Vacuumizing molecular pump unit with bypass pipeline

Abstract

The utility model provides a vacuumizing molecular pump unit with a bypass pipeline, which relates to the technical field of vacuum pumps and comprises a molecular pump and a backing pump. A transition air cylinder is arranged at the top of the molecular pump, the transition air cylinder is connected with an air inlet of the molecular pump, a connector and a bypass connector are arranged on the transition air cylinder, and the bypass connector is connected with the backing pump. The molecular pump unit disclosed by the utility model has the beneficial effects that the backing pump of the molecular pump unit can vacuumize the transition cavity in the transition air cylinder on the molecular pump in advance; therefore, the molecular pump can be directly started after the vacuum degree of the transition cavity reaches the vacuum degree required by the molecular pump, so that the vacuumizing time of the process cavity and the starting and stopping time of acceleration and deceleration of the molecular pump are saved, the air exhaust efficiency of the whole system is improved, and the service life of the molecular pump is prolonged. And the backing pump can pump out pollutants in the device to be vacuumized in advance, so that the pollutants in the device to be vacuumized are prevented from entering the molecular pump, and the molecular pump is ensured to operate under a safe working condition.

Description

Technical Field

[0001] The utility model relates to the technical field of vacuum pumps, in particular to a vacuum molecular pump unit with a bypass pipeline. Background Art

[0002] Molecular pump units are core equipment in the field of vacuum technology and are widely used in industries requiring extremely high vacuum environments, such as semiconductor manufacturing, materials science, aerospace, nuclear energy research, and medical equipment. Molecular pumps, with their high pumping speed, low vibration, low noise, and zero emissions, are key equipment for achieving high or ultra-high vacuum environments in these fields. A molecular pump unit typically consists of a molecular pump and a backing pump (which is required because the gas is in a molecular flow state). A molecular pump uses a high-speed rotating rotor to transfer momentum to gas molecules, imparting a directional velocity, thereby compressing and driving them toward the exhaust port for extraction by the backing pump. Its rotor speed can reach speeds exceeding 60,000 rpm. Starting the molecular pump requires a certain amount of starting pressure, resulting in a relatively long startup time. Molecular pump units have a complex structure and numerous high-precision components, resulting in relatively high maintenance costs. Particularly under high load or harsh operating conditions, component wear and failure rates can increase, further increasing maintenance costs. Molecular pumps are also sensitive to contaminants such as dust and water vapor. Inhalation of these contaminants can affect pump performance or even damage the pump. Therefore, environmental conditions need to be strictly controlled during use, which increases the difficulty and cost of use. Utility Model Content

[0003] In view of this, in order to improve the vacuuming efficiency of the molecular pump unit system, prevent pollutants from entering the molecular pump, and extend the service life of the molecular pump, the utility model provides a vacuum molecular pump unit with a bypass pipeline, comprising a molecular pump and a fore-stage pump;

[0004] A transition gas cylinder is provided on the top of the molecular pump, the cavity inside the transition gas cylinder is a transition cavity, the transition gas cylinder is connected to the air inlet of the molecular pump, and a connecting port and a bypass interface are provided on the transition gas cylinder, and the connecting port is used to connect to the device to be vacuumed;

[0005] The front-stage pump is provided with an inlet pipe, the bypass interface is connected to a bypass pipe, one end of the bypass pipe is connected to the bypass interface, and the other end is connected to the inlet pipe, and the air outlet of the molecular pump is provided with an exhaust connection pipe, and the exhaust connection pipe connects the air outlet of the molecular pump and the inlet pipe on the front-stage pump.

[0006] Furthermore, an air intake control solenoid valve is provided between the transition air cylinder and the air inlet of the molecular pump.

[0007] Furthermore, the air intake control solenoid valve is an electromagnetic pneumatic gate valve.

[0008] Furthermore, a vacuum gauge is provided on the top of the transition gas cylinder. The vacuum gauge is connected to the transition cavity in the transition gas cylinder and is used to measure the vacuum degree in the transition cavity.

[0009] Furthermore, the inlet pipe is provided with a three-way joint, the bypass pipe is connected to the three-way joint, and the three-way joint is provided with an on-off solenoid valve.

[0010] Furthermore, the system further includes a controller, which is connected to the molecular pump, the front pump, the vacuum gauge, the on-off solenoid valve and the air intake control solenoid valve.

[0011] Furthermore, it also includes a base plate, and the molecular pump, the front pump and the controller are all fixed on the base plate.

[0012] Furthermore, an annular connecting seat is provided at the bottom of the transition air cylinder, and the transition air cylinder is connected to the intake control solenoid valve through the annular connecting seat.

[0013] Furthermore, a mounting seat is provided at the bottom of the fore-stage pump, and the fore-stage pump is mounted on the base plate through the mounting seat.

[0014] Furthermore, a shock-isolating pad is provided at the bottom of the base plate.

[0015] The utility model provides a molecular pump unit with a bypass line, which has the following beneficial effects: the molecular pump unit includes a molecular pump and a backing pump; a transition gas cylinder is provided on the top of the molecular pump, the transition gas cylinder is connected to the air inlet of the molecular pump, the transition gas cylinder is provided with a connection port and a bypass interface, and the bypass interface is connected to the backing pump. The backing pump can pre-vacuum the transition chamber in the transition gas cylinder on the molecular pump and the process chamber of the device to be vacuumed. In this way, after the vacuum degree of the transition chamber reaches the vacuum degree required by the molecular pump, the plug valve can be closed and the process chamber can be operated without turning off the molecular pump, thereby eliminating the start-up and stop time required for frequent switching of the molecular pump, thereby improving the pumping efficiency of the entire system and extending the service life of the molecular pump. In addition, the pre-vacuuming of the transition chamber by the backing pump can first extract contaminants in the device to be vacuumed, preventing contaminants in the device to be vacuumed from entering the molecular pump, thereby protecting the molecular pump from the impact of contaminants and ensuring that the molecular pump operates under safe working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a stereoscopic diagram of a vacuum molecular pump unit with a bypass pipeline according to an embodiment of the present utility model.

[0017] Figure 2 It is a rear view of a vacuum molecular pump unit with a bypass pipeline according to an embodiment of the present utility model.

[0018] In the figure: 1-base plate, 2-molecular pump, 21-electromagnetic pneumatic plug-in valve, 3-foreline pump, 31-inlet pipe, 32-mounting seat; 4-controller, 5-transition gas cylinder, 51-connecting port, 52-annular connecting seat, 6-vacuum gauge, 7-bypass pipe, 8-tee connector, 81-on-off solenoid valve. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0020] Please refer to Figures 1 to 2 The utility model discloses a vacuum molecular pump unit with a bypass line, comprising a molecular pump 2, a front-stage pump 3 and a base plate 1, wherein the molecular pump 2 and the front-stage pump 3 are both fixed on the base plate 1.

[0021] The molecular pump 2 is arranged vertically, and a transition gas cylinder 5 is provided on the top. The cavity inside the transition gas cylinder 5 is a transition cavity. The transition gas cylinder 5 is connected to the air inlet of the molecular pump 2, so that the molecular pump 2 is connected to the transition cavity. A connecting port 51 and a bypass interface are provided on the transition gas cylinder 5. The connecting port 51 is used to connect to the device to be vacuumed.

[0022] The fore-stage pump 3 is provided with an inlet pipe 31, and the bypass interface is connected to a bypass pipe 7. One end of the bypass pipe 7 is connected to the bypass interface, and the other end is connected to the inlet pipe 31, thereby connecting the transition chamber to the fore-stage pump 3. The air outlet of the molecular pump 2 is provided with an exhaust connection pipe, and the exhaust connection pipe connects the air outlet of the molecular pump 2 and the inlet pipe 31 on the fore-stage pump 3. In this embodiment, the inlet pipe 31 is further provided with a three-way joint 8, and the bypass pipe 7 is connected to the three-way joint 8. The three-way joint 8 is provided with an on-off solenoid valve 81, and the on-off solenoid valve 81 is used to control the on-off of the three-way joint 8 (that is, the on-off solenoid valve 81 controls the on-off connection relationship between the fore-stage pump 3 and the transition chamber).

[0023] When the molecular pump 2 unit is working, the on-off electromagnetic valve 81 and the backing pump 3 are opened first, and the backing pump 3 vacuumizes the transition chamber in advance, so that the vacuum degree of the transition chamber can reach the vacuum degree required by the molecular pump 2, thereby directly starting the molecular pump 2. After closing the electromagnetic pneumatic gate valve 21, the molecular pump can operate the process chamber (the process chamber is the chamber to be vacuumed of the device to be vacuumed) without closing, thereby eliminating the need for the molecular pump 2 to frequently switch on and off, thereby improving the exhaust efficiency of the entire system. In addition, the backing pump 3 vacuumizes the transition chamber in advance and can first extract the pollutant communication gas in the device to be vacuumed, preventing the pollutants in the device to be vacuumed from entering the molecular pump 2, thus protecting the molecular pump 2 from the impact of pollutants, and ensuring that the molecular pump 2 operates under safe working conditions. And when the vacuum degree required by the device to be vacuumed is not too high, only the backing pump 3 can be started (without opening the molecular pump 2), so that the flexibility of the molecular pump unit can be improved.

[0024] Preferably, an air intake control solenoid valve is further provided between the transition gas cylinder 5 and the air inlet of the molecular pump 2. The air intake control solenoid valve is an electromagnetic pneumatic gate valve 21 (e.g., a DN63ISO-K electromagnetic pneumatic gate valve). The air intake control solenoid valve 21 can ensure that the molecular pump 2 is in a closed state when not in operation, thereby preventing impurities from entering the molecular pump 1.

[0025] Preferably, a vacuum gauge 6 is further provided on the top of the transition gas cylinder 5 , and the vacuum gauge 6 is connected to the transition cavity in the transition gas cylinder 5 . The vacuum gauge 6 is used to measure the vacuum degree in the transition cavity, so that the staff can observe the vacuuming condition of the front-stage pump 3 .

[0026] Preferably, an annular connecting seat 52 is provided at the bottom of the transition air cylinder 5 , and the transition air cylinder 5 is connected to the intake control solenoid valve 21 via the annular connecting seat 52 .

[0027] Preferably, a mounting base 32 is provided at the bottom of the fore pump 3, and the fore pump 3 is mounted on the base plate 1 via the mounting base 32. A vibration isolation pad is also provided at the bottom of the base plate 1. The vibration isolation pad can reduce the vibration impact of the entire molecular pump unit during operation.

[0028] Preferably, the molecular pump unit also includes a controller 4, which is fixed on the base plate 1. The controller 4 is simultaneously connected to the molecular pump 2, the front pump 3, the vacuum gauge 6, the on-off solenoid valve 81 and the intake control solenoid valve 21. The controller 4 is used to read the vacuum gauge parameters and control the on-off solenoid valve 81, the intake control solenoid valve 21 and the start and stop of the molecular pump 2 and the front pump 3, thereby automatically controlling the working process of the molecular pump unit and reducing the difficulty of the staff in operating the molecular pump unit.

[0029] In this document, directional terms such as front, back, top, and bottom are defined based on the positions of components in the accompanying drawings and relative to each other, and are intended only for clarity and convenience in describing the technical solution. It should be understood that the use of these directional terms should not limit the scope of protection claimed in this application.

[0030] In the absence of conflict, the above embodiments and features in the embodiments may be combined with each other.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A vacuum molecular pump unit with a bypass line, characterized in that: Including molecular pump and fore pump; A transition gas cylinder is provided on the top of the molecular pump, the cavity inside the transition gas cylinder is a transition cavity, the transition gas cylinder is connected to the air inlet of the molecular pump, and a connecting port and a bypass interface are provided on the transition gas cylinder, and the connecting port is used to connect to the device to be vacuumed; The front-stage pump is provided with an inlet pipe, the bypass interface is connected to a bypass pipe, one end of the bypass pipe is connected to the bypass interface, and the other end is connected to the inlet pipe, and the air outlet of the molecular pump is provided with an exhaust connection pipe, and the exhaust connection pipe connects the air outlet of the molecular pump and the inlet pipe on the front-stage pump.

2. A vacuum molecular pump unit with a bypass line according to claim 1, characterized in that: An air intake control solenoid valve is also provided between the transition air cylinder and the air inlet of the molecular pump.

3. The vacuum molecular pump unit with a bypass line according to claim 2, characterized in that: The air intake control solenoid valve is an electromagnetic pneumatic gate valve.

4. The vacuum molecular pump unit with a bypass line according to claim 3, characterized in that: A vacuum gauge is also provided on the top of the transition gas cylinder. The vacuum gauge is communicated with the transition cavity in the transition gas cylinder and is used to measure the vacuum degree in the transition cavity.

5. The vacuum molecular pump unit with a bypass line according to claim 1, characterized in that: The inlet pipe is further provided with a three-way joint, the bypass pipe is connected to the three-way joint, and the three-way joint is provided with an on-off solenoid valve.

6. The vacuum molecular pump unit with a bypass line according to claim 4, characterized in that: The device also includes a controller, which is connected to the molecular pump, the front pump, the vacuum gauge, the on-off solenoid valve and the air intake control solenoid valve.

7. The vacuum molecular pump unit with a bypass line according to claim 6, characterized in that: It also includes a base plate, and the molecular pump, the front pump and the controller are all fixed on the base plate.

8. The vacuum molecular pump unit with a bypass line according to claim 2, characterized in that: An annular connecting seat is provided at the bottom of the transition air cylinder, and the transition air cylinder is connected to the air intake control solenoid valve through the annular connecting seat.

9. The vacuum molecular pump unit with a bypass line according to claim 7, characterized in that: A mounting seat is provided at the bottom of the front pump, and the front pump is mounted on the base plate through the mounting seat.

10. The vacuum molecular pump unit with a bypass line according to claim 7, characterized in that: A shock-isolating pad is also provided at the bottom of the base plate.

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