CN101985935A

CN101985935A - Three-axis Roots vacuum pump

Info

Publication number: CN101985935A
Application number: CN 201010565609
Authority: CN
Inventors: 刘坤; 巴德纯; 岳向吉; 李培印; 王光玉; 张振厚
Original assignee: Northeastern University China; Shenyang Scientific Instrument R&D Center of CAS
Current assignee: Northeastern University China; Sky Technology Development Co Ltd
Priority date: 2010-11-30
Filing date: 2010-11-30
Publication date: 2011-03-16
Anticipated expiration: 2030-11-30
Also published as: CN101985935B

Abstract

The invention relates to a vacuum pump, in particular to a three-axis Roots vacuum pump, which comprises a motor, a spindle and driven shafts, wherein the spindle is provided with a driving gear; driven gears meshed with the driving gear are arranged on the driven shafts; Roots rotors are arranged on the spindle and the driven shafts; and the two driven shafts are parallelly and symmetrically arranged on two sides of the spindle. The three-axis Roots vacuum pump has the characteristics of compact and symmetric structure, air suction under the action of the three axes and no oil in a pump cavity and realizes a high air suction speed.

Description

A kind of three Roots pumps

Technical field

The present invention relates to a kind of vacuum pump, be specifically related to a kind of three Roots pumps.

Background technique

Roots pump is a kind of vacuum pump commonly used in the industry such as semiconductor, photovoltaic industry, petrochemical industry, food processing, both can be used as the suction booster of high vacuum in being operated in, can be used as transmission pump again uses, can also plural serial stage form can discharging directly into atmosphere the dried pump of multi-stage roots, purposes is very extensive.But existing various forms of Roots pump all adopts two-axis, a driving shaft drives a driven shaft, not only the speed of exhaust is little, and since driving shaft to be subjected to the moment of flexure that periodic active force, rotor shaft be subjected to big, the rotor shaft dynamic balance performance is poor, vibration and noise are bigger than normal, thereby cause Roots pump pump energy consumption height, inefficiency.

Summary of the invention

At the existing problem of present Roots pump, the invention provides a kind of three Roots pumps, it is low to have solved the vacuum pump pumping efficiency, the problem of galloping.

Three Roots pumps of the present invention, comprise motor, main shaft and driven shaft, be equipped with driving gear on the main shaft, the driven gear that is meshed with driving gear is assemblied on the driven shaft, on main shaft and driven shaft, roots rotor is housed, it is characterized in that described driven shaft has two, the parallel and symmetrical both sides that are assemblied in main shaft.

The described roots rotor number of sheets is two leaves, four leaves, six leaves or eight leaves.

The described main shaft and the line of centres of two driven shafts on same cross section are straight line or triangle.

Described roots rotor progression is 1 grade～6 grades.

When described roots rotor progression is 2 grades～6 grades, separate with dividing plate between the adjacent two-stage.

The beneficial effect of the present invention's outstanding feature and generation compared with prior art is: increased by a driven shaft that has a roots rotor in main shaft one side, its three layouts and two gas circuit arrangement have improved the dynamic balance performance of vacuum pump, effectively reached the effect of vibration damping and noise reduction, the present invention has compact structure, symmetrical configuration, three effects are bled and the interior characteristics of not having oil of pump chamber, can realize the bigger speed of exhaust.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a horizontal type structure schematic representation of the present invention;

Fig. 3 is a vertical structure schematic representation of the present invention;

Fig. 4 is a pumping process schematic representation of the present invention;

The structural representation that Fig. 5 is triangularly arranged for the rotor cross-section line of centres;

Fig. 6 is the structural representation of three Roots pumps of single-stage;

Among the figure: 1 motor, 2 coupling, 3 main shafts, 4 driving gears, 5 right driven gears, 6 right driven shafts, 7 right driven roots rotors, 8 are roots rotor, 9 steps, 10 dividing plates, 11 left driven roots rotors, 12 left driven shafts, 13 left driven gears, 14 suction ports, 15 gear-boxes, 16 air-inlet cavitys, 17 upper bearing (metal)s, 18 motor framves, 19 bearing (ball) covers, 20 pump housings, 21 upper bearing brackets, 22 lower bearings initiatively.

Embodiment

The present invention will be further described below in conjunction with accompanying drawing.

A kind of three Roots pumps of example 1. the present invention, wherein motor 1 is connected with main shaft 3 by coupling 2, driving gear 4, left side driven gear 13 is connected by key with right driven gear 5 and is assemblied in main shaft 3 respectively, on left side driven shaft 12 and the right driven shaft 6, three axles are and are arranged in parallel, middle main shaft 3 is driven by motor 1, under three synchromesh gears drive, three axles are done reverse each other rotatablely moving, at main shaft 3, all be fixed with the roots rotor of Pyatyi 4 leaves on left side driven shaft 12 and the right driven shaft 6, roots rotor is separately fixed on three axles by the key connection, main shaft 3, the shaft shoulder place at left side driven shaft 12 and right driven shaft 6 two ends all is equipped with bearing, upper bearing (metal) 17 is fixed on the upper bearing bracket 21, the cavity of upper bearing bracket 21 inside links to each other with the relief opening of upper bearing bracket 21 sides, the upper-end surface of upper bearing bracket 21 links to each other with gear-box 15 by bolt, the shaft shoulder that extends to gear-box 15 at three axles partly is equipped with driving gear 4, left side driven gear 13 and right driven gear 5, gear-box 15 is connected with motor frame 18 by bolt, motor 1 is connected with motor frame 18 by bolt, the lower end surface of gear-box 15 is connected with the pump housing 20 by bolt, separate by dividing plate 10 between the roots rotor group of the pump housing 20 inside, dividing plate 10 is provided with three axis holes, below the axis hole of left driven shaft 12, open a pore, open a pore above the axis hole of right driven shaft 6, two pores are symmetrically distributed up and down along the straight line at axis hole place.Step 9 is connected with the pump housing 20 by bolt, the cavity of step 9 inside is an air-inlet cavity 16, have suction port 14 on the top of air-inlet cavity 16 step 9, suction port 14 is connected with air inlet pipeline, and bearing (ball) cover 19 is connected with step 9 by bolt.

Found out that by Fig. 4 roots rotor is by an air-breathing working procedure to exhaust, the figure section line is the distribution situation of mixed gas.When I figure position, the rotor of both sides sucks gas from pump intake.When forwarding II figure position to, the rotor of both sides continues air-breathing, encloses the gas of V0 volume, and the gas that drive is enclosed moves to exhaust side together.When forwarding III figure position to, the rotor of both sides is finished air-breathing, and the gas that drive is enclosed moves to exhaust side together.When going to IV figure position, the gas that the rotor of both sides is enclosed is about to communicate with relief opening, prepares exhaust.When going to V figure position, the gas that the rotor of both sides is enclosed communicates fully with relief opening, the beginning exhaust.Rotor set is so constantly rotated, and realizes continuous air extraction.

How roots rotor and axle are installed in the pump housing, have determined the general structure of pump.Mainly contain three kinds of patterns: first kind is horizontal, and as shown in Figure 2, the suction port of pump is last, and relief opening is following.This structural focus is low, and good stability when running up generally is used for large and medium-sized pump.Second kind is vertical, as shown in Figure 3.The inlet and outlet mouth of this structure is in a horizontal position, the assembling be connected all more convenient.But the center of gravity of pump is than higher, and poor stability when running up so be used for little pump more.The third is two install vertical with horizontal plane of rotor shaft.This structure fit up gap is controlled easily, and large, medium and small type pump all can adopt.

Working procedure of the present invention is: provide power source by motor 1, thereby drive main shaft 3 rotations.Main shaft 3 connects driving gear 4 by key, and left driven gear 13 is connected with right driven shaft 6 with left driven shaft 12 respectively with right driven gear 5, and main shaft 3 drives the rotation of two driven shafts.So just realized the synchronous rotation of roots rotor.Contactless engagement between rotor forms the space of sealing together with pump housing inwall, thus the air-breathing and exhaust of property performance period.

Separate with dividing plate 10 between the pump internal rotor.The gas that interaction is discharged between rotor and rotor, rotor and the pump housing inwall is finally discharged by relief opening by the gas channel of dividing plate 10.Under rotor rotation effects at different levels, realize the transport process of gas.Bigger pumping speed and the compression ratio that has improved pump reduces the consumption of energy, and dynamic balance performance is good, and running is steady, effectively vibration damping and noise reduction.

Example 2. its structures, connection is identical with embodiment 1 with working procedure, and difference is that the progression of roots rotor is 2 grades, and the number of sheets is 6 leaves.

Example 3. its working procedure are identical with embodiment 1, and difference is main shaft 3, and left driven shaft 12 and right driven shaft 6 are triangularly arranged. ?

Claims

1. three Roots pumps, comprise motor, main shaft and driven shaft, be equipped with driving gear on the main shaft, the driven gear that is meshed with driving gear is assemblied on the driven shaft, on main shaft and driven shaft, roots rotor is housed, it is characterized in that described driven shaft has two, the parallel and symmetrical both sides that are assemblied in main shaft.

2. a kind of three Roots pumps as claimed in claim 1 is characterized in that the described roots rotor number of sheets is two leaves, four leaves, six leaves or eight leaves.

3. a kind of three Roots pumps as claimed in claim 1 is characterized in that the described main shaft and the line of centres of two driven shafts on same cross section are straight line or triangle.

4. a kind of three Roots pumps as claimed in claim 1 is characterized in that described roots rotor progression is 1 grade～6 grades.

5. a kind of three Roots pumps as claimed in claim 4 when it is characterized in that described roots rotor progression is 2 grades～6 grades, separate with dividing plate between the adjacent two-stage.