CN205908489U - Adopt sectional type structure to pull compound molecule pump of level - Google Patents

Abstract

A compound molecular pump adopting segmented structure traction stage, the cylindrical traction stage adopts segmented structure, and the adjacent sections of the cylindrical traction stage are provided with circumferential grooves and circumferential bosses, and the circumferential concave The groove and the circumferential boss are arranged facing each other; when the stator is a smooth cylinder and the traction rotor is provided with a spiral groove, the circumferential groove is arranged on the traction rotor, the circumferential boss is arranged on the stator, and the traction rotor is formed from the circumferential concave The grooves are divided into several traction rotor segments; when the traction rotor is a smooth cylinder and a spiral groove is provided in the stator, the circumferential groove is arranged on the stator, the circumferential boss is arranged on the traction rotor, and the stator is divided into several sections by the circumferential groove. The stator segment; there is a spiral groove on the circumferential boss, and the spiral groove on the circumferential boss has the opposite spiral direction to the spiral groove on the traction rotor or stator; in the direction of air extraction, each traction rotor segment or stator segment The number of spiral grooves on the upper and circumferential bosses is set in an increasing manner, the groove depth of the spiral grooves is set in a decreasing manner, and the groove width of the spiral grooves is set in a decreasing manner.

Description

A Composite Molecular Pump Adopting Segmented Structure Traction Stage

technical field

The utility model belongs to the technical field of vacuum equipment, in particular to a composite molecular pump adopting segmented structure traction stages.

Background technique

Molecular pumps, as a kind of vacuum obtaining equipment that can obtain clean and high vacuum, have been widely used in many industrial fields. Among them, compound molecular pumps can still maintain high pumping performance in a wide pressure range. Therefore, in semiconductors, etc. It is widely used in the industry.

Existing compound molecular pumps are mainly divided into two categories, one is designed by the combination of turbo molecular pump and disc traction molecular pump, that is, the compound molecular pump with disc traction structure; the other is composed of turbo molecular pump and disc traction molecular pump. The barrel-type traction molecular pump is designed in combination, that is, the compound molecular pump with a barrel-type traction structure, which is the most commonly used compound molecular pump type at this stage.

For compound molecular pumps with a drum-type traction structure, in order to improve the gas compression capacity of the traction stage, the gap between the rotor and the stator of the traction stage is generally very small. Due to the limitations of machining accuracy, assembly accuracy, centrifugal deformation and thermal deformation of the rotor, the gap between the traction stage rotor and the stator can only be appropriately increased to ensure the working reliability of the compound molecular pump, but the traction stage rotor and stator The leakage of the gap between the stators will increase, which will lead to the performance degradation of the composite molecular pump, especially when the composite molecular pump works in the transition flow state and the viscous flow state, the leakage of gas along the gap will increase, which will seriously affect the performance of the composite molecular pump. The pumping performance of the pump.

Utility model content

Aiming at the problems existing in the prior art, the utility model provides a compound molecular pump adopting a traction stage with segmented structure, which can effectively improve the compression effect of the traction stage and further improve the pumping performance of the compound molecular pump.

In order to achieve the above object, the utility model adopts the following technical scheme: a compound molecular pump adopting a segmented structure traction stage, including a turbine stage, a cylindrical traction stage and a driving main shaft, and the turbine stage includes a stationary vane and a moving impeller, The cylindrical traction stage includes a traction rotor and a stator, and the moving impeller and traction rotor are fixedly set on the drive shaft. It is characterized in that: the cylindrical traction stage adopts a segmented structure, and the adjacent segments A circumferential groove and a circumferential boss are arranged between them, and the circumferential groove and the circumferential boss are arranged facing each other, and the axial centerline of the circumferential groove and the circumferential boss is aligned with the axial center of the drive spindle. Lines coincide.

When the stator is a smooth cylinder and a spiral groove is provided on the traction rotor, the annular groove is arranged on the traction rotor, and the annular boss is arranged on the stator.

The traction rotor is divided into several traction rotor segments by circumferential grooves, and in the direction of air extraction, the number of spiral grooves on each traction rotor segment is set to increase, and the depth of the spiral grooves on each traction rotor segment is set to decrease. The groove width of the helical groove on each traction rotor segment is set in decreasing order.

A spiral groove is opened on the circumferential boss of the stator, and the spiral groove on the circumferential boss and the spiral groove on the traction rotor have the opposite helical direction, and in the air extraction direction, each circumferential boss The number of helical grooves is set in increments, the depth of the helical grooves on each circumferential boss is set in a decreasing manner, and the width of the helical grooves on each circumferential boss is set in a decreasing manner.

When the traction rotor is a smooth cylinder and a spiral groove is provided in the stator, the annular groove is arranged on the stator, and the annular boss is arranged on the traction rotor.

The stator is divided into several stator sections by circumferential grooves, and in the direction of air extraction, the number of spiral grooves on each stator section is set in an increasing manner, and the depth of the spiral grooves on each stator section is set in a decreasing manner. The groove width of the spiral groove is set in a decreasing manner.

A spiral groove is opened on the annular boss of the traction rotor, and the spiral groove on the annular boss and the spiral groove on the stator have the opposite helical direction, and in the air extraction direction, each annular boss The number of helical grooves is set in increments, the depth of the helical grooves on each circumferential boss is set in a decreasing manner, and the width of the helical grooves on each circumferential boss is set in a decreasing manner.

The beneficial effects of the utility model:

The segmented structure traction stage adopted by the utility model, through the cooperation of the circumferential groove and the circumferential boss, can firstly partially block the gas leakage by means of the circumferential boss, and then solve the gas leakage between the traction stage rotor and the stator. Gap leakage problem, at the same time, with the help of the reverse spiral groove on the annular boss, the annular boss also has a certain compression capacity for gas.

The utility model divides the traction stage into several sections through the circumferential grooves opened, so that the conditions for setting spiral grooves with different parameters on each traction stage are met, that is, the number of spiral grooves is set in an increasing manner, and the number of spiral grooves is increased. The depth of the groove is set in decreasing order, and the width of the spiral groove is set in a decreasing manner. The traction stage of the above structure improves the compression effect of the gas, thereby further improving the pumping performance of the compound molecular pump.

Description of drawings

Fig. 1 is a kind of composite molecular pump (when the stator is a smooth cylinder and a helical groove is provided on the traction rotor) of the utility model that adopts a segmented structure traction stage;

Fig. 2 is a kind of composite molecular pump (when the traction rotor is a smooth cylinder and a spiral groove is provided in the stator) of the utility model that adopts a segmented structure traction stage;

In the figure, 1—stationary blade, 2—moving impeller, 3—traction rotor, 4—stator, 5—driving main shaft, 6—circumferential groove, 7—circumferential boss.

detailed description

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail.

As shown in Figures 1 and 2, a compound molecular pump adopting a segmented traction stage includes a turbine stage, a cylindrical traction stage and a drive main shaft 5, the turbine stage includes a stator blade 1 and a moving impeller 2, the The cylindrical traction stage includes a traction rotor 3 and a stator 4, and the moving impeller 2 and traction rotor 3 are fixedly set on the drive shaft 5. Its characteristics are: the cylindrical traction stage adopts a segmented structure, and the cylindrical traction stage A circumferential groove 6 and a circumferential boss 7 are arranged between adjacent segments, and the circumferential groove 6 and the circumferential boss 7 are arranged facing each other, and the axial direction of the circumferential groove 6 and the circumferential boss 7 The centerline coincides with the axial centerline of the drive spindle 5 .

When the stator 4 is a smooth cylinder and the traction rotor 3 is provided with a spiral groove, the circumferential groove 6 is provided on the traction rotor 3 , and the circumferential boss 7 is provided on the stator 4 .

The traction rotor 3 is divided into several traction rotor sections by the circumferential groove 6, and in the air extraction direction, the number of spiral grooves on each traction rotor section is set to increase, and the depth of the spiral grooves on each traction rotor section is gradually decreasing setting, the groove width of the helical groove on each traction rotor segment is set in a decreasing manner.

A spiral groove is opened on the circumferential boss 7 of the stator 4, and the spiral groove on the circumferential boss 7 and the spiral groove on the traction rotor 3 have the opposite helical direction, and in the air extraction direction, each ring The number of spiral grooves on the boss 7 is increasing, the depth of the spiral grooves on the bosses 7 is decreasing, and the width of the grooves on the bosses 7 is decreasing.

When the traction rotor 3 is a smooth cylinder and a spiral groove is provided in the stator 4 , the annular groove 6 is arranged on the stator 4 , and the annular boss 7 is arranged on the traction rotor 3 .

The stator 4 is divided into several stator sections by the circumferential groove 6, and in the air extraction direction, the number of spiral grooves on each stator section is set in an increasing manner, and the depth of the spiral grooves on each stator section is set in a decreasing manner. The groove width of the helical groove on the segment is set in decreasing order.

A spiral groove is opened on the annular boss 7 of the traction rotor 3, and the spiral groove on the annular boss 7 and the spiral groove on the stator 4 have the opposite helical direction, and in the air extraction direction, each ring The number of spiral grooves on the boss 7 is increasing, the depth of the spiral grooves on the bosses 7 is decreasing, and the width of the grooves on the bosses 7 is decreasing.

Below in conjunction with accompanying drawing, the one-time use process of the present utility model is illustrated:

When the compound molecular pump is working, the movable impeller 2 and the traction rotor 3 rotate with the driving spindle 5 at a high speed, and then carry the gas to flow downward along the spiral groove. The pressure difference between them is getting bigger and bigger, and the gas at this time will increase the leakage upward along the gap between the traction rotor 3 and the stator 4 under the action of the pressure difference, which will lead to the decline of the pumping performance and compression performance.

When the composite molecular pump adopts the traction stage with a segmented structure, the gas can be obviously blocked by the annular boss 6, thereby solving the problem of gas gap leakage between the rotor and the stator of the traction stage. The reverse spiral groove provided on the 6 makes the annular boss 6 also possess a certain compression capacity. Furthermore, because the traction stage is divided into several sections by the circumferential groove 7, and in the direction of air extraction, the number of spiral grooves on each traction stage section is progressively increasing, the depth of the spiral groove is decreasing, and the width of the spiral groove is It is arranged in decreasing order, and the traction stage of the above structure effectively improves the compression effect of the gas, thereby further improving the pumping performance of the compound molecular pump.

The schemes in the embodiments are not intended to limit the patent protection scope of the present utility model, and all equivalent implementations or changes that do not deviate from the utility model are included in the patent scope of the present case.

Claims (7)

1. A compound molecular pump that adopts a segmented structure traction stage, comprising a turbine stage, a barrel traction stage and a drive main shaft, the turbine stage includes stationary vanes and moving impellers, and the barrel traction stage includes a traction rotor and a stator , the moving impeller and the traction rotor are fixedly set on the drive shaft, and it is characterized in that: the cylindrical traction stage adopts a segmented structure, and circumferential grooves and circumferential grooves are arranged between adjacent sections of the cylindrical traction stage. The boss, the circumferential groove and the circumferential boss are arranged facing each other, and the axial centerlines of the circumferential groove and the circumferential boss coincide with the axial centerline of the drive spindle. 2. A compound molecular pump adopting segmented structure traction stages according to claim 1, characterized in that: when the stator is a smooth cylinder and a spiral groove is provided on the traction rotor, the circumferential groove is set On the traction rotor, said annular boss is arranged on the stator. 3. A compound molecular pump adopting segmented traction stages according to claim 2, characterized in that: the traction rotor is divided into several traction rotor segments by circumferential grooves, and in the pumping direction, The number of spiral grooves on each traction rotor segment is set in increments, the depth of the spiral grooves on each traction rotor segment is set in descending order, and the groove width of the spiral grooves in each traction rotor segment is set in descending order. 4. A compound molecular pump using segmented traction stages according to claim 3, characterized in that: a spiral groove is opened on the circumferential boss of the stator, and the spiral groove on the circumferential boss The grooves and the helical grooves on the traction rotor have the opposite helical direction, and in the direction of air extraction, the number of helical grooves on each circumferential boss is increasing, and the depth of the helical grooves on each circumferential boss is decreasing. The groove width of the spiral groove on each circumferential boss is set in a decreasing manner. 5. A compound molecular pump adopting segmented traction stages according to claim 1, characterized in that: when the traction rotor is a smooth cylinder and a spiral groove is provided in the stator, the circumferential groove is set On the stator, said annular boss is arranged on the traction rotor. 6. A compound molecular pump using segmented traction stages according to claim 5, characterized in that: the stator is divided into several stator segments by circumferential grooves, and in the pumping direction, each stator The number of spiral grooves on each segment is set to increase, the depth of the spiral grooves on each stator segment is set to decrease, and the width of the spiral grooves on each stator segment is set to decrease. 7. A compound molecular pump using segmented traction stages according to claim 6, characterized in that: a spiral groove is opened on the annular boss of the traction rotor, and the annular boss on the annular boss The helical groove and the helical groove on the stator have opposite helical directions, and in the air extraction direction, the number of helical grooves on each circumferential boss is increasing, and the depth of the helical grooves on each circumferential boss is decreasing. The groove width of the spiral groove on each circumferential boss is set in a decreasing manner.