JP3172822U - Vacuum pump - Google Patents

Abstract

A vacuum pump capable of reducing the cost of a sealing structure between a control unit and a pump body is provided.
An opening provided in a base portion is hermetically sealed using a hermetic circuit board. The hermetic circuit board 20 has inner and outer connection pads 28 and 29 formed on both front and back surfaces of the thin metal plate 20 via insulating layers 22 to 24. The inner / outer connection pads 28 and 29 are connected by a conductive layer 27 formed on the inner surfaces of the through holes 22 a to 24 a and the inner surface of the fourth insulating layer 25 in the via hole 71. The through holes 23a are arranged at positions different from the through holes 22a, 24a and the via holes 71 provided in a straight line in a plan view. Thereby, the internal space of the base part 4 is kept airtight.
[Selection] Figure 4

Description

  The present invention relates to a vacuum pump including a pump body having an exhaust part and a control device for controlling the exhaust part.

  Vacuum pumps such as turbo molecular pumps are attached to semiconductor devices and liquid crystal manufacturing equipment, rotate the built-in rotor at high speed, draw gas molecules from the intake port, exhaust them from the exhaust port, and vacuum the inside of the manufacturing device. To. The vacuum pump includes a pump body having an exhaust part and a control device that controls the exhaust part of the pump body. When the control device is integrated with the pump body, the routing of the cable connected to the driving device such as a motor and the bearing is simplified, and the efficiency of the connection work is improved.

The pump body is often provided with a water-cooled cooling mechanism, and the connector plug mechanism requires a drip-proof mechanism.
As an example, a hermetic seal connector to which motor wiring and control wiring are connected is attached to the pump body, an insulator socket connected to the control circuit section is attached to a panel member fixed to the casing of the control device, and the insulator is attached to the hermetic seal connector. A structure in which a socket is mounted is known (for example, see Patent Document 1).

Utility model registration No. 3138105

  In the device described in Patent Document 1, a connector having an expensive hermetic seal structure is used, and the structure is complicated, so that the cost is high.

  This device is provided with a pump body having an exhaust part for exhausting gas flowing in from an intake port from an exhaust port, a control device for supplying electric power and a control signal to the exhaust part, and a pump body and a control device. A connection structure portion connected through the opening, and a case for sealing the connection structure portion from the outside. The connection structure portion is provided on one surface side of the metal thin plate via an insulating layer, and is connected to the control device. The first pad to which the wiring of the connected first harness is bonded and the wiring of the second harness which is provided on the other surface side of the metal thin plate via an insulating layer and connected to the exhaust part of the pump body are bonded. And a mounting means for attaching the substrate to the peripheral portion of the opening of the pump body in an airtight manner.

  According to this device, since the airtight structure can be obtained by the substrate in which the first pad and the second pad are formed on the front and back surfaces of the thin metal plate via the insulating layer, the cost can be reduced.

1 is an overall schematic configuration diagram showing an embodiment of a vacuum pump according to the present invention. Sectional drawing which shows the detail of the control unit fixed to the base part. FIG. 3 is an exploded perspective view of the control unit illustrated in FIG. 2. FIG. 3 is an enlarged cross-sectional view of the hermetic circuit board illustrated in FIG. 2. The expanded sectional view of the hermetic circuit board as Embodiment 2 of this invention. The expanded sectional view of the hermetic circuit board as Embodiment 3 of this invention.

(Embodiment 1)
Hereinafter, a vacuum pump according to the present invention will be described with reference to the drawings and a turbo molecular pump as an embodiment together with the drawings.
FIG. 1 is a diagram schematically showing the overall configuration of a turbo molecular pump.
The turbo molecular pump 1 includes a pump body 2 and a control unit 3. The pump main body 2 includes a casing 5 in which an exhaust function unit is built in, and a base unit 4 that is attached to the casing 5 in an airtight manner and on which a motor, a sensor, and the like are mounted.
The turbo molecular pump 1 is fixed to an external device 7 such as a semiconductor device manufacturing apparatus via a flange 5 having an intake port provided on the upper side of the pump body 2.

Although not shown, the turbo molecular pump 1 includes, in the pump body 2, a rotor in which rotor blades are provided in multiple stages, a turbine exhaust portion including stator blades disposed between the rotor blades, a lower outer peripheral surface of the rotor, A thread-drag type molecular drag exhaust part constituted by screws and grooves provided on the inner peripheral surface of the base part 4 is provided.
In addition, in the casing 5 and the base portion 4, a motor for rotating the rotor shaft mounted coaxially with the rotor, a plurality of magnetic bearings floating on the rotor shaft, and displacements in the radial and axial directions of the rotor shaft are detected. A displacement sensor is installed.

  The turbo molecular pump 1 sucks gas molecules from the external device 7 by the action of the exhaust function unit, and exhausts the gas molecules from the exhaust port 6 through the turbine exhaust unit and the molecular drag exhaust unit. The turbo molecular pump 1 provided with the turbine exhaust part and the molecular drag exhaust part can make the external device 7 high vacuum, and the gas molecules discharged from the exhaust port 6 are transferred to the back pump which is a low vacuum device. Be transported.

  Although not shown, the base portion 4 includes a water-cooled cooling jacket. A control unit (control device) 3 is attached to the outer periphery of the base portion 4. The control unit 3 includes a motor, a magnetic bearing, and the like mounted in the base portion 4 through an opening provided in the base portion 4. It is electrically connected to a displacement sensor or the like.

FIG. 2 is a cross-sectional view showing details of the control unit 3 fixed to the base portion 4, and FIG. 3 is an exploded perspective view of the control unit 3. However, in FIG. 3, the control circuit board assembly 30 and the fastening member shown in FIG. 2 are not shown.
The base part 4 has a cylindrical shape or a polygonal cylindrical shape such as a hexagon or an octagon, and a circular opening 4a that opens from the inside to the outside is provided on the outer peripheral side surface. The hermetic circuit board (substrate) 20 is attached so as to seal the space in the base part 4 from the outside by closing the opening 4a.

  That is, a large-diameter portion 4a1 is formed on the outer peripheral side of the opening 4a, and a sealing member 51 is fitted into the large-diameter portion 4a1. The hermetic circuit board 20 is provided with a plurality of through holes 26, and fastening members 61 (see FIG. 2) such as screws inserted through the through holes 26 are fastened to the female screw portions 41 provided in the base portion 4. Has been. In this state, one surface of the hermetic circuit board 20 is pressed against the sealing member 51, and the inside of the base portion 4 is kept airtight from the outside.

The inner harness 10 connected to the constituent elements or connection terminals of the exhaust function unit mounted in the base unit 4 is connected to the surface of the hermetic circuit board 20 on the base unit 4 side.
The periphery of the hermetic circuit board 20 is covered with a cylindrical case 55 attached to the base portion 4. That is, a circular annular groove 4b is provided on the outer periphery of the opening 4a of the base portion 4, and a sealing member 52 is fitted into the annular groove 4b. A plurality of through holes 53 are provided in the flange 55 a of the case 55, and a fastening member 62 (see FIG. 2) such as a screw that passes through the through holes 53 is fastened to the female screw portion 42 provided in the base portion 4. Has been. In this state, the flange 55a is pressed against the sealing member 52, and the inside of the case 55 is kept airtight from the outside.

  In a case 55 attached to the outer peripheral side surface of the base portion 4, a control signal circuit board 33, a power supply circuit board 34, and a holding member 36 that holds the circuit boards 33 and 34 are provided. The circuit board assembly 30 is accommodated. The power supply circuit board 34 includes an AC / DC converter circuit and an inverter / motor drive circuit, and includes a circuit for supplying drive power to the motor. Further, a circuit for supplying power for power supply to the control signal circuit board 33 is provided. The control signal circuit board 33 includes a magnetic bearing drive circuit and a displacement sensor control / detection circuit, and includes a circuit for controlling the entire vacuum pump.

The surface of the hermetic circuit board 20 opposite to the base side is connected to the outer harness 80. The outer harness 80 is connected to the control signal circuit board 33 and the power supply circuit via connectors 31 and 32, respectively. It is connected to the substrate 34.
Next, the structure of the hermetic circuit board 20 and the connection between the hermetic circuit board 20 and the inner and outer harnesses 10 and 80 will be described in more detail.

FIG. 4 is an enlarged sectional view showing the hermetic circuit board 20 and the hermetic structure.
The hermetic circuit board 20 has a metal thin plate 21 made of copper or aluminum as a base member. A first insulating layer 22 and a second insulating layer 23 are formed on one surface of the metal thin plate 21 on the base portion 4 side. On the other surface of the metal thin plate 21, a third insulating layer 24 is formed. A via hole 71 penetrating from one surface to the other surface is formed in the metal thin plate 21, and a fourth insulating layer 25 that covers the metal thin plate 21 at the periphery of the via hole 71 is formed on the inner surface of the via hole 71. .

The hermetic circuit substrate 20 is formed with a conductive layer 27 extending from one surface to the other surface via the fourth insulating layer 25 in the via hole 71. The conductive layer 27 has a plurality of inner connection pads 28 formed on the second insulating layer 23 and a plurality of outer connection pads 29 formed on the third insulating layer 24.
Each inner connection pad 28 is arranged on the hermetic circuit board 20 corresponding to each of the wires bundled as the inner harness 10 (see FIG. 3). Although not shown, each outer connection pad 29 is arranged on the hermetic circuit board 20 corresponding to each of the wires bundled as the outer harness 80. The total number of wires connecting the control unit 3 and the pump body 2 is usually 10-50.

  Through holes 22a, 23a, and 24a are formed in the first to third insulating layers 22, 23, and 24, respectively. The conductive layer 27 is formed of the through holes 23a to 24a and the fourth insulating layer 25. It is provided on the inner surface. Each conductive layer 27 extends from the inner connection pad 28 through the through hole 23 a formed in the second insulating layer 23 onto the first insulating layer 22, and the through hole 22 a of the first insulating layer 22. The via hole 71 is routed to the outer connection pad 29 through the inner surface of the fourth insulating layer 25 and the through hole 24 a of the third insulating layer 24. The through holes 22a, 24a and the via hole 71 are formed in a straight line and communicate with each other, and the through hole 23a is arranged at a position different from the through holes 22a, 24a and the via hole 71 provided in a straight line. ing. For this reason, one end of the through hole 23 a is closed by the first insulating layer 22.

  The thickness of the thin metal plate 21 is about 0.5 to 1.0 mm, the thickness of the inner / outer connection pads 28 and 29 is about 70 μm, and the inner routing routed on the first insulating layer 22 in the conductive layer 27. The thickness of the part is about 35 μm. The thickness of each insulating layer 22-24 is adjusted so that the thickness of the entire hermetic circuit board 20 is about 1.0 to 2.0 mm. However, the thickness of each member described above is an example, and is not limited thereto.

Each inner connection pad 28 is connected to a corresponding wiring of the inner harness 10 by soldering or the like. Similarly, each outer connection pad 29 is bonded to a corresponding wiring of the outer harness 80 by soldering or the like. ing.
The hermetic circuit board 20 includes a sealing conductive layer 60 formed in an annular shape on the second insulating layer 23 in which the inner connection pads 28 are arranged. The sealing conductive layer 60 has a diameter corresponding to the sealing member 51, and the sealing member 51 is disposed on the sealing conductive layer 60. The sealing conductive layer 60 is formed of the same material in the same process as the inner connection pad 28.

That is, the sealing member 51 is disposed in the large diameter portion 4 a 1 in the opening 4 a of the base portion 4, and is in pressure contact with the sealing conductive layer 60 by fastening of the fastening member 61.
In this state, one end portion of the through hole 23a opened from the second insulating layer 23 to the space of the base portion 4 is closed by the first insulating layer 22 and the metal thin plate 21, so that the base portion 4 side The inner space is sealed with respect to the space in the case 55. That is, the internal space of the pump body 2 is airtightly held by the hermetic circuit board 20 and the sealing member 51.

Thus, in one embodiment of the present invention, the hermetic circuit board 20 and the sealing member 51 isolate the pump body 2 and the control unit 3 from each other in a sealed state, so that the airtightness of the pump body 2 is maintained. It has become. This structure does not require an expensive hermetic seal connector or the like, and has a simple structure with a small number of parts, so that the cost can be reduced.
In this case, since the hermetic circuit board 20 is formed with the annular sealing conductive layer 60, airtightness can be easily and reliably ensured.

(Embodiment 2)
FIG. 5 is an enlarged cross-sectional view of a hermetic circuit board 20A as Embodiment 2 of the present invention.
In the second embodiment, the point that the hermetic circuit board 20A is different from the hermetic circuit board 20 in the first embodiment will be described, and with respect to common matters, corresponding members are denoted by the same reference numerals and description thereof is omitted. To do.
The hermetic circuit board 20A is not provided with the sealing conductive layer 60.
The sealing member 51 is in direct pressure contact with the second insulating layer 23 of the hermetic circuit board 20A. Thus, even when the hermetic circuit board 20A on which the sealing conductive layer 60 is not formed is used, the same effects as those of the first embodiment are obtained.

(Embodiment 3)
FIG. 6 is an enlarged cross-sectional view of a hermetic circuit board 20B as Embodiment 3 of the present invention.
In the third embodiment, the point that the hermetic circuit board 20B is different from the hermetic circuit board 20 in the first embodiment will be described, and the common items are denoted by the same reference numerals and the description thereof is omitted. To do.
The hermetic circuit board 20B has a first insulating layer 22 and a second insulating layer 23 on the surface opposite to the base portion 4 of the thin metal plate 21, and a third insulating layer 24 on the surface on the base portion 4 side. Have. On the third insulating layer 24, a plurality of inner connection pads 28 are arranged, and an annular sealing conductive layer 60 surrounding the inner connection pads 28 is formed. The sealing conductive layer 60 is formed of the same material in the same process as the inner connection pad 28. As in the case of the first embodiment, the sealing member 51 is in pressure contact with the sealing conductive layer 60.

On the second insulating layer 23, a plurality of outer connection pads 29 are arranged.
Each conductive layer 27 includes a through hole 24 a formed in the third insulating layer 24 from the inner connection pad 28, an inner surface of the fourth insulating layer 25 in the via hole 71, and a through hole formed in the first insulating layer 22. It extends on the first insulating layer 22 through 22 a and is routed to the outer connection pad 29 through the through hole 23 a of the second insulating layer 23.
In the hermetic circuit board 20B, the through hole 24a, the via hole 71, and the through hole 22a are formed in a straight line and communicated with each other. One end of the connected hole is closed by the second insulating layer 23.
Therefore, even with such a hermetic circuit board 20B, the airtightness of the space of the base portion 4 is ensured, and the same effect as in the first embodiment can be obtained.
Also in the third embodiment, a structure without the sealing conductive layer 60 can be provided.

  As described above, in each embodiment of the present invention, the control unit 3 is attached to the base portion 4 while ensuring the airtightness of the base portion 4 with a simple configuration of the hermetic circuit boards 20, 20 </ b> A, 20 </ b> B and the sealing member 51. It can be attached and the cost can be reduced.

  In the above embodiments, the control unit 3 is illustrated as being attached to the outer peripheral side surface of the base portion 4. However, the present invention can also be applied to the case where the control unit 3 is attached to the bottom portion of the base portion 4. When the control unit 3 is attached to the base part, the area of the opening 4a for communication with the control unit 3 provided at the bottom part of the base part 4 is significantly smaller than the area of the bottom part of the base part 4, Strength can be secured and cost can be reduced.

  The number of control circuit board assemblies 30 accommodated in the control unit 3, the connection means, the structure, and the like are not limited to the illustrated modes.

  In the above description, the turbo molecular pump has been described as an embodiment. However, the present invention can be applied to other vacuum pumps.

  The shape of the case 55 and the sealing structure for attaching the case 55 to the base portion 4 are not limited to the aspects of the embodiment. In particular, when the pump is not cooled by water, the sealing structure can be a simple structure.

  In addition, the present invention can be applied with various modifications within the scope of the idea. In short, in the structure in which the control device is attached to the pump body, the opening provided in the pump body is made of a metal thin plate. Any material that is hermetically sealed by a hermetic circuit board having a plurality of connection pads formed on both front and back surfaces via an insulating layer may be used.

DESCRIPTION OF SYMBOLS 1 Turbo molecular pump 2 Pump main body 3 Control unit 4 Base part 4a Opening part 10 Inner harness 20, 20A, 20B Hermetic circuit board 21 Metal thin plate 22-24 Insulating layer 22a, 23a, 24a Through hole 27 Conductive layer 28 Inner connection pad 29 Outer connection pad 30 Control circuit board assembly 51, 52 Sealing member 55 Case 60 Sealing conductive layer 71 Via hole 80 Outer harness

Claims (6)

A pump body provided with an exhaust part for discharging the gas flowing in from the intake port through the exhaust port;
A control device for supplying electric power and a control signal to the exhaust unit;
A connection structure for connecting the pump body and the control device through an opening provided in the pump body;
A case for sealing the connection structure portion from the outside,
The connection structure is
A first pad, which is provided on one surface side of the metal thin plate via an insulating layer and bonded to the wiring of the first harness connected to the control device, and an insulating layer on the other surface side of the metal thin plate A substrate having a second pad to which a wiring of a second harness connected and connected to the exhaust part of the pump body is bonded;
A vacuum pump comprising: attachment means for airtightly attaching the substrate to a peripheral portion of the opening of the pump body.   2. The vacuum pump according to claim 1, wherein the substrate is provided so as to penetrate the metal thin plate and the insulating layer provided on both surfaces of the metal thin plate and connect the first and second pads. A vacuum pump comprising a hole, wherein the through hole has a portion penetrating the thin metal plate and a portion penetrating one of the insulating layers at different positions in plan view.   3. The vacuum pump according to claim 1, wherein the attachment means includes a sealing member disposed in an annular shape along a peripheral edge of the opening of the pump body, and one surface of the substrate corresponding to the sealing member. A vacuum pump comprising a metal foil provided in an annular shape on the side.   4. The vacuum pump according to claim 3, wherein the metal foil is made of the same material as the first and second pads.   5. The vacuum pump according to claim 1, wherein a thickness of the metal thin plate is thicker than that of the first pad and the second pad. 6. 6. The vacuum pump according to claim 1, wherein the thickness of the substrate is 1 to 2 mm.

Images