Patent Grant
11415151
This application is a Section 371 National Stage Application of International Application No. PCT/JP2019/004744, filed Feb. 8, 2019, which is incorporated by reference in its entirety and published as WO 2019/159854 A1 on Aug. 22, 2019 and which claims priority of Japanese Application No. 2018-0:25853, filed Feb. 16, 2019.
The present invention relates to a vacuum pump such as a turbomolecular pump, and a control device of the vacuum pump.
The turbomolecular pump device disclosed in, for example, WO 2011/111209, has conventionally been known. The turbomolecular pump device of WO 2011/111209 is provided with cooling devices 13 as described in paragraph 0010 and shown in FIGS. 1, 2, and the like. The cooling devices 13 are interposed side by side in the axial direction between a pump main body 11 and a power supply apparatus 14, and cool mainly electronic components of a motor drive circuit in the power supply apparatus 14. The cooling devices 13 each have a jacket main body 13a in which a cooling water passage is formed, and a cooling water inlet 13b and a cooling water outlet 13c for circulating cooling water in the cooling water passage by means of a water-feeding pump.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background.
Incidentally, vacuum pumps such as turbomolecular pumps need to be downsized for reasons such as the surrounding space of the vacuum equipment to be connected. In some cases, electrical equipment such as motor drive circuits and control circuits need to be downsized as well, and in such a case, the mounting density of the electrical equipment increases easily, thereby raising the temperatures of the electrical equipment. The mounting density of the electrical equipment is increased also by improved performance of the vacuum pump, thereby easily increasing the temperatures of the electrical equipment. For this reason, even when the cooling devices disclosed in, for example, WO 2011/111209 are used, cooling needs to be performed as efficient as possible. Efficient cooling can extend the life of the electrical equipment. Further, although the water-cooling type cooling device is suitable for cooling a limited area such as a part that is in contact with or faces the cooling device, it is difficult to cool an area larger than the outer shape of the cooling device.
In order to enhance the cooling effect, air cooling using, for example, a cooling fan in place of the water cooling described in WO 2011/111209 is considered. However, the external dimensions of the vacuum pump increase by providing the cooling fan, making downsizing of the vacuum pump difficult. Moreover, use of the cooling fan causes the generated air flow to raise dust in the clean room, making it difficult to maintain the clean environment. In addition, when the cooling fan is used, intensive use of an air conditioner to eliminate the raised dust may result in an increase of the total energy consumption. For these reasons, it is difficult to employ air cooling to achieve efficient cooling in a vacuum pump such as a turbomolecular pump; thus, it is desired that water cooling be employed.
The present invention was contrived in order to solve the foregoing problems, and an object thereof is to provide a vacuum pump capable of efficiently cooling electrical equipment, and a control device of the vacuum pump.
In order to achieve the object described above, the present invention provides a vacuum pump comprising a pump main body, and a control device disposed outside the pump main body, wherein the control device includes a cooling portion which has a cooling surface and in which a cooling medium flow passage is formed, and a plurality of electrical component portions that each have a heat generating component and is capable of being by the cooling portion, a plurality of the cooling surfaces are formed facing different directions, and the plurality of electrical component portions are attached to the plurality of cooling surfaces respectively so that heat can be transferred.
In order to achieve the object described above, the present invention according to another aspect is a vacuum pump, wherein the plurality of electrical component portions have a circuit board that has the heat generating components mounted thereon and is fixed to the cooling surface, and at least one of the plurality of electrical component portions is provided with a mold portion that covers the circuit board and the heat generating components at least partially.
In order to achieve the object described above, the present invention according to another aspect is a vacuum pump, wherein the control device is divided into a plurality of housing spaces by the cooling portion, and each of the housing spaces includes at least one of the plurality of electrical component portions.
In order to achieve the object described above, the present invention according to another aspect provides a control device of a vacuum pump, comprising a cooling portion which has a cooling surface and in which a cooling medium flow passage is formed; and a plurality of electrical component portions that each have a heat generating component and can be cooled by the cooling portion, wherein a plurality of the cooling surfaces are formed facing different directions, and the plurality of electrical component portions are attached to the plurality of cooling surfaces respectively so that heat can be transferred.
The present invention can provide a vacuum pump capable of efficiently cooling electrical equipment, and a control device of the vacuum pump.
The Summary is provided to introduce a selection of concepts in a simplified form that are further described in the Detail Description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
A vacuum pump according to one embodiment of the present invention is now described hereinafter with reference to the drawings.
The turbomolecular pump 10 integrally has a cylindrical pump main body 11 and a box-shaped electrical equipment case 31 as an electrical equipment storage (control device). The pump main body 11 has an inlet portion 1:2 on the upper side in the drawing which is connected to a side of the target device, and an exhaust portion 13 on the lower side which is connected to an auxiliary pump or the like. The turbomolecular pump 10 can be used not only in a vertical posture in the vertical direction as shown in
The electrical equipment case 31 is attached to an outer peripheral surface, which is a side portion of the pump main body 11, in such a manner as to protrude in a radial direction. Thus, the turbomolecular pump 10 of the present embodiment is downsized in the axial direction as compared to the type disclosed in, for example, WO 2011/111209 in which the pump main body and the electrical equipment (electrical component) are arranged in the axial direction (gas transfer direction). Furthermore, the turbomolecular pump 10 of the present embodiment can be installed even if an axial space is relatively narrow.
The pump main body 11 has a cylindrical main body casing 14 with steps. In the present embodiment, the main body casing 14 has a diameter of approximately 350 mm and a height of approximately 400 mm. The inside of the main body casing 14 is provided with an exhaust mechanism portion 15 and a rotary drive portion 16. The exhaust mechanism portion 15 is of a composite type composed of a turbomolecular pump mechanism portion 17 and a thread groove pump mechanism portion 18.
The turbomolecular pump mechanism portion 17 and the thread groove pump mechanism portion 18 are disposed in a continuous fashion in the axial direction of the pump main body 11; in
The turbomolecular pump mechanism portion 17 disposed on the upper side in
The stator blade portion 19 is provided integrally on the main body casing 14, and the rotor blades provided in the rotor blade portion 20 are each sandwiched between upper and lower stator blades provided in the stator blade portion 19. The rotor blade portion 20 is integrated with a rotating shaft (rotor shaft) 21, only an upper end of which is schematically shown in
The rotating shaft 21 passes through the thread groove pump mechanism portion 18 on the lower side and is coupled to the abovementioned rotary drive portion 16, only the outline of which is schematically shown in the drawing. The thread groove pump mechanism portion 18 includes a rotor cylindrical portion 23 and a thread stator 24, wherein a thread groove portion 25, which is a predetermined gap, is formed between the rotor cylindrical portion 23 and the thread stator 24. The rotor cylindrical portion 23 is coupled to the rotating shaft 21 so as to be able to rotate integrally with the rotating shaft 21. An outlet port 26 to be connected to an exhaust pipe is disposed below the thread groove pump mechanism portion 18, whereby the inside of the outlet port 26 and the thread groove portion 25 are spatially connected.
The rotary drive portion 16 is a motor and includes, although not shown, a rotor formed on an outer periphery of the rotating shaft 21 and a stator disposed so as to surround the rotor. The power for activating the rotary drive portion 16 is supplied by power supply equipment or control equipment stored in the electrical equipment case 31 described above.
Although not shown, a non-contact type bearing by magnetic levitation (magnetic bearing) is used to support the rotating shaft 21. Therefore, the pump main body 11 can realize an environment in which the pump is not worn when rotated at high speed, has a long life, and does not require lubricating oil. A combination of a radial magnetic bearing and a thrust hearing can be employed as the magnetic bearing. Further, the magnetic bearing can be used in combination with a touchdown bearing to prevent possible damage.
Driving the rotary drive portion 16 rotates the rotor blade portion 20 and the rotor cylindrical portion 23 of the turbomolecular pump mechanism portion 17 that are integrated with the rotating shaft 21. When the rotor blade portion 20 is rotated, the gas is drawn from the inlet portion 12 shown on the upper side of
The electrical equipment case 31 is described next. As shown in
The cooling jacket 36 includes a jacket main body 37 and a cooling pipe 38. Among them, the jacket main body 37 is a casting having a T-shaped cross section, where the casting integrally includes a first horizontal portion 39a and a second horizontal portion 39b that are oriented substantially horizontally and a vertical portion 40 oriented substantially vertically. Aluminum or the like can be employed as the material (casting material) of the cooling jacket 36. The first horizontal portion 39a has a base end side thereof connected to the vertical portion 40 and facing outside the pump main body 11 and extends a tip end side in the direction toward the main body casing 14. The second horizontal portion 39h has a base end side thereof connected to the vertical portion 40 and facing the main body casing 14 and has a tip end side thereof facing outside the pump main body 11.
Furthermore, as shown in
As shown in
Here, as shown in
As shown in
The cooling pipe 38 is bent into a C-shape in the vertical portion 40, and includes parallel portions 50 extending substantially horizontally and parallel to each other, and a vertical connecting portion 51 connecting the parallel portions 50. In the present embodiment, of the both ends 52, 53 of the cooling pipe 38, the end 53 on the lower side in
The cooling portion is generally cooled h the cooling water flowing through the cooling pipe 38. However, the cooling medium (refrigerant) is not limited to the cooling water; a fluid other than water or other cooling medium such as a cold gas may be used.
Next, the power supply circuit portion 33 is described on the basis of
Examples of the circuit components 62 include transformers, coils, capacitors, filters, diodes, field effect transistors (FETs), and the like.
Here, when mounting various circuit components 62 onto the circuit board 61, the directions (or “postures”) of the circuit components 62 are determined in view of the heights thereof. In other words, although the cooling jacket 36 is positioned on the back side of the circuit board 61 (the non-mounting side) as described above, the circuit components 62 become far away from the cooling jacket 36 as the heights of the circuit components 62 increase on the mounting side of the circuit board 61. Mounting the circuit components 62 having large heights (i.e., tall circuit components 62) upright makes it difficult to transfer heat to the cooling jacket 36 by heat conduction or heat transmission, and as a result the power supply circuit portion 33 cannot be cooled easily.
Therefore, in the present embodiment, the circuit components 62 are laid out on the circuit board 61, at sections where a necessary area can be secured. In such a state in which the circuit components 62 are laid out, the heights thereof from the circuit board 61 can be reduced, and this state can be referred to as “tilted state” or the like. By laying the circuit components 62 so that a larger portion of the circuit components 62 comes close to the cooling jacket 36, the circuit components 62 can be cooled efficiently.
Furthermore, a plurality of sheet metal members 71 made of metal are mounted on the circuit board 61. The sheet metal members 71 can be fixed by providing the circuit board 61 with a member for supporting the sheet metal members 71 or by providing the sheet metal members 71 with ribs for screwing the sheet metal members 71. Aluminum or the like, for example, is used as the material of the sheet metal members 71.
The sheet metal members 71 may be in a flat shape or an L-shape and are fixed to the circuit board 61 so as to stand upright substantially perpendicularly from the circuit hoard 61 (in an upright posture). The sheet metal members 71 have the thickness direction thereof oriented in a direction in which a mounting surface of the circuit board 61 extends (a direction perpendicular to the thickness direction of the circuit board 61). Mounting the sheet metal members 71 in this orientation can minimize the area occupied by the sheet metal members 71 on the mounting surface of the circuit board 61.
In addition, the sheet metal members 71 can be used for mounting the circuit components 62. Of the various circuit components 62, diodes and other semiconductor elements that tend to increase in temperature are fixed to plate surfaces of the sheet metal members 71. Conduction of the semiconductor elements can be ensured by connecting lead portions (not shown) of the semiconductor elements fixed to the sheet metal members 71 to wiring of the circuit board 61. Providing the circuit components 62 on the plate surfaces of the sheet metal members 71 in this manner can increase the area on the circuit board 61 on which the circuit components 62 can be mounted.
Also, the circuit board 61 is sealed with the mold resin 74 as described above. As shown in
The mold resin 74 is configured to fulfill the function of improving the insulation with respect to the circuit hoard 6L the drip-proof function, the waterproof function, and the like. The mold resin 74 also functions to cool the power supply circuit portion 33 by coming into contact with the various circuit components and the circuit board 61. Specifically, the mold resin 74 removes the heat from the various circuit components and the circuit board 61 and transfers the removed heat to the rear surface side of the circuit board 61.
The control circuit portion 34 is described next. The control circuit portion 34 is for controlling the motor drive mechanism and magnetic bearings provided in the pump main body 11. As shown in
Further, the control circuit portion 34 of the present embodiment has a two-layer laminate structure and includes a metal substrate (aluminum substrate) 86 bolted to the cooling jacket 36, and a resin substrate (glass epoxy substrate or the like) 87 conductively connected to the metal substrate 86. Although not shown, in addition to circuit components 88, connectors and the like in accordance with various standards are mounted on, for example, the resin substrate 87.
In the present embodiment, since the control circuit portion 34 generates less heat compared with the power supply circuit portion 33, resin sealing as in the power supply circuit portion 33 is not performed on the control circuit portion 34. However, if necessary, the control circuit portion 34 may be resin-sealed except for connection terminals of the connectors.
The heat generated by the control circuit portion 34 is transferred not only from the metal substrate 86 joined to the outer surface 47 of the vertical portion 40, but also from a part that is not in direct contact with the vertical portion 40 (such as the resin substrate 87), to the vertical portion 40 via the metal substrate 86 or the space inside of the second housing space 31b.
According to the turbomolecular pump 10 of the present embodiment described above, the first housing space 31a and the second housing space 31b that are divided by the vertical portion 40 of the cooling jacket 36 are formed in the electrical equipment case 31. In the cooling jacket 36, the electrical equipment such as the power supply circuit portion 33 and the control circuit portion 34 are attached to the inner surface 46 and the outer surface 47 of the vertical portion 40, respectively.
Therefore, the electrical equipment (33, 34) can be cooled by recovering the heat of the electrical equipment (33, 34) using the two cooling surfaces (the inner surface 46 and the outer surface 47) facing different directions. Thus, the area that can be cooled by the cooling jacket 36 can be enlarged, thereby cooling more electrical equipment. Therefore, efficient cooling can be achieved without using a cooling fan.
Since a cooling fan is not used, the turbomolecular pump 10 can be downsized. Moreover, not only is it possible to suppress an increase in temperature of the electrical equipment case 31, but also the product life of the turbomolecular pump 10 can be increased. Since efficient cooling can be achieved, the temperature of the cooling water does not need to be lowered much in the preceding stage of the turbomolecular pump 10.
In addition, in the present embodiment, since the electrical equipment (33, 34) are cooled by the inner surface 46 and the outer surface 47 that configure the front and back of the vertical portion 40, cooling of a plurality of surfaces can be realized by simply disposing the cooling pipe 38 in one plane. Also, a wide area can be cooled without laying the cooling pipe 38 in a three-dimensionally complicated shape. Thus, a plurality of cooling surfaces can be formed without complicating the method of bending the cooling pipe 38.
Note that the present invention does not limit the shape of the cooling pipe 38 to the C-shape described in the foregoing embodiment; for example, the cooling pipe 38 can be formed into the shape of an alphabet such as N or M, or into other geometric shapes. Furthermore, the cooling pipe 38 does not have to be formed flat and therefore may be bent three-dimensionally. By forming the cooling pipe 38 into a three-dimensional shape and, for example, by increasing the thickness of the vertical portion 40 or making the vertical portion 40 multifaceted, three or more cooling surfaces can be formed.
According to the turbomolecular pump 10 of the present embodiment, the electrical equipment (33, 34) can be arranged on two surfaces, and, compared to the case where the power supply circuit portion 33 and the control circuit portion 34 are attached integrally to one surface, the length of the vertical portion 40 (the length in the vertical direction in
Since the cooling pipe 38 is incorporated in the cooling jacket 36 by means of casting, an outer peripheral surface of the cooling pipe 38 and the jacket main body 37 can be brought into close contact with each other at low cost. Specifically, in a case where, for example, the jacket main body 37 is produced by scraping an aluminum material and then the cooling pipe 38 is fixed to this produced jacket main body 37, a gap is likely to be created between the jacket main body 37 and the cooling pipe 38, increasing the thermal resistance. In order to perform efficient cooling, a sheet or the like made of a material having high thermal conductivity needs to be interposed between the jacket main body 37 and the cooling pipe 38 to fill the gap, which results in a cost increase. However, by incorporating the cooling pipe 38 by means of casting as described in the present embodiment, the outer peripheral surface of the cooling pipe 38 and the jacket main body 37 can be brought into close contact with each other at low cost.
According to the turbomolecular pump 10 of the present embodiment, since the power supply circuit portion 33 is sealed with the mold resin 74, heat transfer through the mold resin 74 can be achieved. In addition, since the rear surface of the circuit board 61 faces the vertical portion 40 of the cooling jacket 36, the heat generated on the mounting surface of the circuit board 61 can be transferred toward the cooling jacket 36 via the mold resin 74.
In the present embodiment, the mold resin 74 is placed between the circuit board 61 and the cooling jacket 36. Therefore, the heat between the circuit board 61 and the cooling jacket 36 can be transferred via the mold resin 74. For this reason, the heat can be transferred easily as compared with the case where space is provided between the circuit board 61 and the cooling jacket 36.
Note that cooling using the mold resin 74 can further enhance the effect of the cooling by the cooling jacket 36. Also, the cooling described in the present embodiment can be a cooling technique that combines the heat transfer by the mold resin 74 and the cooling by means of the cooling jacket 36. In addition, the cooling described in the present embodiment can be a cooling technique that combines air cooling and water cooling, since the space inside the electrical equipment case 31 is cooled as well by the cooling jacket 36.
The present invention can be modified in various ways in addition to the modes described above.
Although elements have been shown or described as separate embodiments above, portions of each embodiment may be combined with all or part of other embodiments described above.
Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are described as example forms of implementing the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| JP2018-025853 | Feb 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/004744 | 2/8/2019 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2019/159854 | 8/22/2019 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 5971725 | de Simon | Oct 1999 | A |
| 6755611 | Kabasawa | Jun 2004 | B1 |
| 7106595 | Foster, Sr. | Sep 2006 | B2 |
| 7393228 | Kabasawa | Jul 2008 | B2 |
| 7572096 | Nonaka | Aug 2009 | B2 |
| 7753661 | Okudera | Jul 2010 | B2 |
| 7755897 | Chen | Jul 2010 | B2 |
| 7957134 | Farnsworth | Jun 2011 | B2 |
| 7993113 | Namiki | Aug 2011 | B2 |
| 8366380 | Sakaguchi | Feb 2013 | B2 |
| 8651838 | Birkenstock | Feb 2014 | B2 |
| 8690525 | Ohtachi | Apr 2014 | B2 |
| 8961105 | Kogame | Feb 2015 | B2 |
| 9245820 | Goldrian | Jan 2016 | B2 |
| 9267392 | Schroder | Feb 2016 | B2 |
| 9534506 | Okudera | Jan 2017 | B2 |
| 9964112 | Yamato | May 2018 | B2 |
| 10001126 | Miwata | Jun 2018 | B2 |
| 10233943 | Moriyama | Mar 2019 | B2 |
| 10760578 | Shiba | Sep 2020 | B2 |
| 20050276021 | Gates | Dec 2005 | A1 |
| 20070201208 | Goodwin | Aug 2007 | A1 |
| 20130189090 | Okudera | Jul 2013 | A1 |
| 20160195098 | Omori | Jul 2016 | A1 |
| 20180254685 | Seki | Sep 2018 | A1 |
| 20190242386 | Shimizu | Aug 2019 | A1 |
| 20190277296 | Okada | Sep 2019 | A1 |
| 20210025407 | Sun | Jan 2021 | A1 |
| Number | Date | Country |
|---|---|---|
| 102007028475 | Sep 2008 | DE |
| 3754203 | Dec 2020 | EP |
| S642397 | Jan 1989 | JP |
| S645045 | Jan 1989 | JP |
| H07194139 | Jul 1995 | JP |
| 2008244062 | Oct 2008 | JP |
| 2010079397 | Apr 2010 | JP |
| 2013100760 | May 2013 | JP |
| 2014043827 | Mar 2014 | JP |
| 2015049443 | Mar 2015 | JP |
| 2017153339 | Aug 2017 | JP |
| 2017200314 | Nov 2017 | JP |
| 2011111209 | Sep 2011 | WO |
| 2012053271 | Apr 2012 | WO |
| 2019159855 | Aug 2019 | WO |
| Entry |
|---|
| PCT International Search Report dated May 21, 2019 for corresponding PCT Application No. PCT/JP2019/004744. |
| PCT International Written Opinion dated May 21, 2019 for corresponding PCT Application No. PCT/JP2019/004744. |
| PCT International Search Report dated May 21, 2019 for corresponding PCT Application No. PCT/JP2019/004745. |
| PCT International Written Opinion dated May 21, 2019 for corresponding PCT Application No. PCT/JP2019/004745. |
| European Communication dated Oct. 11, 2021 and Search Report dated Oct. 1, 2021 for corresponding European application Serial No. 19753700.4, 8 pages. |
| Number | Date | Country | |
|---|---|---|---|
| 20210025406 A1 | Jan 2021 | US |
