WET RUN CENTRIFUGAL PUMP AGGREGATE

The invention concerns a wet run centrifugal pump aggregate with the characteristics indicated in the generic term of the requirement 1.

Wet run centrifugal pump aggregates of this kind are used for example as circulating heating pumps millionfold in the world. They work usually with a synchronous engine, whose rotor from a rotor bundle of laminations on the motor shaft is formed for a sitting, which is provided with recesses close its extent, to which from copper or aluminum existing short-circuit staffs are introduced, those finallaterally with a seal plate or a sealing ring by Schweiβ EN or rivets are connected. In order to protect on the one hand the stator reliably against the promotion liquid to ensure on the other hand however a cooling of the engine and lubrication in particular the Wellenlagers on the engine side a Spaltrohr is intended, that the rotor area, which can be filled either with promotion liquid or another liquid, opposite the stator seals. This Spaltrohr is usually made of austenitic, not rusting steel sheet. Despite numerous detail improvements the efficiency of these pump units working with synchronous engine is not to be increased on the engine side at economically justifiable expenditure practically no more. Permanent magnet engines, which are not so easily operable however with the alternating current standing from the net to the order, are to that extent more favorable. It is regelmä&szlig for this; industrial union static frequency changer electronics necessarily, which increases the manufacturing costs substantially.

From DE 25 28 808 C2 it is well-known to use for the improvement of the efficiency of a synchronous engine a magnetically leading Spaltrohr. But this Ma&szlig has itself; nahme in particular with centrifugal pump aggregates as a little practicably proven, since those are rather small efficiency paste run gene, the technical expenditure however highly, there the materials for a economical Gro&szlig, indicated there; quantity production are a little suitable.

It ranks the short-circuit staffs in the rotor among the state of the art, by Gieß EN von Aluminium or an aluminum alloy to form, however is quite aufwändig this procedure, so that it only with engines of middle Größ e, not however the synchronous engines of small Grö&szlig here in speech; e is used. Beyond that also here the improvement of efficiency is marginal.

Before this background the available invention the task is the basis, gattungsgemäß to increase it wet run centrifugal pump aggregate at economically justifiable expenditure in its efficiency.

This task becomes gemäß the invention by the characteristics indicated in requirement 1 solved. Favourable arrangements of the invention are indicated in the Unteransprüchen, the following description as well as the figures.

Those erfindungsgemäß e solution sees several constructional Ma&szlig for improvement of efficiency; made, which in their effect synergetically complement each other, thus in their combination in the efficiency increase over the sum of the Einzelmaß took clearly go out. The short-circuit staffs are educated by copper or a copper alloy, that are cast in into the rotor bundle of laminations, so that a high gap-free filling degree develops within the rotor bundle of laminations of this high-leading material. Because also the Spaltrohr from ferritic, stainless steel is obtained, not only an additional efficiency increase of the engine, but beyond that also the effect is formed at the same time that due to the Kurzschlussstabvergussmaß nahme increased magnetic river also better by the Spaltrohr through-arrives. In this way anyhow the efficiency of a wet run centrifugal pump aggregate of the kind initially specified, in particular also small and/or middle achievement between 50 and 250 Watts, can be so far improved that it is not inferior today common direct current permanent magnet engines. Ma&szlig are in further training of the invention; took intended, which an economic manufacturing possible make, in particular the manufacturing in existing production lines, without größ to make ere interferences.

If the rotor bundle of laminations, which actually admits is, is preferential, trained. Since that cabinets differently than with the state of the art, with which the rotor staffs are first introduced and fastened finallaterally, before actual cross-setting takes place, before that manufacturing the rotor staffs effected, knows on the one hand the cross-setting of the rotor bundle of laminations substantially more exactly and gleichmäß more iger than with the state of the art to take place and on the other hand the entire free space formed in the rotor bundle of laminations via sealing compound be filled out. The twisting angle between neighbouring sheet metals can thus with that erfindungsgemäß EN construction with substantially higher accuracy to be kept than with constructions, with which the short-circuit staffs are pressed into the rotor bundle of laminations. By the higher filling degree becomes the leading cross section, which improves magnetic river and thus also the efficiency. Beyond that becomes gleichmä&szlig by those; ige cross-setting a calm and comparatively noiseless run with high efficiency ensures.

Around the rotor staffs finallaterally kurzzuschließ EN, is usually applied a copper disk or a copper ring to both sides of the rotor bundle of laminations, which are connected with the rotor staffs leading. Gemäß these stators are formed for the invention just like the rotor staffs by capping. Thus stators and rotor staffs in a processing step can be manufactured. Thereby not only a outstanding line, but beyond that also a firm and positive group of the entire rotor bundle of laminations is reached.

Preferred the Spaltrohr is trained in form of a gap tubing pot, since then no separate wave sealing is necessary to the engine. This actually favourable constructional Maß nahme is in the Groß quantity production economically possible only if the gap tubing pot can be made to a large extent by deformation work of a sheet metal. This was so far only conditionally possible however with ferritic materials. The invention sees gemä&szlig for this in a further training; the requirements 5 to 9 an alloy forwards, which ensures this despite the ferritic, i.e. well magnetically conductive characteristic and the corrosion resistance. Such an alloy exhibits a carbon content from 0,01 to 0.05 between 15 and 20 weight percentage, preferably between 16 and 18 weight percentage chrome, has, preferably between 0,02 and 0,04 a weight percentage and a nickel portion under 1 weight percentage. It can be done also without nickel completely. Besides further alloying elements can be present such as manganese, molybdenum, titanium, niobium as well as silicon in the alloy, whose total portion is not to exceed however 3 weight percentage.

Since the rotor runs usually in the promotion liquid and a corrosion of the rotor bundle of laminations reliably to be avoided is, since already smallest deposits would block the run of the rotor, one turns into more and more to encase the rotor completely by a sheet-steel jacket in order to be able to optimize so the construction units lying within the rotor better regarding the magnetic characteristics. During this construction a further efficiency increase can be obtained by the fact that also the sheet-steel jacket used for the packaging of the rotor is formed for out not rusting, ferritic steel. For this sheet metals can be used, which consist of the above-mentioned materials.

The invention is in the following described on the basis a remark example represented in the design more near. Show:

Fig. 1

in simplified representation a profile by a wet run centrifugal pump aggregate,

Fig. 2

in vergröß erter representation the copper capping body of the rotor,

Fig. 3

in further vergröß erter representation a cross section by a rotor after the invention and

Fig. 4

a cross section by a comparable rotor after the state of the art.

On the basis of Fig. 1 represented wet run centrifugal pump aggregate exhibits an electric motor 1, which propels a centrifugal pump 2. To the electric motor 1 taking up crankshaft housings 3 schließ t itself a pump housing 4 on, in which a gyroscope wheel 5 of the pump runs. The promotion liquid arrives to the pump housing 4 over a intake 6 at the Saugmund of the Kreiselrads 5 and from there over a printing connecting piece 7 out.

The gyroscope wheel sits on a wave 8, which is stored within a gap tubing pot 9, which seals the Pumpenraum opposite the engine compartment. Within the gap tubing pot 9 a rotor 10 on the wave 8, the part of a synchronous engine sits forms, whose stator 11 is arranged for the other side of the gap tubing pot 9 within the crankshaft housing 3.

The rotor 10 is composed of a rotor bundle of laminations, i.e. from a multiplicity one above the other stacked up transformer plates, which a central drilling 12 exhibits for the admission of the wave 8 as well as a multiplicity of extent-lateral recesses 13, which are formed from a circular recess formed close to the extent as well as a channel reaching up to the extent. The rotor bundle of laminations is, i.e. neighbouring in each case one above the other the arranged sheet metals are, related to which, around an angle recesses 13, that itself from Fig. 2 results in. In such a way formed rotor bundle of laminations is poured in the range of the recesses 13 with copper or a well leading copper alloy, so that the recesses 13 are completely filled. Beside the rotor or short-circuit staffs 14 educated by this capping finallaterally the rotor bundle of laminations stators 15 are intended, which the rotor staffs 14 kurzschließ EN and mechanically specify. These stators 15 are poured together with the rotor staffs 14, so that itself not only a well leading group between rotor staffs 14 and stators 15 results in, but at the same time a form-stable thing, which holds the rotor bundle of laminations together positively and firmly.

On the basis of Fig. 2 is represented, as this capping body formed made of copper or a copper alloy looks, if the rotor bundle of laminations is distant. It becomes clear that not only one very gleichmäß ige skew of the rotor staffs 14 and cross-setting of the rotor bundle of laminations is thus reached, but that by this cage-like thing an intimate group with the rotor bundle of laminations is created at the same time. The cavities formed by the recesses 13 in the rotor bundle of laminations are completely poured with copper or a copper alloy. To the comparison is in Fig. 4 a rotor after the state of the art represented, which is formed with conventionally imprinted copper rods. As this representation clarifies, recess 13 a gap is formed between rotor staff 14a and. This is necessarily on the one hand, in order to be able to imprint the rotor staffs 14a at all on the rotor bundle of laminations, and on the other hand, around this anschließ end still to be able. These free spaces are void with that erfindungsgemäß EN solution. Through cabinets of the rotor bundle of laminations within the range of neighbouring recesses of 13 formed sales in the form of steps completely by the capping material are filled out. Thus a high copper filling degree and a high magnetic conductivity and thus an improved efficiency are reached.

The gap tubing pot 9 is likewise formed for the improvement of the efficiency and the magnetic conductivity from a stainless, ferritic steel sheet, whose alloy composition was already indicated further above.

In order to protect the rotor bundle of laminations, the rotor staffs 14 and the stators 15 against contact with the liquid in the gap tubing pot 9, the rotor 10 is completely totally enclosed, i.e. with one after auß EN hermetically sealing sheet-steel jacket 16 provide. This sheet-steel jacket consists likewise of stainless, ferritic material, so that a high magnetic conductivity is ensured also here.

1 -

Electric motor

2 -

Centrifugal pump

3 -

Crankshaft housing

4 -

Pump housing

5 -

Gyroscope wheel

6 -

Intake

7 -

Printing connecting piece

8 -

Wave

9 -

Gap tubing pot

10 -

Rotor

11 -

Stator

12 -

Drilling

13 -

Recesses

14 -

Rotor staffs

14a -

Rotor staffs after the state of the art

15 -

Stators

16 -

Sheet-steel jacket