CN-116420028-B - Vacuum pump

Abstract

The invention provides a vacuum pump with excellent exhaust performance. The vacuum pump is provided with a Siemens type exhaust mechanism part (201) provided with a Siemens vortex groove part (262) on at least one of a rotary circular plate (220 a-220 c) and a fixed circular plate (219 a, 219 b), a Hall Wick type exhaust mechanism part (301) provided with a screw groove (131 a) on at least one of a cylinder part (102 d) of a rotary body (103) and a screw spacer (131), wherein the Hall Wick type exhaust mechanism part (301) is arranged at the downstream side of the Siemens type exhaust mechanism part (201), and the vacuum pump is characterized in that the flow path depth of the Hall Wick type exhaust mechanism part (301) is continuously constant at a predetermined depth (H2), and the Siemens type exhaust mechanism part (201) has a region continuously constant at the predetermined depth (H2) from the predetermined position.

Inventors

• HARUKI OSAMU

Assignees

• 埃地沃兹日本有限公司

Dates

Publication Date

20260505

Application Date

20211029

Priority Date

20201104

Claims (2)

1. 1. A vacuum pump comprising a Siegesbeck exhaust mechanism having a swirl groove provided in at least one of a rotary disk and a stationary disk, and a Howeck exhaust mechanism having a spiral groove provided in at least one of a rotary cylinder and a stationary cylinder, the Howeck exhaust mechanism being disposed downstream of the Siegesbeck exhaust mechanism, The Howeck exhaust mechanism has a flow path depth that is continuously constant at a predetermined depth, and the Siegesbeck exhaust mechanism has a region that is continuously constant at the predetermined depth from a predetermined position, Comprises a plurality of layers of the Siegesba exhaust mechanism, The flow path depth of at least the lowest layer of the siegesbam exhaust mechanism connected to the holweck exhaust mechanism among the plurality of siegbam exhaust mechanisms is continuously constant at the predetermined depth.
2. 2. The vacuum pump according to claim 1, wherein, The upstream side of the SiGeoban exhaust mechanism is provided with a rotary wing and a fixed wing, The aforementioned rotary wing has a wing array, The fixed wing is disposed at a predetermined interval from the rotary wing in the axial direction.

Description

Vacuum pump Technical Field The present invention relates to a vacuum pump such as a turbo molecular pump. Background In general, a turbo molecular pump is known as one type of vacuum pump. In this turbo molecular pump, a motor in a pump body is energized to rotate a rotary vane, whereby gas (process gas) sucked into the pump body is separated into sub-streams and is discharged. In addition, there is a pump of siegesbee (also referred to as "siegesbee Ban En") among such turbo molecular pumps (patent documents 1 to 3). In the siegesbeck molecular pump, a plurality of swirl groove channels are formed in the gap between the rotary disk and the fixed disk, and are separated by the mountain. The siegesbeck molecular pump performs the exhaust by imparting tangential momentum to the gas molecules diffusing into the spiral groove flow path and imparting dominant directivity to the exhaust direction through the spiral groove flow path by rotating the disk. Further, a turbo molecular pump includes a screw groove pump (patent document 4). In the screw groove type turbomolecular pump, a screw groove spacer (70) and a rotor cylinder (10) are opposite to each other with a predetermined gap therebetween, and a screw groove is a flow path for conveying gas. Patent document 1 Japanese patent publication No. 6228839. Patent document 2 Japanese patent publication No. 6353195. Patent document 3 Japanese patent publication No. 6616560. Patent document 4, japanese patent application laid-open No. 2013-2174226. However, in the vacuum pumps such as the various turbo molecular pumps described above, the exhaust performance is improved by various designs. As an index of the exhaust performance, there are mainly "exhaust speed", "compression performance", and "back pressure characteristic". Among them, "exhaust speed" is an index simply representing the flow rate of gas that can be exhausted per unit time. The "compressibility" is an index of how much gas can be compressed, and relates to the case where the discharged gas is a compressible fluid. The "back pressure characteristic" is an index indicating the degree of influence of an auxiliary pump (booster pump) disposed downstream of the turbo molecular pump in the vacuum exhaust system. Based on the "back pressure characteristic", a limit back pressure capable of maintaining exhaust performance is determined. Further, according to the findings of the inventors, regarding the "back pressure characteristic", the limit back pressure that can maintain the exhaust performance is also related to the gas flow path volume (gas flow path volume), but is largely affected by the flow path length. Accordingly, the inventors have concluded that it is useful to lengthen the flow path length of the discharged gas when it is desired to improve the "back pressure characteristic". Disclosure of Invention The invention aims to provide a vacuum pump with excellent exhaust performance. (1) In order to achieve the above object, the present invention provides a vacuum pump including a siegesbeck exhaust mechanism having a swirl groove provided in at least one of a rotary disk and a stationary disk, and a hevigck exhaust mechanism having a spiral groove provided in at least one of a rotary cylinder and a stationary cylinder, wherein the hevigck exhaust mechanism is disposed downstream of the siegesbeck exhaust mechanism, wherein a flow path depth of the hevigck exhaust mechanism is continuously constant at a predetermined depth, and wherein the siegesbeck exhaust mechanism has a region continuously constant at the predetermined depth from a predetermined position. (2) In order to achieve the above object, another aspect of the present invention provides the vacuum pump according to (1), further comprising a plurality of layers of the siegesbeck exhaust mechanism, wherein a flow path depth of at least a lowermost layer of the siegbuck exhaust mechanism among the plurality of layers of the siegbuck exhaust mechanism connected to the holweck exhaust mechanism is continuously constant at the predetermined depth. (3) In order to achieve the above object, another aspect of the present invention is the vacuum pump according to (1) or (2), wherein a rotary vane and a stationary vane are provided on an upstream side of the siegesbeck exhaust mechanism, the rotary vane having a vane row, and the stationary vane being disposed at a predetermined interval from the rotary vane in an axial direction. Effects of the invention According to the above invention, a vacuum pump excellent in exhaust performance can be provided. Drawings Fig. 1 is an explanatory diagram schematically showing the structure of a turbo molecular pump according to an embodiment of the present invention. Fig. 2 is a circuit diagram of an amplification circuit. Fig. 3 is a timing chart showing control in the case where the current command value is larger than the detection value. Fig. 4 is a timing chart showing control in the case where the curren