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CN-119801874-B - Baking type ultrahigh vacuum low-temperature vacuum pump and control method

CN119801874BCN 119801874 BCN119801874 BCN 119801874BCN-119801874-B

Abstract

The invention discloses a baking type ultrahigh vacuum low-temperature vacuum pump and a control method, wherein the vacuum pump comprises a vacuum cover, a radiation-proof screen, a baffle plate and a condensation plate group; the refrigerator is provided with a primary refrigeration section and a secondary refrigeration section which are all extended into the cover body and are communicated with each other, the primary refrigeration section and the secondary refrigeration section are respectively provided with a primary temperature sensor and a secondary temperature sensor, and the heater, the cover body temperature sensor, the evacuation valve, the refrigerator and the primary temperature sensor and the secondary temperature sensor are respectively connected with the controller. The invention automatically heats the vacuum cover through the controller, the inner wall surface of the vacuum cover is heated and deaerated, the temperature of the refrigerator is increased under the influence of heat radiation in the process, at the moment, the refrigerator is controlled to start to reduce the temperature and keep within a certain range, the heating is stopped when the vacuum in the pump is reduced below a certain pressure value, and the refrigerator starts to reduce the temperature to the working temperature. The structure and the control method reduce the pre-evacuation treatment time before the cooling stage and realize the ultra-high vacuum state below 10 ‑9 torr.

Inventors

  • GUAN CHENGHONG
  • YANG CHEN
  • LU ZHENGYANG
  • CHEN JIE
  • LI YANFENG
  • LI AO

Assignees

  • 中船鹏力(南京)超低温技术有限公司

Dates

Publication Date
20260508
Application Date
20241219

Claims (7)

  1. 1. A control method of a baking type ultra-high vacuum low-temperature vacuum pump is characterized in that, The baking type ultrahigh vacuum low-temperature vacuum pump comprises a vacuum cover (20), a radiation protection screen (41), a baffle plate (42) and a condensation plate group (43), wherein the radiation protection screen (41), the baffle plate (42) and the condensation plate group (43) are contained in the vacuum cover (20), the baffle plate (42) covers the top of the radiation protection screen (41), the radiation protection screen (41) and the baffle plate (42) form a radiation protection screen cavity in a surrounding mode, the condensation plate group (43) is contained in the radiation protection screen cavity (36), the condensation plate group (43) is connected with a refrigerator (10), the baking type ultrahigh vacuum pump further comprises a heater (23) for heating the vacuum cover (20), a cover body temperature sensor (24) for detecting the temperature of the vacuum cover (20), an evacuation valve (25) communicated with the inner cavity of the vacuum cover (20), a primary refrigeration section (12) and a secondary refrigeration section (13) which are communicated are arranged on the refrigerator (10), the primary refrigeration section (12) and the secondary refrigeration section (13) extend into the vacuum cover (20), the primary refrigeration section (12) is connected with the secondary refrigeration section (13), the primary refrigeration section (12) is connected with the radiation protection section (41) and the secondary refrigeration section (13), the heater (13) is connected with the temperature sensor (13), and the primary refrigeration section (13) is arranged on the primary refrigeration section (13, and the heat sensor (13) is connected with the primary refrigeration section and the primary section (13 The cover body temperature sensor (24), the evacuation valve (25), the refrigerator (10), the primary temperature sensor (15) and the secondary temperature sensor (16) are respectively connected with the controller (30); The controller controls the opening of the evacuation valve (25), the gas molecules in the vacuum cover (20) are pumped by a front-stage pump connected with the interface (26) of the evacuation valve, the controller (30) collects gas molecules in the vacuum cover, the temperature T of the cover body temperature sensor (24) is collected when the pressure sensor is reduced to be lower than 1Torr, heating power of the heater (23) is controlled according to the temperature T, the temperature of the vacuum cover (20) is kept stable, heat is radiated to the inside after the heating temperature of the vacuum cover (20) is increased, the temperature of the primary refrigerating section (12) and the secondary refrigerating section (13) of the refrigerator (10) is increased by heating radiation, the controller (30) collects the temperature T1 of the primary temperature sensor (15) and the temperature T2 of the secondary temperature sensor (16), the temperature T1 or T2 is higher than 320K, the controller (30) controls the refrigerator (10) to operate, the T1 and T2 are reduced, the temperature sensors are kept to be lower than 320K and not lower than 290K, and the refrigerator (10) is turned off after the pressure (27) is reduced to be cooled to a certain value after the heating temperature is increased and evacuated, and the temperature of the refrigerator (10) is cooled.
  2. 2. The method of controlling a bake-type ultra-high vacuum cryopump according to claim 1, wherein the temperature T of the heating vacuum enclosure (20) is 100 to 250 ℃ and the pressure value P is lower than 10 -4 Torr.
  3. 3. The control method of the baking type ultra-high vacuum low temperature vacuum pump according to claim 1, wherein the inner cavity of the vacuum cover (20) is communicated with a pressure sensor (27) for detecting the pressure in the vacuum cover (20).
  4. 4. The method of controlling a bake-type ultra-high vacuum low temperature vacuum pump according to claim 1, wherein the heater (23) is provided on an outer wall surface of the vacuum housing (20).
  5. 5. The method for controlling a bake-type ultra-high vacuum low temperature vacuum pump according to claim 1, wherein the heater (23) is provided on an outer wall surface of the vacuum housing (20) in a ring-wound manner.
  6. 6. The control method of the baking type ultra-high vacuum low-temperature vacuum pump according to claim 1, wherein the refrigerator (10) comprises a motor (14) arranged outside a vacuum cover (20), and the motor (14) is sequentially connected with a primary refrigeration section (12) and a secondary refrigeration section (13) which are arranged in the radiation shield cavity.
  7. 7. The control method of the baking type ultra-high vacuum low temperature vacuum pump according to claim 1, wherein the vacuum cover (20) comprises a cover body (21), the upper end of the cover body (21) is connected with a cover body upper flange (22), and the lower end of the cover body (21) is connected with a cover body lower flange (28).

Description

Baking type ultrahigh vacuum low-temperature vacuum pump and control method Technical Field The invention relates to a vacuum pump and a control method, in particular to a baking type ultrahigh vacuum low-temperature vacuum pump and a control method. Background The low-temperature vacuum pump is a vacuum pump which utilizes an ultralow-temperature low-temperature plate and active carbon adhered on the plate to condense or adsorb gas. In this way, the cryopump pumps the chamber to which the cryopump is connected to achieve a vacuum state. Ultra-high vacuum refers to a vacuum state having a pressure of less than 10 -9 Torr (Torr, pressure unit). The vacuum which can be generally realized by the cryogenic vacuum pump at the present stage is between 10 -7 torr and 10 -9 torr, and although the cryogenic vacuum pump can continuously extract gas molecules in the vacuum chamber, the gas molecules on the metal surface can be continuously desorbed from the inner wall surface of the vacuum chamber, and the gas molecules outside the vacuum chamber can also continuously permeate the chamber wall to enter the chamber. The lower the pressure inside the chamber, the stronger the molecular desorption and molecular permeation capability outside the chamber, so the vacuum chamber pressure after being pumped by the cryogenic vacuum pump is also difficult to be lower than 10 -9 torr. Disclosure of Invention The invention aims to provide a baking type ultrahigh vacuum low-temperature vacuum pump which can reduce the pre-evacuation treatment time before the cooling stage and can realize an ultrahigh vacuum state below 10 -9 torr; The second object of the present invention is to provide a control method for full-flow automatic control of the above baking type ultra-high vacuum low temperature vacuum pump. The baking type ultrahigh vacuum low-temperature vacuum pump comprises a vacuum cover, a radiation protection screen, a baffle plate and a condensation plate group, wherein the radiation protection screen, the baffle plate and the condensation plate group are contained in the vacuum cover, the baffle plate covers the top of the radiation protection screen, the radiation protection screen and the baffle plate are surrounded to form a radiation protection screen cavity, the condensation plate group is contained in the radiation protection screen cavity, the condensation plate group is connected with a refrigerator, the baking type ultrahigh vacuum low-temperature vacuum pump further comprises a heater for heating the vacuum cover, a cover temperature sensor for detecting the temperature of the vacuum cover, an evacuating valve communicated with an inner cavity of the vacuum cover and used for extracting gas in the vacuum cover, the refrigerator is provided with a first refrigerating section and a second refrigerating section which are communicated with each other, the first refrigerating section and the second refrigerating section extend into the cover, the first refrigerating section is connected with the radiation protection screen, the second refrigerating section is connected with the condensation plate group, the first refrigerating section is connected with a first temperature sensor, and the second refrigerating section is connected with a second temperature sensor, and the heater, the evacuating valve, the first temperature sensor, the second temperature sensor and the second temperature sensor are respectively connected with a controller. Wherein, the vacuum cover inner chamber intercommunication has the pressure sensor who is used for detecting vacuum cover internal pressure. Wherein, the heater is arranged on the outer wall surface of the vacuum cover. The heater is arranged on the outer wall surface of the vacuum cover in an annular winding mode, or is wrapped on the outer wall surface of the cover body in a sheet-shaped heater mode. The vacuum cover comprises a motor arranged outside the vacuum cover, and the motor is sequentially connected with a primary refrigeration section and a secondary refrigeration section which are arranged in a cavity of the radiation-proof screen. The vacuum cover comprises a cover body, wherein the upper end of the cover body is connected with an upper flange of the cover body, and the lower end of the cover body is connected with a lower flange of the cover body. According to the control method of the baking type ultrahigh vacuum low-temperature vacuum pump, the controller controls the evacuating valve to be opened, gas molecules in the vacuum cover are pumped by the front-stage pump connected with the interface of the evacuating valve, the controller collects gas molecules in the vacuum cover, the heater is started when the pressure sensor is reduced to be below 1torr, the temperature value T of the cover temperature sensor is collected, the heating power of the heater is controlled according to the temperature value T, the temperature of the vacuum cover is kept stable, heat is radiated