JP5156640B2 - Vacuum pump - Google Patents

Description

  The present invention relates to a vacuum pump, for example, a vacuum pump that performs exhaust processing of a vacuum vessel.

Vacuum pumps such as turbo molecular pumps and thread groove pumps are widely used, for example, in vacuum vessels that require high vacuum such as exhaust of semiconductor manufacturing equipment and electron microscopes.
A vacuum pump that realizes this high vacuum environment includes a casing that forms an exterior body having an intake port and an exhaust port. And the structure which makes the said vacuum pump exhibit an exhaust function is accommodated in the inside of this casing. A structure that exhibits this exhaust function is roughly composed of a rotating part (rotor part) that is rotatably supported and a fixed part (stator part) fixed to the casing.

The rotating part is composed of a rotating shaft and a rotating body fixed to the rotating shaft, and the rotating body is provided with rotor blades arranged radially and in multiple stages. Further, stator blades are arranged in multiple stages in the fixed portion alternately with respect to the rotor blades.
The turbo molecular pump is provided with a motor for rotating the rotating shaft at a high speed, and when the rotating shaft rotates at a high speed by the function of this motor, gas is sucked from the intake port by the action of the rotor blade and the stator blade, It is discharged from the exhaust port.
Various operations of the pump body configured as described above are controlled by a control device (control unit).

The pump body and the control device as described above are connected via a dedicated cable. Since this dedicated cable is thick with many signal wires and power supply wires bundled together, the cable cannot be easily routed.
Further, in an environment where the pump main body and the control device are arranged far away from each other, the dedicated cable inevitably becomes long, so that the signal may be attenuated while passing through the cable.
Conventionally, in order to eliminate the problems caused by such a dedicated cable, the technology for connecting the pump body and the control device without using the dedicated cable, that is, the technology for integrating the pump body and the control device is described in the following patent document. 1 is proposed.

Moreover, the vacuum pump kept the pump main body high temperature (about 60-80 degreeC) in order to suppress the accumulation of the product in a gas transfer path. Therefore, in a vacuum pump in which the pump body and the control device are integrated, there is a possibility that condensation occurs inside the control device when the control device is cooled to prevent overheating.
Therefore, in a vacuum pump in which the pump main body and the control device are integrated, a technique for dissipating heat inside the control device while suppressing condensation is proposed in Patent Document 2 below.
JP-A-11-173293 JP 2006-90251 A

By the way, in the vacuum pump proposed in Patent Document 2, heat is radiated to the outside through the casing by disposing the heating element so as to be in contact with the casing.
For this reason, it has been difficult to cool the control circuit disposed in the region not in contact with the housing.
Therefore, an object of the present invention is to provide a vacuum pump capable of improving the cooling efficiency of a control circuit in a control device of a vacuum pump in which a pump body and a control device are integrated.

The invention according to claim 1 includes a pump main body including a gas transfer mechanism for transferring gas from an inlet port to an exhaust port, a control circuit mounted on the pump main body and controlling the pump main body, and the inside is sealed. a vacuum pump and a control device, comprising a having been casing, wherein the control device comprises a forced convection generating means for generating a forced flow in the housing of the fluid, the said control device The housing has a flow hole communicating with a fluid flow path in the housing on a side surface, a first housing portion containing the control circuit, and a second housing disposed so as to cover the flow hole. The second casing part is detachably provided to the first casing part to achieve the object.
According to a second aspect of the present invention, in the vacuum pump according to the first aspect, the control circuit has a heating element that is heated by self-loss, and the control device absorbs heat generated by the control circuit. And a cooling means for cooling the heat exchange mechanism.
According to a third aspect of the invention, the vacuum pump 請 Motomeko 2, wherein the heat exchange mechanism is characterized by configuring the flow path of the housing of the fluid.
Invention of claim 4, the vacuum pump 請 Motomeko 2 or claim 3, wherein the control device, the control circuit is mounted, comprising a control substrate constituting a flow path of the housing of the fluid The heat exchange mechanism absorbs heat of the control board.
According to a fifth aspect of the present invention, in the vacuum pump according to the fourth aspect, the control boards are stacked via a gap, and the adjacent control boards constitute a fluid flow path in the housing. And
A sixth aspect of the present invention is the vacuum pump according to any one of the second to fifth aspects, wherein the cooling means is provided in the second casing portion. To do.
A seventh aspect of the present invention is the vacuum pump according to any one of the first to sixth aspects, wherein the control device is mounted on the pump main body via a heat insulating means. And

  According to the present invention, the cooling efficiency of the control circuit can be improved by forcibly causing a flow in the fluid in the casing of the control device.

It is the figure which showed schematic structure of the turbo-molecular pump which concerns on this embodiment. It is the perspective view which showed schematic structure of the control apparatus which concerns on this Embodiment. It is the figure which showed the flow of the air inside a control apparatus at the time of utilization of a 1st cooling system. It is the figure which showed the flow of the air inside a control apparatus at the time of utilization of a 2nd cooling system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Turbo molecular pump 2 Casing 3 Base 4 Rotor part 5 Intake port 6 Exhaust port 7 Shaft 8 Rotor blade 9 Cylindrical member 10 Bolt 11 Motor part 12-14 Magnetic bearing part 15-17 Displacement sensor 18 Stator blade 19 Screw groove spacer 20 Spacer DESCRIPTION OF SYMBOLS 21 Stator column 22 Back cover 23 Connector part 24 Control apparatus 25 Baking heater 26 Cooling pipe 30 Housing | casing 31a-d Side wall 31e Partition plate 32 Exhaust hole 33 Intake hole 34 Through-hole 40 Fan 50 Cooling jacket 51 Cooling pipe 52 Communication path 60 Heat Exchange fin 70 Control board 71 Spacer 81 Upper lid 82 Lower lid 90 Thermal insulation member

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS. In this embodiment, a turbo molecular pump is used as an example of a vacuum pump.
FIG. 1 is a diagram showing a schematic configuration of a turbo molecular pump 1 according to the present embodiment. 1 shows a cross-sectional view of the turbo molecular pump 1 in the axial direction.
In the present embodiment, a so-called composite wing type molecular pump including a turbo molecular pump part T and a thread groove type pump part S will be described as an example of a turbo molecular pump.
The turbo molecular pump 1 is a vacuum pump that exhibits an exhaust function by an exhaust action of a rotor portion that rotates at high speed and a fixed stator portion, and has a turbo molecular pump, a thread groove pump, or a structure of both of these. There are pumps that have both.

The casing 2 forming the outer casing of the turbo molecular pump 1 has a cylindrical shape, and constitutes the outer casing of the turbo molecular pump 1 together with the base 3 provided at the bottom of the casing 2. A structure that allows the turbo molecular pump 1 to perform an exhaust function, that is, a gas transfer mechanism, is accommodated inside the exterior body of the turbo molecular pump 1.
These structures that exhibit the exhaust function are roughly composed of a rotor portion 4 that is rotatably supported and a stator portion that is fixed to the casing 2.
Further, the intake port 5 side is constituted by a turbo molecular pump part T, and the exhaust port 6 side is constituted by a thread groove type pump part S.

The rotor section 4 is provided with rotor blades 8 made of blades extending radially from the shaft 7 at a predetermined angle from a plane perpendicular to the axis of the shaft 7 on the intake port 5 side (turbo molecular pump section T). ing. The rotor portion 4 is made of a metal such as stainless steel or aluminum alloy.
Furthermore, the rotor part 4 is provided with a cylindrical member 9 made of a member whose outer peripheral surface is cylindrical on the exhaust port 6 side (screw groove type pump part S).
The turbo molecular pump 1 has a plurality of rotor blades 8 formed in the axial direction.

The shaft 7 is a rotating shaft (rotor shaft) of the cylindrical member. The rotor portion 4 is attached to the upper end of the shaft 7 with a plurality of bolts 10.
A motor unit 11 that rotates the shaft 7 is disposed in the middle of the shaft 7 in the axial direction.
Further, a magnetic bearing portion 12 and a magnetic bearing portion 13 for supporting the shaft 7 in the radial direction are provided on the intake port 5 side and the exhaust port 6 side of the motor unit 11.
Furthermore, a magnetic bearing portion 14 for supporting the shaft 7 in the axial direction (thrust direction) is provided at the lower end of the shaft 7.
The shaft 7 is supported in a non-contact manner by a 5-axis control type magnetic bearing composed of the magnetic bearing portions 12, 13, and 14.
Displacement sensors 15 and 16 are formed in the vicinity of the magnetic bearing portions 12 and 13, respectively, so that the displacement of the shaft 7 in the radial direction can be detected. Further, a displacement sensor 17 is formed at the lower end of the shaft 7 so that the displacement of the shaft 7 in the axial direction can be detected.

A stator portion is formed on the inner peripheral side of the casing 2. This stator portion is composed of a stator blade 18 provided on the intake port 5 side (turbo molecular pump portion T), a thread groove spacer 19 provided on the exhaust port 6 side (screw groove type pump portion S), and the like. Yes.
The stator blade 18 is composed of a blade that is inclined by a predetermined angle from a plane perpendicular to the axis of the shaft 7 and extends from the inner peripheral surface of the casing 2 toward the shaft 7. In the turbo molecular pump portion T, the stator blades 18 are formed in a plurality of stages alternately with the rotor blades 8 in the axial direction. The stator blades 18 of each stage are separated from each other by a cylindrical spacer 20.

The thread groove spacer 19 is a cylindrical member having a spiral groove formed on the inner peripheral surface. The inner peripheral surface of the thread groove spacer 19 faces the outer peripheral surface of the cylindrical member 9 with a predetermined clearance (gap) therebetween. The direction of the spiral groove formed in the thread groove spacer 19 is a direction toward the exhaust port 6 when the gas is transported in the spiral groove in the rotational direction of the rotor portion 4. The depth of the spiral groove becomes shallower as it approaches the exhaust port 6. The gas transported through the spiral groove is compressed as it approaches the exhaust port 6.
These stator parts are made of metal such as stainless steel or aluminum alloy.
The base 3 constitutes an exterior body of the turbo molecular pump 1 together with the casing 2. At the center of the base 3 in the radial direction, a stator column 21 having a cylindrical shape is attached concentrically with the rotation axis of the rotor.

A back cover 22 is attached to the bottom of the base 3 (the opening of the stator column 21). The back cover 22 is provided with a connector portion 23 for drawing out the internal wiring of the turbo molecular pump 1 and connecting it to a control device 24 described later.
In addition, let the area | region (part) which uses the casing 2, the base 3, and the back cover 22 as an exterior body, ie, the part in which the gas transfer mechanism is comprised be a pump main body.
In the turbo molecular pump 1 according to the present embodiment, a control device 24 for controlling the pump body is mounted on the pump body. That is, the pump body and the control device 24 are integrated.
The control device 24 is disposed at the bottom of the base 3 (opening of the stator column 21), that is, in a region facing the back cover 22.

A baking heater 25 is attached to the outer peripheral portion of the thread groove type pump portion S so as to surround the base 3 in the circumferential direction.
The baking heater 25 is composed of an electric heating member such as a nichrome wire and is supplied with electric power by a temperature controller. The baking heater 25 generates heat when electric power is supplied, and heats the thread groove type pump unit S.
Since the gas sucked from the intake port 5 is cooled while the turbo molecular pump unit T is transferred, the temperature of the gas is lowered when transferred to the thread groove type pump unit S. On the other hand, when the gas pressure is transferred to the thread groove type pump section S, it is high. That is, the gas transferred to the thread groove type pump part S is in a low temperature and high pressure state. Therefore, the thread groove type pump part S is in a state where a solid product due to the transferred gas is likely to precipitate.
Therefore, in order to suppress the precipitation of the solid product due to the gas transferred by the thread groove spacer 19, the baking groove 25 is used to keep the thread groove pump section S at a high temperature.

During the operation of the turbo molecular pump 1, the rotor unit 4 rotates at a high speed, and the blades of the rotor blades 8 and the stator blades 18 receive process gas that has become high temperature due to compression heat or the like. Then, the temperature of the blades of the rotor blades 8 and the stator blades 18 rises due to the compression heat and the like.
Further, the turbo molecular pump 1 is heated by heat generated from the motor unit 11 and becomes a high temperature state.
Thus, the pump body is in a high temperature state due to collision heat (compression heat) of gas molecules, heat generation from the motor unit 11, heating by the baking heater 25, and the like.

If the high-temperature heat in the pump body as described above is conducted to the control device 24, there is a risk that a circuit (control circuit) inside the control device 24 will be defective. That is, the internal circuit of the control device 24 may be malfunctioned due to the influence of heat.
Therefore, a cooling pipe 26 is embedded in the base 3 in order to reduce the influence of the heat of the pump body that the control device 24 receives.
The cooling pipe 26 is made of a tubular (tubular) member. The cooling pipe 26 is a member for cooling the periphery of the cooling pipe 26 by flowing a coolant as a heat medium therein and absorbing the heat in the coolant.
By flowing the coolant through the cooling pipe 26, the base 3 is forcibly cooled. Due to this cooling effect, heat conducted from the pump body to the control device 24 can be reduced (suppressed).

The cooling pipe 26 described above is made of a member having a low thermal resistance, that is, a member having a high thermal conductivity, such as copper or stainless steel.
The coolant flowing through the cooling pipe 26, that is, the fluid for cooling the object may be liquid or gas. As the liquid coolant, for example, water, an aqueous calcium chloride solution, an aqueous ethylene glycol solution, or the like can be used. As the gaseous coolant, for example, ammonia, methane, ethane, halogen, helium gas, carbon dioxide gas, air, or the like can be used.
In the present embodiment, the cooling pipe 26 is provided on the base 3, but the arrangement position of the cooling pipe 26 is not limited to this. For example, the stator column 21 and the back cover 22 may be provided so as to be embedded directly.

Next, the structure of the control device 24 mounted on the pump body having the above-described configuration will be described.
FIG. 2 is a perspective view showing a schematic configuration of the control device 24 according to the present embodiment. In FIG. 2, the components constituting the control device 24 are shown separated.
The control device 24 includes a housing 30, a fan (blower) 40, a cooling jacket 50, a heat exchange fin 60, a control board 70, an upper lid 81 and a lower lid 82.
The housing 30 includes four side walls 31a to 31d constituting a frame and a partition plate 31e that divides the inside of the housing (frame) 30 into a first region and a second region.
The first region refers to the upper portion of the partition plate 31e, that is, the region between the partition plate 31e and the upper lid 81, and the second region refers to the lower portion of the partition plate 31e, that is, the partition plate 31e and the lower lid 82. The area between is shown.
The partition plate 31e is formed integrally with the side walls 31a to 31d, and is configured such that the heat of the partition plate 31e moves quickly to the side walls 31a to 31d.
The housing | casing 30 is comprised with members with high heat conductivity, such as aluminum, copper, and aluminum alloy.

The partition plate 31e is provided in a direction orthogonal to the inner side surfaces of the side walls 31a to 31d, that is, in a horizontal direction on the drawing.
The partition plate 31e is formed with a rectangular through hole 34 penetrating in the thickness direction in the vicinity of the end thereof, specifically in the vicinity of the side wall 31a.
The fan 40 is attached so that the air blowing port closes the through hole 34. The blower port refers to an outlet for air blown from the fan 40. The fan 40 functions as a forced convection generating unit.
The side wall 31 d constituting the housing 30 is provided with an exhaust hole 32 communicating with the first region inside the housing 30 and an intake hole 33 communicating with the second region inside the housing 30.

The heat exchange fin 60 has a plurality of fins for increasing the surface area, and is fixed to the partition plate 31e in the first region inside the housing 30. The heat exchange fin 60 functions as a heat exchange mechanism.
The heat exchange fin 60 and the partition plate 31e are fixed (joined) so as to be in surface contact with each other in order to improve the thermal conductivity between them, that is, to increase the heat transfer speed.
The heat exchange fin 60 and the partition plate 31e may be integrally formed.
Further, it is desirable to apply silicon grease to the contact surface between the heat exchange fin 60 and the partition plate 31e, or to dispose a silicon sheet. Thus, by using a member having high thermal conductivity for the contact surface between the heat exchange fin 60 and the partition plate 31e, the thermal conductivity between the two can be further improved.
The upper lid 81 is joined to the housing 30 so as to seal the opening end of the upper part (pump main body side) of the frame.

The control board 70 is a board on which a control circuit is mounted. In the present embodiment, the plurality of control boards 70 are fixed to the partition plate 31e in the second region inside the housing 30.
In the present embodiment, a plurality of control boards 70 are stacked via spacers 71.
The control board 70 closest to the partition board 31e among the stacked control boards 70 is joined (fixed) to the partition board 31e so as to be in surface contact.
In addition, the arrangement interval of the control board 70 can be set to an arbitrary value by adjusting the height of the spacer 71.

Here, the control circuit mounted on the control board 70 will be described.
The control circuit includes a drive circuit for the motor unit 11 and the magnetic bearing units 12 to 14, a power supply circuit, and the like. Further, a circuit for controlling these drive circuits and a storage element storing various information used for controlling the turbo molecular pump 1 are mounted.
The storage element stores information (data) such as pump operation time, error history, temperature control set temperature, and the like as pump information.
In general, an environmental temperature in consideration of reliability is set for an electrical component (element) used in an electronic circuit. For example, the environmental temperature of the memory element described above is approximately 60 ° C. Such an element having low heat resistance is expressed as a low heat resistance element.

Each electrical component must be used within the set range of the environmental temperature during the operation of the turbo molecular pump 1.
In addition to the above-described low heat resistance element, many circuits (power elements) that generate heat due to internal loss (internal loss) are used in the circuit provided in the control device 24. For example, the transistor element which comprises the inverter circuit which is a drive circuit of the motor part 11 etc. correspond to this.
The environmental temperature is also set in such an element that increases the amount of self-heating. For this reason, in the present embodiment, such an element that generates a large amount of heat is mounted on the control board 70 closest to the partition plate 31e so that heat is easily discharged (released).
The lower lid 82 is joined to the housing 30 so as to seal a lower opening end of the frame.
Note that the structure formed by the casing 30, the upper lid 81, and the lower lid 82 functions as a first casing portion.

The cooling jacket 50 is fixed to the formation surface of the side wall 31d of the housing 30 by a fastening member such as a bolt. The cooling jacket 50 functions as a second housing part.
In the present embodiment, the cooling jacket 50 is configured to be easily detachable from the housing 30 by removing the fastening member, that is, detachable.
The cooling jacket 50 is embedded with a cooling pipe 51 for water cooling similar to the cooling pipe 26 described above.
The cooling jacket 50 is cooled by flowing a coolant through the cooling pipe 51, and the casing 30 in contact with the cooling jacket 50 is forcibly cooled.
As shown in FIG. 1, the cooling jacket 50 is formed with a concave communication path 52 that communicates the exhaust hole 32 and the intake hole 33 with the side wall 31 d of the housing 30.
The cooling jacket 50 is mounted so as to cover the exhaust hole 32 and the intake hole 33 of the side wall 31 d of the casing 30, that is, the casing 30 is configured to be sealed by the cooling jacket 50.

In the present embodiment, the cooling pipe 26 is disposed on the base 3 of the pump body in order to efficiently reduce the heat transferred from the pump body to the control device 24.
However, when the forced cooling is partially performed using the cooling pipe 26 as in the present embodiment, condensation may occur in the cooling portion.
This dew condensation is a phenomenon in which water droplets appear on the cooling surface when the cooling part (cooling surface) falls below the dew point (temperature at which the relative humidity becomes 100%).
When such dew condensation occurs in the control device 24, there is a risk of causing a malfunction in the control circuit.

Therefore, in the present embodiment, the control device 24 is screwed and fixed to the pump body via a washer-like heat insulating member 90 in order to suppress dew condensation in the control device 24. That is, the heat insulating member 90 is disposed between the pump body and the control device 24.
The heat insulating member 90 is disposed in a portion (region) that comes into contact with the pump body when the control device 24 is attached to the pump body.
The heat insulating member 90 is made of a material having a high thermal resistance such as rubber, plastic, foam, ceramic, that is, a material having a low thermal conductivity.
In addition, the control device 24 may be fixed via a gap (specifically, a spacer) without being closely attached to the pump body. In this case, the gap between the pump body and the control device 24 functions (acts) as the heat insulating member 90.

By disposing the heat insulating member 90 in this way, the pump body and the control device 24 can be thermally insulated (separated). That is, by providing the heat insulating member 90, it is possible to suppress (reduce) the influence of cooling by the cooling pipe 26 received by the control device 24.
Thereby, since the sudden temperature difference between a pump main body and the control apparatus 24 can be buffered, it can avoid that the inside of the control apparatus 24 will be in the state cooled to below a dew point.
Therefore, it is possible to appropriately suppress the occurrence of dew condensation in the control device 24.
The thermally insulated pump body and the control device 24 perform temperature management independently (individually).
Specifically, in the pump main body, the temperature management is performed by adjusting the refrigerant flowing through the cooling pipe 26 or adjusting the set temperature of the baking heater 25.
On the other hand, in the control device 24, temperature management is performed by adjusting the refrigerant flowing through the cooling pipe 51 in the cooling jacket 50 or adjusting the position of the element disposed (arranged) inside.

Next, a cooling method inside the control device 24 in the turbo molecular pump 1 according to the present embodiment will be described.
The control device 24 in the turbo molecular pump 1 according to the present embodiment is provided with the detachable cooling jacket 50 as described above.
For this reason, the internal cooling method in the control device 24 includes two types of cooling methods, a first cooling method when the cooling jacket 50 is mounted and a second cooling method when the cooling jacket 50 is removed. It can be properly used according to the specifications of the pump 1 and the usage environment.

First, the cooling method of the control apparatus 24 by the 1st cooling system with which the cooling jacket 50 was mounted | worn is demonstrated.
FIG. 3 is a diagram showing the flow of air inside the control device 24 when the first cooling method is used.
As shown in FIG. 3, when the operation (air blowing) of the fan 40 is started with the cooling jacket 50 mounted, the air in the control device 24 passes through the heat exchange fins 60 and is provided on the side wall 31 d of the housing 30. It is sent to the communication passage 52 of the cooling jacket 50 through the exhaust hole 32 formed.
Thereafter, the air in the control device 24 is sent from the communication path 52 to the second region inside the housing 30 through the air intake hole 33 provided in the side wall 31 d of the housing 30.
The air in the control device 24 passes between the stacked control boards 70 or between the control board 70 and the lower lid 82, and then is sent to the fan 40 again to circulate inside the control apparatus 24.
That is, between the fins in the heat exchange fin 60, between the communication path 52, between the stacked control boards 70, and between the control board 70 and the lower lid 82, air circulating inside the control device 24 Functions as a flow path.

Next, a heat dissipation method of the control board 70 when using the first cooling method, that is, a heat transfer path of the control board 70 will be described.
In the control board 70 that is in contact with the partition plate 31e on which an element that generates a large amount of heat is mounted, the heat generated from the mounted element is directly transmitted from the control board 70 to the partition plate 31e, and from the partition plate 31e. It is transmitted to the cooling jacket 50, that is, the cooling pipe 51 through the side walls 31 a to 31 d.
On the other hand, in the control board 70 not in contact with the partition plate 31e, the heat generated from the mounted elements is transferred from the control board 70 to the stacked control boards 70 or between the control board 70 and the lower lid 82. It is transmitted to the air passing between them.
As a result, the air passing between the stacked control boards 70 or between the control boards 70 and the lower lid 82 is heated.
When the heated air passes through the heat exchange fins 60 cooled by the cooling action of the cooling jacket 50 (cooling pipe 51), the heat is transferred to the heat exchange fins 60 and is cooled.
Then, the air cooled by the heat exchange fins 60 is sent to the control board 70 again.

Specifically, the temperature of the control board 70 is heated to 70 to 80 ° C. by the heat generated by the mounted elements.
The air circulating inside the control device 24 is heated to about 60 ° C. by absorbing heat from the control board 70 when passing through the arrangement area of the control board 70.
Then, when the heated air passes through the heat exchange fin 60 cooled to about 30 ° C. by the action of the cooling jacket 50 (cooling pipe 51) cooled to about 20 ° C., it is cooled to about 40 ° C. And sent to the control board 70 again.
Here, an example of the temperature of each part is shown, and the temperature state changes depending on the use conditions.

As described above, according to the first cooling method, the heat generated in the control board 70 is transferred not only to the partition plate 31e but also to the cooling jacket 50 (cooling pipe 51) through the air circulating in the control device 24. It can be discharged outside the control device 24.
According to the first cooling method, by forcibly circulating the air in the control device 24, it is possible to suppress the occurrence of a region in which the humidity or temperature is remarkably increased (or decreased) inside the control device 24. . Thereby, overheating and dew condensation inside the control device 24 can be appropriately prevented.
According to the first cooling method, the heat dissipation process can be performed appropriately even with the stacked control boards 70, and therefore the control device 24 can be easily downsized.
By using the first cooling method, the inside of the housing 30 is sealed by the cooling jacket 50, so that the turbo molecular pump 1 is installed even in an environment in which condensation does not occur without contact with outside air. Can do.
Further, in the first cooling method, heat is released to the outside through the cooling pipe 51, so that the periphery of the turbo molecular pump 1 can be prevented from becoming a heat spot. The heat spot indicates a place (spot) where the temperature is locally increased in the room where the turbo molecular pump 1 is installed.

By using the first cooling method, the inside of the housing 30 is hermetically sealed by the cooling jacket 50, so that it is possible to easily take measures against waterproofing inside the control device 24, specifically, the control board 70 (control circuit).
In the above-described embodiment, the cooling jacket 50 provided with the cooling pipe 51 is used to cool the casing 30, the partition plate 31e, and the heat exchange fins 60. However, the casing 30, the partition plate 31e is used. And the cooling method of the heat exchange fin 60 is not limited to this.
For example, the casing 30, the partition plate 31e, and the heat exchange fins 60 may be cooled by bringing the cooling jacket 50 into contact with a low-temperature structure without providing the cooling pipe 51.

Then, the cooling method of the control apparatus 24 by the 2nd cooling system which removed the cooling jacket 50 is demonstrated.
FIG. 4 is a diagram illustrating an air flow inside the control device 24 when the second cooling method is used.
As shown in FIG. 4, when the operation (air blowing) of the fan 40 is started with the cooling jacket 50 removed, the air is supplied to the outside of the control device 24 through the intake hole 33 provided in the side wall 31 d of the housing 30. To the second region inside the housing 30.
The air sucked from the outside passes between the stacked control boards 70 or between the control boards 70 and the lower lid 82 and is sent to the fan 40.
Thereafter, the air in the control device 24 passes through the heat exchange fins 60 and is exhausted (exhausted) to the outside of the control device 24 from the exhaust holes 32 provided in the side wall 31 d of the housing 30.
That is, between the fins in the heat exchange fin 60, between the stacked control boards 70, and between the control board 70 and the lower lid 82, functions as an air flow path that circulates inside the control device 24. To do.

Next, a heat dissipation method of the control board 70 when using the second cooling method, that is, a heat transfer path of the control board 70 will be described.
In the control board 70 that is in contact with the partition plate 31e on which an element that generates a large amount of heat is mounted, the heat generated from the mounted element is directly transmitted from the control board 70 to the partition plate 31e, and from the partition plate 31e. It is transmitted to the heat exchange fin 60.
The heat transferred to the heat exchange fin 60 is transferred to the air passing through the heat exchange fin 60. The heated air is exhausted (exhausted) from the exhaust hole 32 to the outside of the control device 24, so that the heat generated inside the control device 24 is released to the outside.
On the other hand, in the control board 70 not in contact with the partition plate 31e, the heat generated from the mounted elements is transferred from the control board 70 to the stacked control boards 70 or between the control board 70 and the lower lid 82. It is transmitted to the air passing between them.
As a result, the air passing between the stacked control boards 70 or between the control boards 70 and the lower lid 82 is heated.
The heated air passes through the heat exchange fins 60 and is then exhausted (exhausted) from the exhaust hole 32 to the outside of the control device 24, whereby heat generated inside the control device 24 is released to the outside.

Specifically, the temperature of the control board 70 is heated to 70 to 80 ° C. by the heat generated by the mounted elements.
The air taken into the control device 24 at about 30 ° C. is heated to about 40 ° C. by absorbing heat from the control substrate 70 when passing through the arrangement region of the control substrate 70.
Then, when the heated air passes through the heat exchange fins 60 heated to about 60 ° C. by the heat from the control board 70 in contact with the partition plate 31e, the heated air is further heated to about 50 ° C. 24 is discharged to the outside.
Here, an example of the temperature of each part is shown, and the temperature state changes depending on the use conditions.

As described above, according to the second cooling method, the heat generated in the control board 70 and the heat transmitted from the control board 70 to the partition plate 31e are circulated through the circulating air taken into the control apparatus 24. 24 can be discharged to the outside.
In the second cooling method, even if the control board 70 is laminated by using the above-described forced air cooling method, the heat dissipation process can be appropriately performed, so that the control device 24 can be easily downsized.
According to the second cooling method, since the inside of the control device 24 can be cooled without providing the cooling jacket 50 (cooling pipe 51), the cooling system can be constructed at low cost.
In addition, according to the second cooling method, the inside of the control device 24 can be cooled without providing the cooling jacket 50 (cooling pipe 51), that is, since no cooling water supply facility is required, the turbo molecular pump It is possible to reduce restrictions on the installation location of 1.

As described above, according to the present embodiment, the first cooling method and the second cooling method can be easily switched by switching the attachment / detachment of the cooling jacket 50.
Thus, since the cooling method of the control device 24 can be switched in one turbo molecular pump 1, the cooling method of the control device 24 can be switched according to the use environment and specification conditions even after delivery of the product. It can be done easily. Thereby, the expense at the time of the change of a cooling system can be held down.
For example, in an environment where it is difficult to use the water cooling facility, the cooling jacket 50 is removed and the control device 24 is cooled by the second cooling method, that is, only air cooling is performed.
In addition, for example, in a use environment where there is a concern about malfunctions due to heat spots, the cooling jacket 50 is attached to perform cooling of the control device 24 by the first cooling method, that is, cooling using both water cooling and air cooling. .

In the present embodiment described above, air is used as an example of the fluid in the control device 24, but the fluid in the control device 24 is not limited to this.
For example, when the inside of the control device 24 is sealed as in the first cooling method, a liquid cooling method using a liquid insulator may be used as the fluid in the control device 24. In this case, however, a circulation pump is provided instead of the fan 40 in order to circulate the fluid.

Claims (7)

A pump body containing a gas transfer mechanism for transferring gas from the intake port to the exhaust port;
A control device mounted on the pump body, including a control circuit for controlling the pump body, and having a housing sealed inside;
A vacuum pump comprising:
The control device comprises a forced convection generating means for forcibly generating a flow in the fluid in the casing ,
The housing of the control device is
A first housing part having a flow hole communicating with a fluid flow path in the housing on a side surface and containing the control circuit;
A second housing portion disposed so as to cover the flow hole,
The vacuum pump characterized in that the second housing part is detachably attached to the first housing part . The control circuit has a heating element that is heated by self-loss,
The controller is
A heat exchange mechanism for absorbing heat generated in the control circuit;
Cooling means for cooling the heat exchange mechanism;
The vacuum pump according to claim 1, comprising: The heat exchange mechanism, the vacuum pump 請 Motomeko 2 wherein you characterized in that it constitutes a flow path of the housing of the fluid. The control device includes a control board on which the control circuit is mounted and which constitutes a fluid flow path in the housing.
Wherein the heat exchange mechanism is 請 Motomeko 2 or claim 3 pump according you, characterized in that to absorb the heat of the control board. The control board is laminated through a gap,
The vacuum pump according to claim 4, wherein the adjacent control board constitutes a fluid flow path in the casing. The vacuum pump according to any one of claims 2 to 5 , wherein the cooling means is provided in the second casing. The vacuum pump according to any one of claims 1 to 6 , wherein the control device is attached to the pump main body via a heat insulating means.

Images