WO2007041932A1

WO2007041932A1 - Double-drag molecular pump

Info

Publication number: WO2007041932A1
Application number: PCT/CN2006/002466
Authority: WO
Inventors: Jiguo Chu
Original assignee: Jiguo Chu
Priority date: 2005-10-10
Filing date: 2006-09-20
Publication date: 2007-04-19
Also published as: CN100513798C; CN1743680A

Abstract

A double-drag molecular pump which has simple structure, is easily mass produced, and can enhance the effective pumped rate is disclosed. The double-drag molecular pump includes a helical stationary impeller(1) and a dynamic seal stage(8) fixedly provided at a pump casing(3), and a movable impeller(2) fixedly provided at a rotor(22), wherein said movable impeller(2), stationary impeller(1) and dynamic seal stage(8) are alternatively arranged each other at a certain gap, an air inlet(31) and an air outlet(32) are correspondingly arranged on the pump casing(3), a motor(5) is mounted on one side of a rotary shaft(21), at the two ends of which are mounted an end covers(33), respectively, it is characterized in that a plurality of parallel-connected and serial-connected stationary impellers(1) are commonly mounted on the same frame (11)which consists of a fixed ring(34) and a brace strut(35), a plurality of blades (36)for the stationary impellers are provided on the fixed surfaces of the brace struts(35); no fixed ring is mounted on the inner and outer side of the blades for the stationary impellers. The double-drag molecular pump according to the present invention can be concentrically mounted with other molecular pump or rotary mechanical vacuum pump to form a compound vacuum pump with better operation performance. The double-drag molecular pump according to the present invention can be applied to a variety of molecular pumps and rotary mechanical vacuum pumps.

Description

Double drag molecular pump

The invention relates to a molecular pump, in particular to a double drag molecular pump. Background technique

Chinese Patent 87101116. 6 discloses a "molecular pump". Its purpose is to provide a radial flow molecular pump with two drag surfaces, high pumping speed, working pressure, exhaust gas flow can exceed dozens of times of the existing drag molecular pump, and such pumps and other rotating machinery A composite vacuum pump consisting of a vacuum pump. The shortcomings are:

1. The flow guide in the inner and outer gas passages of the static wheel is small, which reduces the effective pumping speed of the pump.

2. The structure of the static wheel is complicated, it is inconvenient to assemble, and it is difficult to mass production.

Invention disclosure

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dual drag molecular pump that is simple in construction, easy to mass produce, and that can increase the effective pumping speed of a pump, overcoming the deficiencies of the prior art described above.

The object of the present invention can be achieved by the following measures:

The double-drag molecular pump includes a spiral static wheel and a dynamic sealing stage fixed on the pump casing, and a moving wheel fixed on the rotor, and the moving wheel and the static wheel and the dynamic sealing stage are arranged in a staggered manner. The air inlet and the exhaust port are respectively arranged on the pump casing, and the motor is arranged on one side of the rotating shaft. The two ends of the rotating shaft are respectively provided with end caps, and the special features are as follows: a plurality of parallel and series static wheels share the same frame. The frame is composed of a fixing ring and a pillar, and the pillar fixing surface is provided with a static wheel blade; and the stationary wheel has no fixing ring in the inner side and the outer side.

The object of the invention can also be achieved by the following measures:

The static wheel blade is integrally formed with the pillar; the inner and outer sides of the blade of the static wheel are not provided with a fixing ring.

Confirmation The blade of the static wheel is integrally formed with the outer fixing ring thereof; the inner side of the blade of the static wheel is not provided with a fixing ring.

A plurality of parallel static wheels share a frame, and each of the columns is provided with a fixed surface for fixing the same integral blade in the same direction.

A plurality of series static wheels share a frame, and each of the columns is provided with two fixing faces for respectively fixing the blades in different oblique directions.

Several stages of parallel and series double-drag molecular pumping unit and several parallel and series of other rotary vacuum pumping units are coaxially installed, combined in series, and the air inlet near the pump is pumped by several parallel double-drag molecular pumps. The unit, the exhaust port close to the pump is a plurality of other rotary vacuum pump suction units connected in series, forming a horizontal composite double-drag molecular pump.

The coaxially mounted plurality of parallel rotary vacuum pumps in series and in series use one or a combination of a Siegbahn molecular pump suction unit and a Holweck molecular pump suction unit; a plurality of pumps connected in series close to the pump are selected from a Siegbahn molecular pump, Holweck One or a combination of molecular pumps.

The double shock absorbing structure adopted for the support of the rotor is composed of a damping ring provided between the outer side of the rotor bearing and the bearing seat, and a second damping ring provided between the bearing seat and the end cover.

The second layer of damping ring is an integral damping ring that is filled between the bearing housing and the end cap.

Several stages of parallel or series double-drag molecular pumping pumping unit and several stages of parallel or series of other vacuum pumping unit are installed coaxially, the turbo-molecular pumping unit and the parallel double-drag in series close to the inlet of the pump The molecular pump suction unit, the other rotary vacuum pump pumping unit connected in series with the exhaust port of the pump is a combination of a Siegbahn molecular pump pumping unit and a Holweck molecular pump pumping unit to form a vertical composite double-drag molecular pump. .

The present invention has the following advantages over the prior art:

1. Simple structure, easy to mass production. 2. Eliminating the inside of the suction passage, or eliminating the inner and outer fixed rings at the same time, increasing the inlet and outlet flow conductance of the suction passage, and improving the effective pumping speed of the pump;

3. It can be installed coaxially with other molecular pumps, or vacuum pumps such as rotary mechanical vacuum pumps, in parallel and in series to form a composite molecular pump with excellent performance.

DRAWINGS

1 is a schematic structural view of a parallel double-pushing pump of the present invention.

Fig. 2 is a cross-sectional view taken along line A-A of Fig. 1;

Fig. 3 is a schematic structural view of a parallel double-pumping pump static wheel frame.

Fig. 4 is a cross-sectional view taken along line A-A of Fig. 3;

Figure 5 is a schematic view of the knot of the parallel double-pumped pump stator blades.

Figure 6 is a cross-sectional view taken along line A-A of Figure 5;

Figure 7 is a schematic view of the structure of a parallel double-pumping pump.

Figure 8 is a schematic view of the integrated structure of the parallel double-pump pump blades and pillars.

Figure 9 is a cross-sectional view taken along line A-A of Figure 8;

Figure 10 is a schematic view of a series of double-pumping pump static wheel frames.

Figure 11 is a cross-sectional view taken along line A-A of Figure 10 .

Figure 12 is a schematic view showing the structure of a serial double-pumping pump.

Figure 13 is a schematic view of the overall structure of a single static wheel.

Figure 14 is a side view of Figure 13.

Figure 15 is a schematic view showing the structure of a first embodiment of a horizontal composite double-pumping pump.

Figure 16 is a schematic view showing the structure of a second embodiment of a horizontal composite double-pumping pump.

Figure 17 is a schematic view showing the structure of the double damper of the double-drag pump. Figure 18 is a schematic view showing the structure of a first embodiment of a vertical composite double-pumping pump.

Figure 19 is a schematic view showing the structure of a second embodiment of a vertical composite double-pumping pump.

In the figure:

1 - static wheel, 11 - frame;

2——moving wheel, 21^ shaft, 22——rotor;

3 - pump casing, 31 - air inlet, 32 - exhaust port, 33 - end cover, 34 - retaining ring, 35 - pillar, 36 - A ten;

4 - gas passage; 5 - motor;

6· Bearing, 61——Vibration ring, 62· ^Second layer damping ring, 63· ^ bearing seat;

71 - double-drag molecular pumping unit, 72 - Siegbahn molecular pumping unit; 73 - Holweck molecular pumping unit, 74 - turbomolecular pumping unit;

8 - dynamic sealing level; 9 · ^ JE reduction.

Best embodiment

The invention will be further described in detail below with reference to the accompanying drawings:

1, 2, 3, 4, 5, 6, 7, 8, and 9 show a first embodiment of the present invention.

Referring to FIG. 1 and FIG. 2, the parallel double-drag molecular pump includes a static wheel 1 fixed on the pump casing 3, and a moving wheel 2 fixed on the rotor 22, the moving wheel 2 and the stationary wheel 1 The staggered gaps are arranged, and the stationary wheels 1 connected in parallel at several stages share the same frame 11. The frame 11 is composed of a fixed ring 34 and a support 35, and the fixed surface of the support 35 is provided with static wheel blades 36. The rotor 22 is provided with six flat disc moving wheels 2, and between the adjacent moving wheels 2, five double tow pump stationary wheels 1 are respectively arranged. The tilting directions of the stationary vane blades 36 are all the same, and a double-drag molecular pump in which five sets of pumping units 71 are connected in parallel is formed. The outer circumference of the stationary wheel 1, and the inner side of the moving wheel 2 A gas passage 4 is provided. The static wheel 1 adopts a frame structure as shown in Figs. 3 and 4, and is composed of two fixing rings 34 and eight pillars 35. Each of the pillars 35 is provided with an integral vane 36 as shown in Figs. 5 and 6, and with this configuration, the conductance of the intake and exhaust ports of the suction passage can be increased, thereby effectively increasing the pumping speed. The assembled static wheel 1 is shown in FIG.

The stator blades and the struts can also be directly fixed to the two fixing rings 34 by using the blades 36 and the struts 35 as shown in Figs.

Operation process: When the moving wheel 2 rotates at an idling speed as indicated by the arrow in Fig. 2, the pumped gas is drawn from the outside of the stationary wheel 1 to the inside of the stationary wheel 1. The direction of the pumping direction can be changed by changing the direction of rotation of the moving wheel 2 or the direction of inclination of the stationary vane 36. Figures 10, 11, and 12 show a second embodiment of the present invention.

Referring to FIG. 10 and FIG. 11, the series double-drag molecular pump includes a static wheel 1 and a dynamic sealing stage fixed on the pump casing 3, and a moving wheel fixed on the rotor, the moving wheel and the stationary wheel 1 The movable seal stages are arranged in a staggered gap, and the static wheels 1 connected in series are shared by the same frame 11. The frame 11 is composed of a fixed ring 34 and a support 35. The fixed surface of the support 35 is provided with a spiral stator blade 36.

In this embodiment, the two-stage double-pumping pump unit is coaxially installed, and the two-stage unit of the static wheel 1 has opposite inclination directions, so that the suction direction is opposite, and the first-stage exhaust port is connected to the first-stage air inlet. A double-drag molecular pump that constitutes a series pumping. In the strut 35 of the static wheel frame 11 of the present embodiment, two fixing faces are provided, and the blades 36 of different inclination directions are respectively fixed. The assembled serial double-drag molecular pump static wheel 1 is shown in Figure 12.

Use process: When the moving wheel rotates at a high speed in the clockwise direction, the pumped gas in the upper static wheel is drawn to the inner rotating shaft from the outside of the static wheel, and the pumped gas in the lower static wheel is drawn from the inner side to the outside to form a series pumping. The direction of the pumping direction can be changed by changing the direction of rotation of the moving wheel, or the direction of inclination of the stationary vane 36. Figures 13 and 14 show a third embodiment of the present invention.

Referring to FIG. 13 and FIG. 14, the integrally formed static wheel double-drag molecular pump includes a static wheel 1 and a dynamic sealing stage fixed on the pump casing 3, and a moving wheel fixed on the rotor, the moving wheel and the moving wheel The staggered gap between the stationary wheel 1 and the dynamic seal stage is different from that of the first embodiment and the second embodiment in that each of the stationary vane blades 36 and the outer fixed ring 34 are integrally formed to form an independent unit. Then, the static wheel 1 is divided into two halves, and the inside of the blade is not provided with a fixing ring. With this structure, the machining accuracy is easy to ensure, and installation and debugging are convenient. Since there is no fixed ring on the inside of the static wheel 1, the flow guide of the inner port of the suction passage is relatively large.

The use process is as shown in Fig. 13. When the moving wheel rotates at a high speed in the clockwise direction, the pumped gas is drawn from the outside of the stationary wheel to the inner rotating shaft. The direction of the pumping direction can be changed by changing the direction of rotation of the moving wheel or the direction of inclination of the stationary vane 36. Fig. 15 and Fig. 17 show a fourth embodiment of the present invention.

Referring to FIG. 15 and FIG. 17, the horizontal composite double-pump pump includes a static wheel 1 and a dynamic seal stage 8 fixed on the pump casing 3, and a moving wheel 2 fixed on the rotor 22, the moving wheel 2 The air gap 1 and the air outlet 32 are respectively arranged on the pump casing 3, and the motor 5 is disposed on one side of the rotating shaft 21, and the two ends of the rotating shaft 21 are respectively set. End cap 33.

Several stages of parallel and series double-drag molecular pumping unit 71 and a plurality of parallel and series Siegbahn molecular pumping units 72 are coaxially mounted, combined in parallel and in series to form a horizontal composite double-drag molecular pump.

In this embodiment, the first pumping stage located in the middle portion is composed of five sets of double-drag molecular pumping units 71 in parallel. The two sides of the first pumping stage are respectively provided with two sets of double-drag molecular pumping unit 71 connected in series to form a second pumping stage, and the first and second pumping stages are respectively provided with a dynamic sealing stage 8, and the second pumping stage is respectively provided. The outer stage is provided with a compression stage 9 consisting of three sets of Siegbahn molecular pump suction units 72 connected in series. The support of the rotor employs a double shock absorbing structure as shown in FIG. The utility model comprises: a damping ring 61 is arranged between the outer side of the bearing 6 and the bearing seat 63; the cross section of the damping ring 61 can be circular or rectangular; and the second layer is reduced between the bearing seat 63 and the end cover. The vibration ring 62, the second layer of the damper ring 62 can be two circular sections, or a rectangular circle of 0, or an integral damping ring filled between the bearing seat 63 and the end cover 33. When the double damping device is used, the vibration and noise of the pump can be greatly reduced.

The double damper device of this embodiment can also be used for horizontal and vertical turbo molecular pumps and composite molecular pumps, as well as for other revolving shaft machines.

Process: The pumped gas enters from the inlet 31 of the pump, is pumped from the first pumping stage to the inner shaft, and then splits into the left and right sides, passes through the second pumping stage and the compression stage 9, and finally, The gas passage 4 is discharged from the exhaust port 32. Fig. 16 shows a fifth embodiment of the present invention.

Referring to FIG. 16, the horizontal composite double-drag molecular pump includes a static wheel 1 and a dynamic seal stage 8 fixed on the pump casing 3, and a moving wheel 2 fixed on the rotor 22, the moving wheel 2 and The static wheel 1 and the dynamic sealing stage 8 are arranged in a staggered gap. The pump casing 3 is respectively provided with an air inlet 31 and an exhaust port 32. The motor 5 is disposed on one side of the rotating shaft 21, and the two sides of the rotating shaft 21 are respectively provided with ends. Cover 33.

Several stages of parallel, series double-drag molecular pumping unit 71, Siegbahn molecular pumping unit 72, Holweck molecular pumping unit 73 are coaxially mounted, connected in parallel and in series.

In this embodiment, the first pumping stage located in the middle portion is composed of five sets of double-drag molecular pumping units 71. A second pumping stage consisting of three sets of Siegbahn molecular pumping unit 72 connected in parallel is arranged on both sides of the first pumping stage, and a dynamic sealing stage 8 is arranged between the first and second pumping stages, and the second pumping stage is provided. The compression stage 9 consisting of four sets of Holweck molecular pump suction units 73 connected in series is arranged on the outside.

Process: The pumped gas enters from the inlet 31 of the pump, is pumped from the first pumping stage to the inner shaft, and then splits into the left and right sides, passes through the second pumping stage and the compression stage 9, and finally, Gas channel 4, It is discharged from the exhaust port 32. Fig. 18 shows a sixth embodiment of the present invention.

Referring to FIG. 18, the vertical composite double-drag molecular pump is composed of a rotating shaft 21, a pump casing 3, a rotor 22, a turbo molecular pumping unit 74, a double-drag molecular pumping unit 71, and a dynamic sealing stage 8. The Siegbahn molecular pumping unit 72, the bearing 6, the motor 5, the gas passage 4, the air inlet 31, and the exhaust port 32 are formed. The upper and lower ends of the pump respectively have an air inlet 31 and an exhaust port 32, and the motor 5 is arranged on the shaft. Below the 21, an end cap 33 is fitted under the shaft 21.

A plurality of stages of turbomolecular pumping unit 74, a double-drag molecular pumping unit 71 and a Siegbahn molecular pumping unit 72 are coaxially mounted, and an air pumping port 31 close to the pump is provided with eight sets of turbomolecular pumping units connected in series. a first pumping stage composed of 74, a second pumping stage composed of two sets of double-drag molecular pumping unit 71 connected in series is arranged under the first pumping stage, and an exhaust port 32 close to the pump is arranged in series by three groups. The compression stage 9 consisting of a Siegbahn molecular pumping unit 72 forms a vertical composite double-drag molecular pump.

Use process: the pumped gas enters through the air inlet 31, passes through the first pumping stage, the second pumping stage, the compression stage 9 and the gas passage 4, and is finally discharged by the exhaust port 32. Fig. 19 shows a seventh embodiment of the present invention.

Referring to FIG. 19, the vertical composite double-drag pump is composed of a rotating shaft 21, a pump casing 3, a rotor 22, a turbo molecular pumping pumping unit 74, a double-drag molecular pumping unit 71, a dynamic sealing stage 8, and a Holweck. The molecular pump pumping unit 73, the bearing 6, the motor 5, the gas passage 4, the intake port 31, and the exhaust port 32 comprise a static wheel 1 and a dynamic seal stage 8 fixed to the pump casing 3, and are fixed The moving wheel 2 on the rotor 22 is arranged with a gap between the moving wheel 2 and the static wheel 1 and the dynamic sealing stage 8. The motor 5 is disposed below the rotating shaft 21, and an end cover 33 is disposed below the rotating shaft 21. Several stages of parallel, series-connected turbomolecular pumping unit 74, double-drag molecular pumping unit 71, several stages of series of Holweck molecular pumping unit 73 are coaxially mounted, and the inlet 31 of the pump is set up by eight groups. a first pumping stage composed of a turbomolecular pumping unit 74 connected in series, and a second pumping stage composed of two sets of double-dump pumping units 71 connected in series below the first pumping stage, close to the exhaust port 32 of the pump A compression stage 9 consisting of two sets of Holweck molecular pump suction units 73 connected in series is provided to form a vertical composite double-drag molecular pump. In this embodiment, the Holweck molecular pump pumping unit 73 can also be replaced by a Siegbahn molecular pump pumping unit.

Use process: the pumped gas enters through the air inlet 31, passes through the first pumping stage, the second pumping stage, the compression stage 9 and the gas passage 4, and is finally discharged by the exhaust port 32.

The above are only the preferred embodiments of the present invention, and all changes and modifications made within the scope of the claims of the present invention should fall within the scope of the appended claims. Industrial application

Claims

Claim

1. A double-drag molecular pump comprising a spiral static wheel and a dynamic seal stage fixed on a pump casing, and a moving wheel fixed on the rotor, wherein the moving wheel and the static wheel and the dynamic sealing stage have a gap therebetween Arrangement, the air inlet and the exhaust port are respectively arranged on the pump casing, and the motor is arranged on one side of the rotating shaft, and the two ends of the rotating shaft are respectively provided with end caps, wherein the plurality of parallel and series static wheels share the same frame. The frame is composed of a fixing ring and a pillar, and the pillar fixing surface is provided with a static wheel blade; and the stationary wheel has no fixing ring in the inner side and the outer side.

The double-drag molecular pump according to claim 1, wherein: the static wheel blade is integrally formed with the pillar; and the stationary wheel has no fixed ring disposed inside or outside the blade.

The double-drag molecular pump according to claim 1, wherein: the blade of the static wheel is integrally formed with the outer fixing ring; and the inner side of the blade of the static wheel is not provided with a fixing ring.

The double-drag molecular pump according to claim 1, wherein: a plurality of parallel static wheels share a frame, and each of the pillars is provided with a fixing surface for fixing the integral blades having the same inclination direction.

The double-drag molecular pump according to claim 1, wherein a plurality of series static wheels share a frame, and each of the columns is provided with two fixing surfaces for respectively fixing the blades in different oblique directions.

The double-drag molecular pump according to claim 1, wherein: a plurality of parallel and series double-drag molecular pumping units are connected coaxially with a plurality of other rotary vacuum pumping units connected in series, in series In combination, the air inlet near the pump is a plurality of parallel double-drag molecular pumping unit, and the exhaust port near the pump is a plurality of other rotary vacuum pumping units connected in series to form a horizontal composite double-drag molecular pump.

The double-drag molecular pump according to claim 6, wherein: the coaxially mounted plurality of rotary vacuum pumps connected in series and in series are selected from the group consisting of a Siegbahn molecular pump pumping unit and a Holweck molecular pump pumping unit. Or combination; several pumps connected in series near the exhaust port of the pump use one or a combination of a Siegbahn molecular pump and a Holweck molecular pump.

The double-drag molecular pump according to claim 6, wherein the double damping structure of the rotor is supported by a damping ring, a bearing seat and an end cover provided between the outer side of the rotor bearing and the bearing housing. It consists of a second layer of damping rings.

9. The dual drag molecular pump of claim 8 wherein: said second layer of damping ring is an integral damping ring that is filled between the bearing housing and the end cap.

10. The double-drag molecular pump according to claim 1, wherein: a plurality of stages of double-drag molecular pumping units connected in parallel or in series are coaxially mounted with a plurality of stages of other vacuum pumping units connected in parallel or in series, close to each other. The turbomolecular pumping unit of the pump inlet and the double-drag molecular pumping unit of the parallel, the other rotary vacuum pumping unit connected in series with the exhaust port of the pump are Siegbahn molecular pumping unit, Holweck molecule. One or a combination of pumping units constitutes a vertical composite double-drag molecular pump.