Summary of the invention
The purpose of this invention is to provide a kind of dry vacuum pump and rotor thereof, adopt the rotor shapes structure of symmetry, improved the dynamic balance performance of vacuum pump rotor effectively, effectively reduce the running noise of pump.
The object of the present invention is achieved like this:
A kind of dry type vacuum pump rotor that is used for, described vacuum pump comprise that the rotor of being made up of two rotors is right, and their phase mutually synchronization turn round in the other direction, rotor to and rotor and pump chamber between certain micro-gap is all arranged; Described rotor shapes has the cylindrical body of outer dog and imploded arcs groove for its cross section, its outer dog bi-side are cycloid, tip circle is a circular arc, imploded arcs groove bi-side are cycloid, bottom land is a circular arc, rotor be shaped as symplex structure, each rotor is provided with the imploded arcs groove of two or more outer dogs and equal amount.Outer dog radius of arc is 1.4 to 1.6 times of rotor radius, and imploded arcs groove radius of arc is the poor of root diameter and outer dog radius of arc, and circular arc and cycloid intersection seamlessly transit.
A kind of dry vacuum pump, described vacuum pump comprise that the rotor of being made up of two rotors is right, and their phase mutually synchronization turn round in the other direction, rotor to and rotor and pump chamber between certain micro-gap is all arranged; Described rotor shapes has the cylindrical body of outer dog and imploded arcs groove for its cross section, its outer dog bi-side are cycloid, tip circle is a circular arc, imploded arcs groove bi-side are cycloid, bottom land is a circular arc, rotor be shaped as symplex structure, each rotor is provided with the imploded arcs groove of two or more outer dogs and equal amount; Suction port, relief opening circular arc arc length account for 40 to 60 degree of whole circumference, rotor twice of the suction and discharge that whenever rotate a circle.
It is-22 to-24 to spend positions, air-breathing end that rotor in the intakeport pump chamber goes to outer dog end to the line of rotor axis and two rotor axis line angles; It is 16 to 18 to spend positions that rotor in the relief opening pump chamber goes to outer dog front end to the line of rotor axis and two rotor axis line angles, begins exhaust.Rotor to the gap be 0.0010 to 0.0014 times of rotor radius, the gap of outer dog and pump chamber is that 1.1 to 1.5 times of rotors are to a gap, the gap of rotor exhaust side and pump chamber be 1.0 to 1.4 times of rotors to a gap, the gap of rotor air inlet side and pump chamber is that 1.5 to 2.8 times of rotors are to a gap.Pump chambers at different levels have all designed gas ballast port, the gas ballast port position on 0.75 to 0.85 times rotor radius, and with the angle of two rotor axis lines be 20 to 60 degree.Two key linkage structures are adopted in being connected of rotor and axle, and rotor shaft hatch is provided with two keys of symmetry, and axle is provided with elongated two keyways, and the position of the position of upper level rotor key and next stage rotor key differs 90 degree.The relief opening of pump has also designed baffler and atmospheric valve, and baffler comprises left side adapter, pressure spring, spacer, stud, right adapter, pad one, fluorine rubber plate, intermediate plate, pad two; A left side is taken over and is positioned on the relief opening, be provided with the fluorine rubber plate between left side adapter and right the adapter, fuse with bolt, be provided with mounting hole in the middle of the fluorine rubber plate, be provided with vent around the mounting hole, stud bolt the inner is fixed on this mounting hole by intermediate plate and nut, stud is positioned at right the adapter, be equipped with pad one on the stud, pad one outside is equipped with pressure spring, spacer, pad two, the stud bolt outer end is fixed with nut, and pad one spring pressure that is stressed is pressed on the fluorine rubber plate, blocks vent; When the pressure of inner chamber reaches certain value greater than the pressure of exocoel, gas forces its outside cavity direction surrender by pad one compression pressure spring, gas is just discharged by the slit between pad one and fluorine rubber plate, the number of times of discharging is the same with the exhaust number of times of pump, and flow is determined by the pressure in the pump inner chamber; After gas was discharged, the pressure of inner chamber reduced, and then pad one resets under the pressure of spring fast.
The present invention has following advantage and good effect:
As adopt each suction and discharge twice that whenever rotate a circle of two pawl rotors, rotor, and the suction and discharge number of times of pump is increased, single suction tolerance reduces, and has reduced the running noise of pump.As adopt four-stage pump can reach capacity degree of vacuum near 3Pa.The present invention can be widely used in environment such as space flight, chemical industry, nuclear industry.Can solve to be used to take out in China's special industry contain and be corrosive as HF H
2SO
4, HNO
3, HCL gas, condensable gas such as water vapor, radioactive air.Multistage pump can be made, also single-stage etc. can be designed to.It can also be used to do the gas transmission pump and use.
Embodiment
Describe the present invention in detail below in conjunction with drawings and Examples.
Each component names of the present invention and reference character are as follows:
Suction port 1, primary rotor be to 2, first-stage pump body 3, the secondary rotor is to 4, and 5, three grades of rotors of second-stage pump body are to 6, triplex body 7, level Four rotor be to 8, the level Four pump housing 9, base 10, fuel tank 11, fuel tank spindle nose sealing 12, base spindle nose sealing 13, apical axis head sealing 14, atmospheric valve 15, baffler 16, fluororubber O-type seal ring 17, driving shaft 18, driven shaft 19, driving gear 20, driven gear 21, coupling 22, gas ballast valve 23, bleed valve 24, gas channel 25, passage plug 26, inter-stage relief opening 27, inter-stage suction port 28, gas ballasting aeration mouth 29.
1. working principle: driven by motor coupling 22 work, thereby driving gear 20 and driven gear 21 motion in the other direction synchronously, primary rotor 2 motions form vacuum, by relief opening 27 and gas channel 25 gas is discharged in the second level pump housing 5, secondary rotor in the second level pump housing 5 is to doing same work with first order rotor to 2, then, be discharged to next stage one by one, in the fourth stage pump housing; Then, gas is discharged by baffler 16.Shown in Fig. 6-10: the x chamber is the air aspiration cavity of the pump housing, and the y chamber is the exhaust cavity of the pump housing, and 29 is gas ballasting aeration mouth; When rotor air aspiration cavity x minimum when running to position shown in Figure 6, beginning and inter-stage suction port 28 are connected, and pump chamber begins air-breathing, and the volume maximum angle of air aspiration cavity is-22.8 to spend air-breathing subsequently end when position shown in Figure 7; When rotor runs to position shown in Figure 8, be 17.8 degree, the pressurized gas of exhaust cavity y begins to connect with inter-stage relief opening 27, and pump chamber begins exhaust; Simultaneously, gas ballasting aeration mouth 29 beginning aeration in exhaust cavity y, exhaust finishes during to position shown in Figure 9; Exhaust cavity y minimum.Residual gas has been discharged into the y chamber before position shown in Figure 10, enter into next exhaust process.
2. the molded lines shape of rotor; As shown in Figure 5, the molded lines of rotor is by six circular arc AB arcs, the DE arc, and the GH arc, the JK arc, the MN arc, PQ arc and six cycloid BC, FG, HI, KL, OP, QR, all the other RA, CD, EF, IJ, LM, NO line are that circular arc and cycloid intersection seamlessly transit line.Wherein the radius of AB arc and JK arc is outer dog radius R M, and the radius of DE arc and MN arc is rotor radius R, and the radius of GH arc and PQ arc is imploded arcs groove radius r.The gap of rotor engaged is in sealing and expansion gap, and evenly, its gap length is: in the scope of t=R * 0.0012 (positive and negative 0.01mm), thus easy to process, make the efficient of processing increase substantially processibility and the dynamic balancing effect that has improved pump rotor effectively.
3. the phase place of pump rotors at different levels: the rotor in the pump housings at different levels is to not installing by unified direction, and is vertical mutually between them, differs an angle of 90 degrees; Purpose is when guaranteeing that gas in the first order pump housing is discharged, second and the pump housing be in suction condition, gas flow is unimpeded.
4. the Position Design of suction port and relief opening: the suction port of pump and all corresponding adjustment in position of relief opening simultaneously with gas ballast port, the angle of relief opening and vertical line is in 27 degree (once positive and negative) scopes, total angle is in 54 degree (the positive and negative 1 degree) scope, the angle of suction port and vertical line is in 27 degree (once positive and negative) scopes, total angle is in 54 degree (the positive and negative 1 degree) scope: width is Kd=(R-r-10) mm, satisfy pump rotor and whenever rotate a circle each suction and discharge once to the needs of twice of each suction and discharge of whenever rotating a circle, the suction and discharge number of times of pump is increased, and single suction tolerance reduces the running noise that effectively reduces pump.
5. the design of gas ballasting and effect: as shown in Figure 6: pump chambers at different levels all are provided with gas ballast port, and its particular location is R=(0.75-0.85) * R; The size of gas ballast port is about M=R/10 for diameter, and big pump can be got big value, and little pump gets the small value, and angle is 42 degree, can be in positive and negative 2 degree scopes; Gas replenishment process: run to exhaust position with rotor, as shown in Figure 8, in 17.8 degree angle positions, gas ballasting hole and exhaust cavity are connected, if the pressure of exhaust cavity is less than 1 barometric pressure at this moment, then gas ballasting is started working, just the dry gas at pump chamber place charges into.The amount of charging into can manual tune by gas ballast valve 23, and the time of charging into is the every running tour of rotor, charges into 2 times in 50 degree scopes, and frequency is 2 times of motor rotation frequency.
6. doubly linked necessity: as shown in Figure 5: being connected of rotor and axle adopts the symmetric double key to connect, simultaneously, rotor itself has two keys of symmetry, its size designs by NBS according to the size of axle: the interchangeability that guarantees rotor, and avoid the gas leakage that splines and brought on the rotor, make the loading and unloading of pump very convenient, pump can reach higher limiting vacuum.
7. clearance seal and gap length: as shown in Figure 5: rotor to and and pump chamber between all have certain micro-gap, rotor is that the gap of t1=R * 0.0012 (positive and negative 0.01mm) rotor tip circle RM and pump chamber internal surface is t2=1.5 * t1 to a gap length, the lower surface of rotor (exhaust side) is t3=(1.2-1.3) * t1 with the gap of pump chamber, and the upper surface of rotor (air inlet side) is t4=2 * t3 with the gap of the outside bottom surface of pump chamber; Guarantee that rotor can run well, and do not have friction.
8. the effect of bleed valve: as shown in Figure 3, first order pump chamber has also designed bleed valve, and when the pressure in the pump chamber was higher than an atmospheric pressure, bleed valve was opened, and gas is discharged, and lowers the power consumpiton of what rotor of back.
9. the effect of baffler 16: as shown in Figure 2, the relief opening of pump has also designed baffler 16 and atmospheric valve 15.As shown in Figure 4, the structure of baffler is to take over 1601 by a left side, pressure spring 1602, spacer 1603, stud 1604, right adapter 1605, pad 1, fluorine rubber plate 1608, intermediate plate 1609, pad 2 1610 compositions such as grade.A left side is taken over and is positioned on the relief opening, be provided with the fluorine rubber plate between left side adapter and right the adapter, fuse with bolt, be provided with mounting hole in the middle of the fluorine rubber plate, be provided with vent around the mounting hole, stud bolt the inner is fixed on this mounting hole by intermediate plate and nut, stud is positioned at right the adapter, be equipped with pad one on the stud, pad one outside is equipped with pressure spring, spacer, pad two, the stud bolt outer end is fixed with nut, and pad one spring pressure that is stressed is pressed on the fluorine rubber plate, blocks vent; Its working principle is when the pressure in A chamber reaches certain value greater than the pressure in B chamber, gas forces it to surrender to the B cavity direction by pad one compression pressure spring 1602, gas just passes through the slit of 1608 of pad 1 and fluorine rubber plates and discharges, the number of times of discharging is the same with the exhaust number of times of pump, and flow is determined by the pressure in the pump A chamber.After a gas was discharged, because the pressure in A chamber reduces, then pad 1 resetted under the pressure of spring fast, played the effect that prevents the gas back diffusion and reduce noise.The critical pressure that pad one is opened is: P2=F0/S+P1.P2 is an A chamber instantaneous pressure peak value, P1=external pressure (1 barometric pressure), the sectional area of S=intermediate plate 1609 upper air-vents, the pressure of F0=spring under original state.The individual barometric pressure of P2=(1.1~1.3) is got in final design, regulates spacer 1603 after the assembling as required, to reach the best effort effect.The left side of baffler is taken over 1601 and is connected with the fourth stage pump housing 10, and sealing seals with fluororubber O-type ring.
10. the effect of atmospheric valve 15: the effect that it plays out and closes needs to open atmospheric valve the liquid that accumulates is discharged after pump is taken out condensable gas.Avoid liquid suck-back after the termination of pumping, restart the catastrophic failure that bring this pump the back.
Rotor radius refers to that rotor is to the tangent circle radius.It is preferred construction that the utility model adopts two pawl rotors.