CN1022504C - Integrated centrifugal pump and motor - Google Patents

Abstract

An integrated centrifugal pump and motor is provided by an impeller disk which contains permanent magnets and functions as the rotor for a brushless DC motor. The rotor is supported by non-contacting radial bearings and is hydrodynamically balanced against any axial thrust so that there is no contact between rotating and stationary elements during operation. Since the impeller disk is also the motor rotor, there is no need for a shaft, in the ordinary sense, which would penetrate the case and, thus, require seals. The resulting pump is compact and can be operated electronically at variable speeds.

Description

Integrated centrifugal pump and motor

Present invention relates in general to electronic fluid pump, relate in particular to the centrifugal pump of electronic no axle envelope.

Centrifugal pump is well-known in field of fluid machinery.Usually, this class pump comprises a motor, by this motor-driven axle and be installed in fluid impeller on this.Generally speaking, transport fluid on the center or hub of impeller by fluid input or suction port.Some blades on the impeller are protruding and be bearing between the hub disk with helical trajectory from hub usually, and this wheel disc forms the pumping passage together with blade.Rotor is encapsulated in the housing, and housing has working fluid is directed to passage on hub or the inducer from inlet, and inducer is directed to working fluid in the pumping passage between blade and the wheel disc.The centrifugal action of impeller is ordered about working fluid and is outwards entered in the diffuser on the hub disk circumference, enters a volute chamber and is transported to the exhaust port of pump from this volute chamber through the diffuser fluid.

The motor shaft of supporting impeller needs bearing, and this bearing can be lubricated by working fluid sometimes, still, in most of the cases, owing to working fluid and Lubricants can not be molten for one needs to separate, so above-mentioned bearing needs independent lubricating.With regard to all situations, need sealing to stop the leakage of inserting the axial working fluid of impeller in the pump case.After having used a period of time, bearing may allow running shaft have the place of radial displacement to produce wearing and tearing, like this, cause the quickening of wearing and tearing and the wearing and tearing of axle envelope, and caused working fluid from pump case to external leakage.

Existing centrifugal pump exists above-mentioned defective.Like this, clearly, need provide a kind of improved plan to go directly to overcome above-mentioned one or more shortcoming, to obtain more advantage.

Therefore, the object of the present invention is to provide a kind of impeller that in centrifugal fluid pump, also is used as the brushless DC electric machine rotor.

Another object of the present invention is to provide a kind of electric centrifugal pump, this centrifugal pump does not need axle envelope, and can offset any end thrust and realize hydraulic resistance balance.

The invention provides a kind of impeller that in centrifugal fluid pump, also is used as the brushless DC electric machine rotor, comprising: a hub part; The first and second dish type wheel discs; A plurality of pumping passages, they are by a plurality of protruding so that the blade that rotates at the common plane perpendicular to spin axis is formed from described hub part along a common plane between described first and second wheel discs; An inducer, it has the some pumping elements that separate with described impeller blade; Wherein: at least one the dish type wheel disc in the described dish type wheel disc is equipped with permanent magnet; Between described hub and described wheel disc, be provided with at least one path; In described path, be provided with one or more inducers.

In above-mentioned impeller, can be provided with a repetitive cycling passage near its each inducer.

The present invention also provides a kind of centrifugal pump, comprising: a housing, and it has the inner chamber that is communicated with entrance and exit; A disc rotor, it is bearing in the described inner chamber, can be around axis rotation, with the pumping working fluid; One is used for the drive motor rotor and makes its motor rotating stator coil; Wherein: described impeller has the permanent magnet that is installed in wherein, thus the also effect of electrizer rotor; Be provided with the 1st and the 2nd stator coil, be configured in the both sides of described impeller, between described impeller and coil, to constitute the gap, in order to accept the fluid of a small amount of pumping; Be provided with the 1st and the 2nd ring in described gap, the described the 1st and the 2nd ring is positioned on the identical radial location, in order to the working fluid that is pumped in this gap is carried out throttling, thereby provides axial hydraulic resistance balance to described impeller.

The advantage of the integrated electric centrifugal pump that the present invention is given is: compact structure, under the speed change situation, have automatically controlled ability, have one not need the no axle rotor that seals, when work, contactless radial bearing supporting is provided, and epitrochanterian fluid end thrust is able to balance.When compressible fluid of pumping or incompressible fluid, all can obtain above-mentioned these advantages.

Below in conjunction with accompanying drawing the present invention is described in detail, thereby makes above-mentioned feature and further feature more clear.

Fig. 1 is an embodiment's of a centrifugal pump of the present invention positive view;

Fig. 2 is another embodiment's of a centrifugal pump of the present invention positive view;

Fig. 3 is the partial sectional view that is cutd open along the line 3-3 in the pump shown in Figure 1.

Fig. 1 is an embodiment's of a pump of the present invention sectional view.As seen from Figure 1, this figure is in the represented vertical center plane of lateral symmetry center line in by figure.Housing 10 has 11 and outlets 12 of an inlet, and they couple together by inducer device 18, hub disk 15, on-bladed rotation diffuser 24 and volute chamber 13.The fluid of pumping separates after entering inlet 11; Both sides through inducer device 18; And see accompanying drawing 3) by the pumping passage 55(between two hub disks 15; Again through on-bladed rotation diffuser 24; Enter volute chamber 13 then and arrive outlet 12 again, impeller blade 21 that above-mentioned pumping passage 55 is adjacent and the space between the hub disk 15 form, and impeller blade 21 is arranged between the hub disk 15.Between diffuser 24 and volute chamber 13, a small part high-pressure liquid is back in the axial thrust balancing passage 45.These narrow passages provide required gap for the rotation of rotor disk 15 between stator 14.And the input by reflux fluid provides hydraulic resistance balance offsetting any end thrust of rotor 15, thereby rotor 15 is remained on the central position between the stator 14.On the surface of the stator shielding case 17 in the axial thrust balance channel 45 or be arranged on the outstanding position of housing 10.Because the axial clearance between hub disk 15 and stator shielding case 17 or the housing 10 is very narrow, therefore, these gimbals just make the hydrodynamic pressure in the balance channel 45 increase, thereby have increased the balance quality of end thrust.

Because in some cases, stator 14 can not be sealed or is wrapped, and therefore just need provide a kind of alternative to place axial thrust gimbal 16.In this case, be necessary to place axial thrust gimbal 16 at the protrusion position of housing 10.Each one side of something of housing 10 has an annular groove 33, and stator 14 is fixed in this groove.In addition, the return flow line 20 that is constituted has guaranteed to make the inducer stable working under non-design current velocity.

The rotor arrangement that comprises inducer device 18, wheel disc 15, impeller blade 21 and rotation diffuser 24 is bearing on the axle journal, this axle journal is arranged on the outside of the tubular shafts of wheel disc 15 to the extension, and the tubular shafts of wheel disc 15 is positioned at radial magnet bearing 35 and auxiliary bearing 40 to the extension.During work, rotor has an enough big gap to provide contactless bearing supporting for rotor by 35 supportings of radial magnet bearing between bearing 35 and the rotor.If magnet bearing 35 can not supporting rotor, so, auxiliary bearing 40 only promptly stops to do standby for thing followed rotor, has one between bearing 40 and the rotor than gap little between magnet bearing 35 and the rotor.

Each hub disk 15 includes a needed permanent magnet of the rotor along the brushless DC electric machine of circumferential arrangement, and at this moment this permanent magnet is used for and stator 14 that coil and power supply wiring be housed when contact takes place, as the constituent element of rotor.Because hub disk 15 is equipped with permanent magnet, and wheel disc 15 is bearing on radial magnet bearing 35 and the auxiliary bearing 40, so just do not need to penetrate any transmission shaft of housing 10, and also do not need rotary shaft sealing, otherwise because axle wearing and tearing and can finally cause leaking.

Figure 2 shows that another embodiment of pump of the present invention, in this example, housing 10 is made up of several sections, and two inlets 11 are arranged.These external all others, pump is identical on function.Owing to this reason, the used label of the label of each element and Fig. 1 is identical.

Figure 3 shows that the housing of 3-3 along the line among Fig. 1 and the local positive view of rotor.Blade 21 is fixed on the wheel disc 15.Inducer device 18 transports fluid on the blade, and blade pass crosses hub disk 15 and blade 21 formed pumping passages 55 pump the fluid radial outward.Diffuser 24 is formed by the space of the radial surface between two wheel discs 15, and blade 21 is in occupation of this radial surface.The fluid that is pressurized that comes out from diffuser 24 passes volute chamber 13 and is pulled away.

For the special design parameters of the application of a given pump, can determine by the requirement of pressure and volume, the qualification in space, the characteristic of working fluid and the orientation of desirable outlet and inlet.These are problems of be determining that following parameter will be considered, and they are: the size of the width of the diameter of hub disk 15, the spacing between the wheel disc and impeller blade 21, the size of required diffuser 24, inducer device 18, the size and dimension of pump case 10 and be the size that guarantees the return flow line 20 that the inducer stable working is disposed under non-design current velocity.Stator 14 and hub disk 15 will be complementary according to needed pump power.Whether stator 14 needs to be sealed in the shielding case 17, and this depends on whether working fluid is suitable for stator.

Claims (3)

1, a kind of impeller that also is used as the brushless DC electric machine rotor in centrifugal fluid pump comprises:

A hub part;

The first and second dish type wheel discs;

A plurality of pumping passages, they are by a plurality of protruding so that the blade that rotates at the common plane perpendicular to spin axis is formed from described hub part along a common plane between described first and second wheel discs;

An inducer, it has the some pumping elements that separate with described impeller blade;

It is characterized in that:

At least one dish type wheel disc in the described dish type wheel disc is equipped with permanent magnet;

Between described hub and described wheel disc, be provided with at least one path;

In described path, be provided with one or more inducers.

2, a kind of centrifugal pump comprises:

A housing, it has the inner chamber that is communicated with entrance and exit;

A disc rotor, it is bearing in the described inner chamber, can be around axis rotation, with the pumping working fluid;

One is used for the drive motor rotor and makes its motor rotating stator coil;

It is characterized in that:

Described impeller has the permanent magnet that is installed in wherein, thus the also effect of electrizer rotor;

Be provided with the 1st and the 2nd stator coil, be configured in the both sides of described impeller, between described impeller and coil, to constitute the gap, in order to accept the fluid of a small amount of pumping;

Be provided with the 1st and the 2nd ring in described gap, the described the 1st and the 2nd ring is positioned on the identical radial location, in order to the working fluid that is pumped in this gap is carried out throttling, thereby provides axial hydraulic resistance balance to described impeller.

3, a kind of impeller that also is used as the brushless DC electric machine rotor in centrifugal fluid pump comprises:

A hub part;

At least one dish type wheel disc;

By a plurality of protruding and be fixed on the formed a plurality of pumping passages of a lip-deep blade of described hub from described hub part;

An inducer, it has the some pumping elements that separate with described impeller blade;

It is characterized in that:

In described at least one dish type wheel disc permanent magnet is housed;

Between described hub and described wheel disc, be provided with at least one path;

In described path, be provided with one or more inducers;

Near inducing, each is provided with a repetitive cycling passage.

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