134 that is fixed to the end plate 133 and defines the intake port 135.

The stator 130, the male rotor 110, and the female rotor 120 cooperate to form a gas working chamber that transfers and compresses gas. The male rotor 110 and the female rotor 120 respectively have screw teeth 111 and 121 that mesh with each other while maintaining a meshing gap. The screw teeth 111 and 121 of the male rotor 110 and the female rotor 120 are disposed on the intake port 135 side, and are unequal lead unequal inclination angle screw portions (hereinafter referred to as unequal lead screw portions) 111a for transporting and compressing gas. , 121a and unequal lead screw portions 111a, 121a, and equal lead screw portions 111b, 121b for transferring gas. The equal lead screw portions 111b and 121b are formed with equal lead equal inclination angles and have straight tooth traces. The unequal lead screw portions 111a and 121a are formed such that the lead and the inclination angle (lead angle) gradually decrease from the intake port 135 side to the exhaust port 136 side, and have curved tooth traces. . In the unequal lead screw portions 111 a and 121 a, the lead angle changes according to the rotation angles of the male rotor 110 and the female rotor 120, and between one lead of the gas working chamber formed by the male rotor 110 and the female rotor 120 and the stator 130. Is continuously reduced from the intake port 135 side toward the exhaust port 136 side, whereby gas transfer compression is performed.

The rotary shaft 150A is formed of a metal such as stainless steel, and the upper end side is rotatably supported by the support member 200 via the bearing 160 and is coaxially connected to the male rotor 110. The structure of the support member 200 will be described later. Bearings 161 and 162 are provided on the lower end side of the rotating shaft 150 </ b> A. The bearing 161 is held by a first bearing holder 137 and the bearing 162 is held by a second bearing holder 138. The first bearing holder 137 is fixed to the lower end portion of the support member 200, and the second bearing holder 138 is fixed to the base portion 132.

The bearing 160 is an angular ball bearing and supports most of the loads of the male rotor 110 and the rotating shaft 150A. Although the bearings 161 and 162 are also angular ball bearings, these are mainly provided to suppress the swing of the rotating shaft 150 </ b> A that may occur during the high-speed rotation of the male rotor 110. The lubrication of the bearings 160 to 162 will be described later.

The drive motor 140 includes a motor rotor 141 fixed between the bearings 160 and 161 of the rotary shaft 150A, and a stator 142 disposed around the motor rotor 141 and fixed to the support member 220 so that a predetermined gap 143 is formed. It is driven by receiving AC power from the outside of the pump.

Vibration Suppression Structure Here, a structure for suppressing vibration generated when the male and female rotors rotate at high speed will be described. FIG. 11 is a schematic diagram showing the relationship between a conventional male rotor and a rotating shaft. The rotor 510 shown in FIG. 11 is the same as the male rotor 110 with respect to the screw teeth on the outer peripheral side, but a hollow 512 is formed at the upper end 510t with a connecting portion 512 to the rotary shaft 550 and opens at the lower end surface in the rotation axis direction. A hollow portion 511 accommodates a part 511 and a bearing 560 that rotatably supports a part of the rotation shaft 550 and the rotation shaft 550.

It was found that when the rotor 510 was rotated at a high speed, a primary resonance point was present in the vicinity of 7000 rpm, and vibration as shown in FIG. 4 occurred. This vibration deformation mode is an axial bending deformation with the bearing 560 as a restraint portion as a base point.

In the present invention, the structure shown in FIG. 10 is adopted in order to increase the resonance frequency of the rotor. As shown in FIG. 2, the male rotor 110 has a lower hollow portion 113A that opens at the lower end surface 110b in the direction of the rotation axis AX, and an upper hollow portion 113B that opens at the upper end surface 110t. The hollow portion 113B communicates with the hollow portion 113B through a through hole 112h formed in the connecting portion 112. The connecting portion 112 is connected to a flange portion 151 formed at the upper end portion of the rotating shaft. The connecting portion 112 is disposed at a position away from the upper end surface 110 t and the lower end surface 110 b of the male rotor 110, and the rotation axis AX direction of the connecting portion 112 is located near the center of gravity GC of the male rotor 110. In this way, the connection position between the rotary shaft 150 and the male rotor 110 is moved to the position of the center of gravity GC of the male rotor 110, and the distance between the bearing 160 serving as the restraint portion and the connection portion between the rotary shaft 150 and the male rotor 110 is set. It was found that the resonance frequency of the male rotor 110 can be increased by shortening the length compared to the conventional one. Specifically, the primary resonance point of the male rotor 110 could be increased to over 10,000 rpm. Further, by connecting the rotating shaft 150 and the male rotor 110 to the inside of the male rotor 110, the entire length of the rotating shaft 150 can be shortened as compared with the conventional one, and weight reduction, vibration suppression, and the like can be achieved. But it is advantageous. Although only the male rotor 110 has been described, the same structure is adopted for the female rotor 120.

Balance Adjustment Mechanism Next, the balance adjustment mechanism of the screw vacuum pump according to the present embodiment will be described. As shown in FIG. 13A, a plurality of end surface portions 114 formed at the end of the unequal lead screw portion 111 a on the upper end side of the male rotor 110 are used as masses for adjusting the rotational balance of the male rotor 110. A plurality of mass attaching portions 114h for attaching the screw M are arranged. The mass attaching part 114h is configured by, for example, a screw hole. The end surface portions 114 are arranged at equal intervals in the circumferential direction around the rotation axis AX, and are orthogonal to the rotation axis AX. The plurality of mass attaching portions 114h are arranged along the circumferential direction, and are also arranged at equal intervals in the radial direction. As shown in FIG. 13B, a disk-shaped plate 115 is formed integrally with the male rotor 110 at the lower end of the male rotor 110. The center of the disk-shaped plate 115 coincides with the rotation axis AX, and the outer peripheral surface 115f of the disk-shaped plate 115 is parallel to the rotation axis AX. A plurality of mass attaching portions 115h are formed on the outer peripheral surface 115f at regular intervals along the circumferential direction. The mass attachment portion 115h is configured by, for example, a screw hole formed toward the center of the disk-shaped plate 115. A screw M as a mass for adjusting the rotational balance of the male rotor 110 can be attached to the mass attaching portion 115h.

Of course, it is possible to adjust the rotational balance of the male rotor 110 by selectively attaching the screws M to the mass attaching portion 114h and the mass attaching portion 115h. After the assembly, the mass attaching portion 114h and the mass attaching portion 115h are accessible. Even if each component involved in the rotation is balanced, after the screw vacuum pump 100 is assembled, the rotating system is not always balanced, and the rotation balance may be further adjusted. Therefore, in the present invention, as shown in FIG. 14, a passage 132 a is formed in the base portion 132 of the stator 130 to allow access to the mass attaching portion 115 h from the outside of the stator 130. The passage 132a is normally sealed and opened only when necessary. The mass attaching portion 114h on the upper end side of the male rotor 110 is accessible from the outside of the stator 130 through the air inlet 135, as shown in FIG. In the present embodiment, the mass attaching portions are provided at the upper and lower ends of the male rotor 110. However, the present invention is not limited to this. For example, the mass attaching portions are formed in the intermediate portion in the rotation axis direction of the male rotor 110. It is also possible. Although only the male rotor 110 has been described, the same structure is adopted for the female rotor 120.

Oil Circulation System Next, the oil circulation system will be described. Only the oil circulation system on the male rotor 110 side will be described, but the same structure can be adopted on the female rotor 120 side. As shown in FIG. 9, the rotary shaft 150 </ b> A has an oil supply path 152 formed by a through hole extending in the longitudinal direction at the center thereof. The opening at the lower end surface of the through hole formed in the rotating shaft 150A is an inlet 153 into which the oil OL flows, and the opening at the upper end surface of the through hole is a plug fixed to the connecting portion 112 of the male rotor 110. It is sealed with a member 156. Here, as shown in an enlarged view in FIG. 15, the oil supply path 152 communicates with an oil supply path 152 a extending in the radial direction of the rotating shaft 150 </ b> A formed above the bearing 160, and the outer periphery of the rotating shaft 150 </ b> A. The end of the oil supply path 152a that opens at the surface is an outlet 154 from which the oil OL flows out. The oil supply path 152a is formed at two positions symmetrical with respect to the rotation axis AX, and each oil supply path 152a has a flow path 155h having a flow path area defined so as to adjust the flow rate of the oil OL to a predetermined amount. The flow rate adjusting member 155 formed with is screwed.

Referring back to FIG. 9, an oil supply component 5000 that pushes up the oil OL from the oil reservoir 300 is provided in the rotary shaft 150A. The oil OL pushed up through the inflow port 153 moves upward along the inner wall of the oil supply path 152, and is discharged from the outflow port 154 to the outside of the rotary shaft 150A through the oil supply path 152a and the flow rate adjusting member 155. .

Oil Quantity Adjusting Mechanism Returning to FIG. 15, an annular oil quantity adjusting ring 220 is provided between the bearing 160 of the rotating shaft 150 </ b> A and the outlet 154. The oil amount adjusting ring 220 is fixed to the rotating shaft 150A. As shown in FIG. 16, the oil amount adjusting ring 220 includes an annular lower plate portion 221, an annular upper plate portion 222 facing the lower plate portion 221, and a lower plate portion 221 and an upper plate portion 222 on the inner peripheral side. And a connecting wall portion 223 to be connected. The connecting wall 223 is formed with a flow hole 225 formed at a position corresponding to the outlet 154 of the oil supply passage 152a extending in the radial direction of the rotary shaft 150A. A plurality of oil supply holes 226 that supply oil OL for lubricating the bearing 160 are arranged in the lower plate portion 221 at equal intervals along the circumferential direction. On the upper part of the outer periphery of the lower plate part 221, a flange part 24 is formed. The flange 24 serves to prevent the oil OL from falling downward from between a receiving plate 210 (described later) fitted into the outer peripheral surface 228 of the lower plate 221 and the lower plate 221.

Here, the reason why the oil amount adjustment ring 220 is provided will be described. It is necessary to supply oil OL for lubrication during high-speed rotation to the bearing 160 that rotatably supports the loads of the male rotor 110 and the rotating shaft 150A. If this supply amount is excessive, the bearing 160 It has been found that the heat generated increases. For this reason, in the present invention, the oil amount adjusting ring 220 is provided above the bearing 160 to optimize the supply amount of the oil OL. The number and dimensions of the oil supply holes 226 of the oil amount adjustment ring 220 are adjusted in advance so that the supply amount of the oil OL is optimized. Note that when fine adjustment of the supply amount of the oil OL is necessary, for example, the necessary number of oil supply holes 226 are left and the unnecessary oil supply holes 226 are closed with a metal plate or the like. The oil amount adjusting ring 220 is not limited to the oil amount adjusting mechanism of the present invention. Further, although the oil amount adjusting ring 220 is fixed to the rotating shaft 150A, an oil amount adjusting mechanism can be realized without being fixed to the rotating shaft 150A.

15, the receiving plate 210 is formed in an annular shape, covers the upper part of the bearing 160 together with the oil amount adjusting ring 220, and is fixed to the support member 200. The receiving plate 210 is provided to guide oil OL discharged from the outlet 154 of the rotary shaft 150A to a plurality of inlets 201a and 202a formed in the support member 200 described later. A circulation hole 210h is formed at a position corresponding to 201a and 202a.

The support member 200 is formed of a metal such as stainless steel and is formed in a cylindrical shape as shown in FIGS. 9A and 9B. As shown in FIG. 1, the support member 200 is formed in the cylindrical hollow portion 113A of the male rotor 110. A slight gap is formed between the outer peripheral surface 206 of the support member 200 and the inner wall surface of the hollow portion 113A. The support member 200 has a lower end fixed to the base portion 132 of the stator 130, and extends in the direction of the rotation axis AX so as to reach the middle of the unequal lead screw portion 111a from the base portion 132 through the opening of the hollow portion 113A. It is extended. With such an arrangement, the support member 200 is transmitted with heat from the male rotor 110 that becomes high temperature due to the compression heat of the gas. In particular, the male rotor 110 is expected to have the highest temperature at the end portion of the unequal lead screw portion 111a on the side of the equal lead screw portion 111b. However, by disposing the support member 200 in the vicinity thereof, the heat of the male rotor 110 is increased. Can be received effectively. Further, since the support member 200 holds the bearing 160 in the bearing holding portion 203, the heat generated by the bearing 160 can be effectively received. A plurality of first flow paths 201 and a plurality of second flow paths 202 are formed on the outer peripheral side of the bearing holding portion 203 through which oil OL extending in the vertical direction flows. The first flow path 201 is formed so as to distribute the oil OL flowing from the inflow port 201 a to the gap 143 formed between the motor rotor 141 and the motor stator 142 of the drive motor 140. The second flow path 202 is formed so as to distribute the oil OL flowing from the inlet 202 a onto the outer peripheral surface 142 a of the motor stator 142. That is, the support member 200 also serves as the flow path member and the guide member of the present invention. Note that the present invention is not limited to this, and the flow path member and the guide member may be separate members.

As shown in FIG. 18, the motor stator 142 has a plurality of grooves 142b formed on the outer peripheral surface 142a and extending in the rotation axis direction. The groove 142b cooperates with the inner wall surface 205 of the support member 200 to form a flow path for circulating the oil OL supplied from the second flow path 202.

As shown in FIG. 9, the oil reservoir 300 is formed at a lower portion of the stator 130 and is provided for storing the oil OL. In the oil reservoir 300, a cooling pipe 191 of the cooling device 190 is disposed. The cooling device 190 cools the oil OL stored in the oil reservoir 300 by a water cooling method, and is disposed in the oil reservoir 300 and circulates the cooling water, and supplies the cooling water to the cooling pipe 191. A cooling pump 192 is included.

The shaft seal device 230 prevents the oil OL and its vapor supplied from the outlet 154 of the rotary shaft 150A from entering the gas working chamber formed by the stator 130, the male rotor 110, and the female rotor 120 in cooperation. The rotary shaft 150A is sealed. As shown in FIG. 7, the shaft seal device 230 is formed in an annular shape and fixed to the upper end of the support member 200, and a first seal that holds the first lip seal 233a and the second lip seal 233b. The assembly 232 includes a second seal assembly 234 disposed adjacent to the first seal assembly 232 and holding the lip seal 234a, and a labyrinth seal 235 provided adjacent to the second seal assembly 234. The first and second lip seals 233a, 233b and the lip seal 234a that are in contact with the surface of the rotating shaft 150A are characterized by having heat resistance, chemical stability, low friction properties, and moderate elasticity. It is desirable to be composed of a fluorinated resin.
Examples of such fluorinated resins include (1) perfluorinated resins, such as polytetrafluoroethylene (PTFE), (2) partially fluorinated resins, such as polychlorotrifluoroethylene (PCTFE, CTFE) Polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), etc. (3) Fluorinated resin copolymers such as perfluoroalkoxy fluororesin (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP) ), Ethylene / tetrafluoroethylene copolymer (ETFE), ethylene / chlorotrifluoroethylene copolymer (ECTFE), and the like. Of these, PFA and PTFE are particularly preferable.
Since these resins can be provided on a metal such as nickel (Ni), nickel fluoride (NiF ₂ ) and the like, the heat resistance can be drastically improved. It is preferable.

The holding member 231 is provided with a seal gas supply path 231a. A seal gas such as nitrogen gas is supplied to the seal gas supply path 231a, and the upper end side from the gas passage 232a formed in the main body of the first seal assembly 232 is provided. And flows toward the lower end side, and is discharged through a gas passage 232b formed in the main body of the first seal assembly 232. The supply path and discharge path (not shown) of the seal gas are formed in the support member 200 and the stator 130, and the seal gas is supplied from the outside of the pump through this supply path and passes through the gas passage 232b. Is discharged to the outside of the pump through a discharge path (not shown) and collected by a collection device (not shown). Here, if the rotating shaft 150A is made of stainless steel, PTFE may be thermally decomposed by the catalytic effect of stainless steel when the temperature rises to about 180 ° C. or higher. Therefore, in this embodiment, the oil circulation system efficiently releases the heat in the pump to the outside to suppress the temperature rise of the lip seal, but to prevent the lip seal from deteriorating and to obtain a stable sealing performance for a long period of time. In addition, since Ni has the highest thermal decomposition suppression effect, a nickel plating film or a nickel fluoride film may be applied to the contact portion of the rotary shaft 150A between the first and second lip seals 233a, 233b and the lip seal 234a. preferable.

Here, when the oil circulated by the oil circulation system of the present embodiment is in the air, bubbles are generated in the oil, and the cooling efficiency of the oil is lowered. Further, when the PTFE of the lip seal is exposed to oxygen gas in a state where the temperature has risen, it is easily oxidized and degraded. In order to prevent this, it is extremely important to remove dissolved oxygen in the circulating oil. For this reason, in the present embodiment, it is preferable that the space in which the oil circulates is a sealed space and the sealed space is decompressed. In order to decompress the space in which the oil circulates, for example, a vacuum formed by the screw vacuum pump 100 can be used. It is also possible to provide another pump to reduce the pressure. The pressure reduction may be, for example, a pressure at which the saturation solubility of air is about half of the saturation solubility at atmospheric pressure.

Next, the oil circulation of the above oil circulation system will be described with reference to FIG. When the screw vacuum pump 100 is driven, as shown in FIG. 11, the oil OL cooled in the oil reservoir 300 passes through the oil supply path 152, the oil supply path 152a, and the outlet 154 of the rotary shaft 150A. A part of the oil OL is supplied to the bearing 160 through the oil supply hole 226 of the lower plate part 221 for lubrication of the bearing 160, and is supplied to the bearing 160 on the lower plate part 221 and the receiving plate 210. Falls from the bearing 160 and is supplied to the gap 143 of the drive motor 140. The oil OL supplied onto the receiving plate 210 is distributed to the first and second flow paths 201 and 202. The heat generated in the bearing 160 is absorbed by the oil OL supplied directly to the bearing 160 and is absorbed by the oil OL flowing through the first and second flow paths 201 and 202 that pass around the bearing 160. . The oil OL flowing through the first and second flow paths 201 and 202 absorbs heat received from the rotary shaft 150A side and the male rotor 110 side, and then grooves are formed in the gap 143 of the drive motor 140 and the outer peripheral surface of the motor stator 142. It flows through the flow path formed by 142b. Thereby, the heat generated from the drive motor 140 is efficiently absorbed. The oil OL that has passed through the drive motor 140 falls into the oil reservoir OL, but a part of the oil OL is supplied to the meshing portions of the bearings 161 and 162 and the synchronous gears 170A and 170B for lubrication and then into the oil reservoir OL. Fall into. Although the temperature of the oil OL falling into the oil reservoir OL has risen, it is cooled to a predetermined temperature by the cooling device 190 in the oil reservoir OL. Although only the male rotor 110 has been described, a similar oil circulation system can be employed for the female rotor 120.

The amount of oil OL that can be supplied for lubrication and cooling by the oil supply component 5000 is limited to some extent because it depends on the rotational speed. By providing the support member 200 and the oil amount adjusting ring 220, a limited amount of oil OL can be efficiently used for lubrication and cooling, and temperature rise of the screw vacuum pump 100 can be prevented. As a result, the screw vacuum pump 100 can be operated at high speed.

Second embodiment (oil circulation system)
Next, an oil circulation system with higher cooling efficiency will be described with reference to FIGS. In addition, the same code | symbol is used for the component similar to 1st Embodiment. An oil reservoir 300A shown in FIG. 20 is disposed concentrically in a closed space CS, a tank 301 formed of a heat insulating material, a bottom plate 304 provided inside the tank 301 and forming a closed space CS together with the tank 301. A plurality of first partition members 305 for forming the oil OL flow path, and a second partition member 306 disposed in the radial direction of the tank 301 for forming the oil OL flow path. ing. The upper portion of the tank 301 has an oil outlet 302 that is inserted into the lower end of the rotary shaft 150 and communicates with the oil supply path of the rotary shaft 150A, and an inlet 303 into which the recovered oil flows. The inflow port 303 is disposed in the outermost peripheral region R 1 of the tank 301, and the oil outflow port 302 is disposed in the central region R 2 of the tank 301. The cooling liquid 320 flows to the bottom of the tank 301, and the cooling liquid 320 of the cooler is in full contact with the bottom plate 304.

In order to increase the heat exchange efficiency of the oil OL flowing through the closed space CS as shown in FIG. 21, the oil OL flow by the oil circulation should be designed to be a turbulent flow with about 2000 to 3000 lay nozzles. preferable. Further, it is preferable that the flow passage cross-sectional area of the oil OL is constant so that the number of lay nozzles is constant in the tank 301.

Here, it is known that when the oil OL is pushed up into the rotary shaft 150A, the amount of oil pushed up by the oil supply component 5000 increases. For example, a part of the tank 301 is formed of a flexible material, the flexible part is pressed from the outside of the tank 301 to be elastically deformed, and the volume of the closed space CS is reduced, so that the oil OL is contained in the rotary shaft 150. Can be pushed up toward

Alternatively, as shown in FIG. 22, a plunger device 340 is provided in the tank 300 </ b> A, and an auxiliary tank 330 is connected to the inlet 303 via a backflow prevention mechanism 340. The rear end portion of the plunger rod 342 to which the plunger tip 341 of the plunger device 340 is connected to the tip is connected to the piston rod 361 of the cylinder device 360 so that the plunger tip 341 can reciprocate. As the plunger tip 341 is advanced, the volume of the closed space CS decreases and the oil OL is pushed up into the rotary shaft 150. At this time, the oil OL in the tank 301 does not flow back through the inflow port 303 by the backflow prevention mechanism 340. Further, when the plunger tip 341 is retracted, the oil OL recovered in the auxiliary tank 330 is present, so that the oil OL in the rotating shaft 150 can be prevented from returning into the oil tank 301.

Further, a lifting head 180 similar to the tapered lifting head 1182 shown in FIG. 1B is provided at the lower end of the oil supply component according to the present invention. The drive screw is fixed to the push-up head 180. However, the drive screw can be provided above the push-up head 180 and fixed to the rotary shaft 150A. By combining the push-up head 180 and the oil supply component 5000, the oil supply amount can be further increased.
In FIG. 1B, 1001 is a rotating shaft, 1002 is oil, 1003 is an oil supply regulating member, 1004 is an oil supply path, 1005 is a tapered inner wall surface, 1006 is a tapered lower end opening, and 1007 is an oil supply path upper end opening.
When using with an external pump, oil is supplied toward the tapered lower end opening 1006 through the oil supply path 1004.
The supplied oil rises on the tapered inner wall surface 1005 by adding the rotational force of the rotary shaft 1001 to the supply driving force.

As mentioned above, although embodiment of this invention was described in detail, referring an accompanying drawing, this invention is not limited to this example. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1100 ... Screw vacuum pump 1110 ... Male rotor 1111 ... Screw gear part 1111a ... Unequal lead unequal inclination angle screw part 1111b ... Equal lead screw part 1112 ... Rotor hollow part 1120- .. Female rotor 1121... Screw gear portion 1121a... Unequal lead unequal inclination angle screw portion 1121b... Equal lead screw portion 1122... Rotor hollow portion 1130... Stator 1131. Part 1132 ... 1st support part 1133 ... 2nd support part 1134 ... Intake port 1135 ... Exhaust port 1140A ... Drive motor 1140B ... Drive motor 1150A ... Rotating shaft 1150B ...・ Rotating shaft 1151A ... Flange 1151B ... 1160Aa ... Bearing bearing 1160Ab ... Bearing bearing 1160Ac ... Bearing bearing 1160Ba ... Bearing bearing 1160Bb ... Bearing bearing 1160Bc ... Bearing bearing 1170A ... Gear 1180 ... Oil supply means 1181 ... Oil reservoir 1182 ... Push-up head 1183 ... Oil flow path 1190 ... Cooling device 1191 ... Cooling pipe 1192 ... Cooling pump 1001 ... Rotating shaft 1002 ... Oil 1003 ... Oil supply regulating member 1004 ... Oil supply path 1005 ... Non-tapered wall surface 1006 ... Tapered lower end opening 1007 ... Oil supply path upper end opening 2000, 3000 ... Oil supply device 2001 ... Times Shaft 2001a ... Oil flow path 2002 ... Oil reservoir 2003 ... Push-up head 2004 ... Outflow portion 2005 ... Outlet 2006 ... Discharge port 2007 ... Inlet port 2008 ... Oil 2009 ... Oil liquid level 3001 ... shaft rod 3002 ... bearing 3003 ... shaft rod rotation stop 3004a, 3004b, 3004c, 3004d ... fixed screw 3005 ... drive screw 5000 ... oil supply component 5001... Rotating shaft 5002... Shaft rod 5003... Bearing 5004... Shaft rod rotation stop 5005... Drive screw 5006 a, 5006 b, 5006 c, 5006 d ...... Fixed screw 5007 a, 5007 b, 5007 c, 5007 d ... Outflow passage 5008 ... Oil flow passage 6 01 ... Wall surface without rotating shaft 7000 ... Fixed screw 8000A, 8000B ... Drive screw 100 ... Screw vacuum pump 110 ... Male rotor 111 ... Screw teeth 111a ... Unequal Lead unequal inclination angle screw part 111b ... Equal lead screw part
111c ... Connection portion 113a ... Hollow portion 113b ... Hollow portion 114 ... Flat plate portion 114h ... Mounting hole 115 ... Disk portion 115h ... Mounting hole 120 ... Female rotor 121 .. Screw teeth 121a ... Unequal lead Unequal inclination angle screw part 121b ... Equal lead screw part
130 ... Stator 135 ... Intake port 136 ... Exhaust port 140 ... Drive motor 141 ... Motor rotor 142 ... Motor stator 142a ... Outer peripheral surface 142b ... Channel groove 143 ··· Gap 150, 150A · · · Rotating shaft 152, 152a ··· Oil supply path 156 ··· Closing member 160, 161, 162 ··· Bearing 180 ··· Lifting head 190 ··· Cooling device 200 · · .. Support members (channel members, guide members)
201 ... 1st flow path 201a ... Inlet 202 ... 2nd flow path 202a ... Inlet 210 ... Receiving plate 220 ... Oil amount adjustment ring 230 ... Shaft seal device 231 ... Holding member 232 ... First seal assembly 233a ... First lip seal 233b ... Second lip seal 234 ... Second seal assembly 234a ... Lip seal 235 ... Labyrinth seal
OL ... Oil M ... Screw

Claims (6)

1. A rotor having at least one screw groove on the outside and having a hollow portion opened at a lower end surface in the rotation axis direction, a stator having a gas intake port and an exhaust port, and housing the rotor; A rotating shaft that is formed as a part and at least a part of which is accommodated in the hollow part; and a bearing that is accommodated in the hollow part and rotatably supports the rotating shaft. The shaft has a first oil supply passage that extends in the longitudinal direction and opens in the lower end portion and the hollow portion, and the oil supply passage is a second oil supply passage that opens on the outer surface of the rotating shaft. An oil supply component for a screw exhaust pump that communicates,
   The rotating shaft, and a helical structure capable of exhibiting a pumping function in the rotating shaft,
   The structure is composed of a drivable spiral structure located below the rotary shaft and a fixed spiral structure located above the structure, and an oil supply component for a screw exhaust pump. .
2. A male rotor and a female rotor having screw teeth that mesh with each other;
   A stator having a gas inlet and an outlet and accommodating the male and female rotors;
   At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
   A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion;
   A bearing housed in the hollow portion and rotatably supporting the rotating shaft;
   The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end portion and a hollow portion,
   An oil reservoir disposed below the stator, storing oil to be supplied to an oil supply path of the rotating shaft, and collecting oil supplied into the hollow portion through the oil supply path;
   At least a portion is disposed between the rotating shaft and an inner wall surface of the at least one rotor that defines the hollow portion, and is fixed to the stator and supplied to the hollow portion through the oil supply path. An oil supply component for a screw exhaust pump, having a flow path member that defines a plurality of oil flow paths for distributing and flowing oil into a plurality of flow paths in the hollow portion,
   The rotating shaft and a helical structure capable of exhibiting a pumping function in the rotating shaft,
   The oil supply component for a screw exhaust pump, wherein the structure is composed of a drivable spiral structure positioned below the rotary shaft and a fixed spiral structure positioned above the structure.
3. A male rotor and a female rotor having screw teeth that mesh with each other;
   A stator having a gas inlet and an outlet and accommodating the male and female rotors;
   At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
   A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion;
   A bearing housed in the hollow portion and rotatably supporting the rotating shaft;
   The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end portion and a hollow portion,
   An oil supply component for a screw exhaust pump having an oil amount adjusting mechanism that is provided for the bearing and adjusts the supply amount of oil supplied to the bearing through the oil supply path,
   The rotating shaft, and a helical structure capable of exhibiting a pumping function in the rotating shaft,
   The oil supply component for a screw exhaust pump, wherein the structure is composed of a drivable spiral structure positioned below the rotary shaft and a fixed spiral structure positioned above the structure.
4. A male rotor and a female rotor having screw teeth that mesh with each other with a predetermined gap;
   A stator having a gas inlet and an outlet and accommodating the male and female rotors;
   At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
   A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion;
   The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end portion and a hollow portion,
   A motor rotor fixed to the rotating shaft; and a motor stator disposed around the motor rotor; and at least a part of the hollow portion being disposed and a driving motor integrally provided on the rotating shaft. ,
   A screw exhaust pump having a guide member for guiding oil supplied through an oil supply path of the rotating shaft that rotates to a gap between a motor rotor and a motor stator of the drive motor and an outer peripheral surface of the motor stator. Oil supply parts,
   The rotating shaft, and a helical structure capable of exhibiting a pumping function in the rotating shaft,
   The oil supply component for a screw exhaust pump, wherein the structure is composed of a drivable spiral structure positioned below the rotary shaft and a fixed spiral structure positioned above the structure.
5. A male rotor and a female rotor having screw teeth that mesh with each other;
   A stator having a gas inlet and an outlet and accommodating the male and female rotors;
   At least one of the male rotor and the female rotor has a hollow portion that opens at a lower end surface in the rotation axis direction;
   A rotating shaft coupled to the at least one rotor and at least partially housed in the hollow portion and rotatably supported;
   The rotating shaft has an oil supply path that extends in a longitudinal direction and opens in a lower end surface and a hollow portion,
   An oil reservoir disposed below the stator for storing oil to be supplied through an oil supply path of the rotary shaft and for collecting oil supplied into the hollow portion through the oil supply path of the rotary shaft; There,
   A partition that defines a closed space for filling the oil;
   A change element that defines a part of the closed space and is capable of changing a volume of the closed space;
   An oil outlet that communicates with the oil supply path of the rotating shaft;
   An oil inlet into which oil recovered after being supplied into the hollow portion through the exhaust port of the rotating shaft;
   A pressure mechanism for operating the change element to pressurize the oil in the closed space in order to push up the oil filled in the closed space toward the oil supply path of the rotary shaft through the oil outlet. An oil reservoir having,
   An oil supply component for a screw exhaust pump having
   The rotating shaft;
   A helical structure capable of exhibiting a pumping function in the rotating shaft,
   The oil supply component for a screw exhaust pump, wherein the structure is composed of a drivable spiral structure positioned below the rotary shaft and a fixed spiral structure positioned above the structure.
6. A screw exhaust pump comprising any one of the oil supply parts for the screw exhaust pump according to claim 1.

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