JP3716890B2 - Cooling device for vacuum motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vacuum motor used in an actuator for carrying and handling a sample such as a semiconductor manufacturing apparatus and a liquid crystal manufacturing apparatus in a vacuum chamber, and more particularly to a cooling apparatus for a vacuum motor.
[0002]
[Prior art]
Conventionally, for example, in a semiconductor manufacturing process in a vacuum environment, a vacuum motor used in a power transmission device for wafer transfer has a temperature rise due to heat generated by an armature winding wound around a stator core compared to the atmosphere. Therefore, sufficient cooling is required without polluting the vacuum environment.
A conventional cooling device for a rotary type vacuum motor will be described. FIG. 3 is a sectional view of the same apparatus showing a first conventional example. The vacuum motor 1 includes a cylindrical frame 2, a stator core 3 having an armature winding 31 provided inside the frame 2, and a load 11 at one end supported by a bearing 6 inside the frame 2. And a rotor 4 fitted on the outside of the rotary shaft 5 and provided via a gap. The vacuum motor 1 is placed in a vacuum chamber 8 connected to an evacuation device (not shown), and a base made of a heat conducting member fixed horizontally on the inner peripheral wall surface of the vacuum chamber 8. is set up. In the vacuum motor 1 having such a configuration, heat generated in the armature winding 31 and the bearing 6 wound around the stator core 3 is transmitted to the frame 2 and is vacuumed via the base 7 attached to the frame 2. Heat is transferred to the outer peripheral wall surface of the chamber 8 to be cooled.
Further, as a second conventional example, a pipe connected to the atmosphere side outside the vacuum chamber is embedded in a water cooling jacket provided in the frame portion, and a liquid such as water is allowed to flow through the pipe, thereby There has been proposed a cooling device that dissipates heat by heat transfer by circulating the liquid generated by the armature winding through a liquid and circulating the liquid through a chiller or the like.
As a third conventional example, working fluid is enclosed in a frame part, and heat generated in the armature winding of the motor is carried to a condensing part at a position separated by evaporation of the working fluid. Has been proposed (for example, JP-A-7-236256).
FIG. 4 is a sectional view of a cooling device for a vacuum motor showing a third conventional example. In the figure, differences from the first conventional example will be described. An annular cavity 12 is formed in the frame 2 that surrounds the periphery of the stator core 3 that generates heat. The annular cavity 12 serves as an evaporating portion for evaporating the working fluid. One end of the pipe 13 and the liquid flow passage pipe 14 are connected to communicate with the cavity 12. The other end portions of the steam passage pipe 13 and the liquid passage pipe 14 extend to the outside through the outer wall portion of the vacuum chamber 8, and communicate with the condensing portion 15 on the outside. And is detachably connected. Further, working fluid such as water or chlorofluorocarbon is sealed in the cavity portion 12, the steam passage pipe 13, the liquid passage pipe 14, and the condensing portion 15. A wick 12 a made of a wire mesh or the like that performs capillary action is stretched on the inner peripheral wall of the cavity portion 12. Here, 13a and 14a are a steam passage and a liquid passage pipe on the motor side, respectively, and 13b and 14b are a steam passage and a liquid passage pipe on the condenser side, respectively.
In such a configuration, when the armature winding 31 generates heat due to the operation of the vacuum motor 1, this heat is transmitted to the cavity portion 12 via the inner wall portion of the frame 2, and the working fluid of the wick 12 a in the cavity portion 12. Is removed by evaporation. Due to the evaporation of the working fluid, the air pressure in the cavity portion 12 becomes higher than the air pressure in the condensing portion 15, and a pressure difference is generated between the two portions. Then, it is moved into the condensing part 15 through the steam passage pipe 13, and the latent heat of evaporation is discharged to the outside through the condensing part 15 to condense. It is trying to return to.
[0003]
[Problems to be solved by the invention]
However, in the vacuum motor cooling apparatus of the first conventional example, when the vacuum motor 1 with the load 11 attached to the end of the rotary shaft is rotated, the armature winding that is the main heat generating part of the vacuum motor 1 The heat is radiated from the outer peripheral wall surface of the vacuum chamber 8 through the base 7 to which the frame 2 is fixed under the influence of the Joule heat of 31 and the frictional heat of the bearing. As the radiant heat from the armature winding 31 or the stator core 3, there is a path of heat transfer to the stator core 3 and the rotor 4 through the gap and the rotating shaft 5 that fits the rotor 4. The heat of the heat transfer path causes the temperature of the rotor 4 and the rotating shaft 5 to rise and cause deformation, or the temperature of the rotating shaft 5 causes the bearing 6 that is a contact element to deform. There was a problem of causing damage.
In the cooling devices shown in the second conventional example and the third conventional example, the heat on the stator core 3 side can be forcibly transferred to the outside of the vacuum chamber 8 to dissipate heat. Heat is transmitted to the rotor 4 by the radiant heat of the wire 31 or the stator core 3, or heat generated by the load 11 of the rotating shaft 5 is transmitted to the rotating shaft 5, and the temperature of the rotor 4 and the rotating shaft 5 rises. There was a problem.
In addition, since the third conventional example is connected by a cooling pipe, the heat transport path becomes long and the structure becomes complicated, and the cooling pipe connected to the motor body is removed from the vacuum chamber 8 at the time of disassembling and assembling maintenance. There is also a problem that work must be performed and the workability is poor and the cost is high.
Accordingly, the first object of the present invention is to efficiently dissipate the heat generated in the armature winding and the bearing to the outside of the vacuum chamber in a vacuum, thereby solving problems such as deformation of the rotating shaft or damage to the bearing. An object of the present invention is to provide a cooling device for a vacuum motor that can be used.
A second object of the present invention is to provide a cooling device for a vacuum motor that eliminates the work of disassembly and assembly such as maintenance of the cooling device and has a simple structure that does not require work costs.
[0004]
[Means for Solving the Problems]
In order to solve the above problem, the present invention includes a vacuum chamber, a base fixed on the inner peripheral wall surface of the vacuum chamber, and a vacuum motor installed through the base, The vacuum motor is supported at one end by a frame provided in a direction perpendicular to the base, a stator core having an armature winding provided on the inside of the frame, and a bearing on the inside of the frame. In a cooling device for a vacuum motor, which includes a rotating shaft connected to a load, and a rotor that is fitted outside the rotating shaft and provided via the stator core and a gap, the rotating shaft is anti-load The frame is formed in a cup shape having a hollow portion drilled from the side toward the load side, and the frame has a base having a hole portion larger than the shaft diameter of the rotating shaft on the end surface on the non-load side. A mounting surface is formed and the base A coaxial fixed shaft for heat transfer is provided on the upper surface of the base plate through a slight gap from the hole provided between the base mounting surfaces toward the end surface on the load side of the hollow portion. It is a thing.
The fixed shaft for heat transfer is provided with a cooling passage through which a cooling fluid flows.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described with reference to the embodiments shown in the drawings.
FIG. 1 is a sectional view of a vacuum motor showing a first embodiment of the present invention. The same components as those in the conventional example are denoted by the same reference numerals, and the description thereof is omitted.
The configuration in which the vacuum motor 1 is fixed to the base 7 in the vacuum chamber 8 is the same as that of the first conventional example. The difference from the conventional example is that in the vacuum motor 1, the rotating shaft 5 is made of a cup having a hollow portion 51 drilled from the anti-load side toward the load side. A base mounting surface 22 having a hole 21 larger than the shaft diameter of the rotary shaft 5 is formed on the end surface of the base 7, and a hole provided between the base mounting surfaces 22 is formed on the upper surface of the base 7. A coaxial heat transfer fixed shaft 9 is provided from 21 to the end surface on the load side of the hollow portion 51 via a rotating shaft 5 and a slight gap. The fixed shaft 9 for heat transfer is made of a highly heat conductive material.
The operation in such a configuration will be described.
When the vacuum motor 1 with the load 11 attached to the end of the rotary shaft is rotated inside the vacuum chamber 8, the heat generated from the armature winding 31 and the bearing 6 is transferred to the frame 2, and the base 7 is moved from the frame 2 to the base 7. Then, heat is radiated from the outer peripheral wall surface of the vacuum chamber 8. Further, heat is transmitted to the rotor 4 through the stator core 3 and the air gap as radiant heat from the armature winding 31 or the stator core 3. The heat transmitted to the rotor 4 conducts heat to the rotating shaft 5 fitted to the inner periphery of the rotor 4, and radiates to the fixed shaft 9 for heat transfer provided through the rotating shaft 5 and a slight gap. Then, the heat is transferred from the fixed heat transfer shaft 9 to the base 7 and the outer peripheral wall surface of the vacuum chamber 8. The vacuum chamber 8 has a larger heat capacity than the vacuum motor 1, and the outer peripheral wall surface of the vacuum chamber 8 is in contact with the atmosphere, so that heat is radiated by natural convection and the temperature increase of the vacuum motor 1 is suppressed.
Therefore, the heat generated from the armature winding 31 and the like due to the operation of the vacuum motor 1 is transferred from the frame 2 of the stator core 3 to the vacuum chamber 8, and from the inside of the rotary shaft 5, the fixed shaft for heat transfer. Since the heat is transferred to the rotor 9 by radiant heat, the heat generated in the rotor 4, the rotating shaft 5 and the bearing 6 is efficiently radiated to the outside of the vacuum chamber 8, and further, deformation due to a temperature rise of the rotating shaft 4 or damage to the bearing 6. The problem can be solved.
[0006]
FIG. 2 is a sectional view of a vacuum motor showing a second embodiment. The difference from the first embodiment is that a cooling passage 10 is arranged inside the fixed shaft 9 for heat transfer. Both ends of the cooling passage 10 are connected to a chiller (not shown).
In such a configuration, since the cooling water circulates inside the heat transfer fixed shaft 9 by circulating the cooling water from the chiller (not shown) to the cooling passage 10, the armature winding of the vacuum motor 1 The heat transferred to the rotating shaft by the heat generated from the heat is exchanged with the cooling water circulating in the fixed shaft 9 for heat transfer.
Therefore, the temperature rise due to the heat generated in the rotor 4, the rotating shaft 5, and the bearing 6 can be further suppressed, and heat can be efficiently radiated to the outside of the vacuum chamber 8.
In addition, because of the simple structure in which the cooling passage 10 is disposed inside the heat transfer fixed shaft 9 fixed to the base 7, disassembly such as maintenance as a cooling device and work at the time of assembly are eliminated, and work costs are not incurred. There is an effect of obtaining a cooling device for a vacuum motor.
[0007]
【The invention's effect】
As described above, according to the present invention, the heat generated by the operation of the vacuum motor is not conducted from the fixed side of the frame or the like as in the prior art, but a little from the inside of the rotary shaft having the hollow portion. Since the heat transfer fixed shaft installed via the air gap is configured to take into account the heat transfer path as radiant heat, the vacuum chamber can efficiently transfer the heat generated by the armature windings and bearings in a vacuum. There is an effect of obtaining a cooling device for a vacuum motor that can radiate heat to the outside. Thereby, the problem of the deformation of the rotating shaft or the breakage of the bearing can be solved.
In addition, since work such as maintenance and cooling of the cooling device can be eliminated, work costs are not required, and the structure can be simplified.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a cooling device for a vacuum motor showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view of a cooling device for a vacuum motor showing a second embodiment of the present invention.
FIG. 3 is a cross-sectional view of a cooling device for a vacuum motor showing a first conventional example.
FIG. 4 is a cross-sectional view of a cooling device for a vacuum motor showing a third conventional example.
[Explanation of symbols]
1: Vacuum motor 2: Frame 21: Hole 22: Frame mounting surface 3: Stator core 31: Armature winding 4: Rotor 5: Rotating shaft 51: Hollow portion 6: Bearing 7: Base 8: Vacuum chamber 9: Heat transfer fixed shaft 10: Cooling passage 11: Load

Claims (2)

A vacuum chamber, a base fixed on the inner peripheral wall surface of the vacuum chamber, and a vacuum motor installed through the base, the vacuum motor being perpendicular to the base A frame provided in a direction, a stator core having an armature winding provided inside the frame, a rotating shaft supported via a bearing inside the frame and connected to a load, and a rotating shaft of the rotating shaft In a cooling device for a vacuum motor, which is configured by a rotor that is fitted on the outside and provided with a stator core and a rotor provided through a gap,
The rotating shaft is formed in a cup shape having a hollow portion drilled from the anti-load side toward the load side, and the frame has an end surface on the anti-load side larger than the shaft diameter of the rotating shaft. A base mounting surface having a hole is formed, and an upper surface of the base is formed on a top surface of the base from a hole formed between the base mounting surfaces toward an end surface on the load side of the hollow portion. A cooling device for a vacuum motor, characterized in that a fixed shaft for heat transfer is provided coaxially with a rotating shaft and a slight gap. The cooling device for a vacuum motor according to claim 1, wherein the fixed shaft for heat transfer is provided with a cooling passage through which a cooling fluid flows.

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