EP2002126A2

EP2002126A2 - Rotary pump with coaxial magnetic coupling

Info

Publication number: EP2002126A2
Application number: EP07723756A
Authority: EP
Inventors: Werner Platt
Original assignee: H Wernert and Co OHG
Current assignee: H Wernert and Co OHG
Priority date: 2006-03-31
Filing date: 2007-03-29
Publication date: 2008-12-17
Anticipated expiration: 2027-03-29
Also published as: DE502007004191D1; DE202006005189U1; ATE449263T1; WO2007112938A2; KR101410628B1; ES2335946T3; ATE472060T1; EP1965081B1; CN101415950A; JP5461172B2; EP2002126B1; JP2009531589A; WO2007112938A3; DE502007002031D1; US8162630B2; CN101415950B; KR20080108150A; US20100028176A1; EP1965081A1

Abstract

A centrifugal pump has static and closed housing/walling (1) for the feed liquid within the pump, and a contactless permanent-magnetic coaxial rotary coupling (6,7;13,14) for transmission of a drive torque within the pump housing. A pump impeller (4) forms an open unit with a magnet rotor (6). Between the magnet rotor (6) and a magnet driver (13) is a partitioning wall facing the opening of the pump drive-face, and the magnet driver (13) is mounted in at least one rolling bearing (16a; 16b) adjoining the pump.

Description

Centrifugal pump with coaxial magnetic coupling

The invention relates to a centrifugal pump having the features of the preamble of claim 1, as known from EP-B1-0171515.

The centrifugal pumps with magnetic coupling represent an important type of industrially used machines for the conveyance of liquids. Compared to the simpler centrifugal pumps with mechanical seal they have the advantage of a hermetic seal of the pump chamber. This makes them especially favorable for the promotion of aggressive or toxic liquids.

In most cases executed coaxial rotary joints with radial arrangement of the magnets and corresponding radial magnetic action lines are used. Only this type is further considered below and is also the subject of the application.

The background of the invention is explained below with reference to Figures 1 to 4 to the known prior art solutions. Preliminary note 1: All drawings show an axial longitudinal section through the pump. The mostly cut rotational bodies were - with the exception of waves - for the sake of clarity without circumferential edges shown.

Preliminary note 2: For reasons of assembly and the various materials used, the component referred to below as the pump housing (1) must in practice be made up of several parts. Some of them are wetted by the liquid to be pumped and must be sealed accordingly, others not. For the sake of simplicity of illustration, the pump housing (1) is here shown in one piece.

A first known pump of conventional design is shown in Figure 1 and is e.g. advertised in the brochure [1].

In the pump housing (1 '), a rotating pump impeller (4') is arranged, which receives the liquid to be conveyed via the suction nozzle (2 ¹ ) and via the discharge nozzle (3 ') ejects again under pressure.

The radial bearing of the pump impeller (4 ') takes place by means of an impeller shaft (5') usually in plain bearings (9 ', 10'), the fixed parts in a bearing insert (11 ') are added. The lubrication and cooling of the sliding bearing (9 ', 10') takes place by the liquid to be pumped itself.

The axial bearing of the pump impeller (4 ') and the other associated and rotating parts is not considered here and in the following. It is only indicated here that in addition to a mechanical bearing with thrust washers also hydraulic principles of action based on pressure differences, as well as a magnetic bearing can come into question.

The part of the rotary coupling which receives the driving torque through a partition, which is usually designed as a thin-walled containment shell (12 '), therethrough and on the impeller shaft (5 ¹ ) to the pump impeller (4 ¹ ) passes, is referred to as a magnetic rotor (6 '). This is equipped with permanent magnets (7 '), which in turn must be surrounded before the corrosive and possibly also abrasive attack of the pumped liquid with a cylindrical protective jacket (8') liquid-tight. It should be mentioned only in passing that it may be necessary to protect an approximately metallic, that is to say ferromagnetically, magnet rotor (6 ') from corrosion as well as the shaft (5').

The part of the rotary coupling which receives and transmits the driving torque of the motor via the drive shaft (15 ') is commonly referred to as a magnet driver (13'). He is also equipped accordingly with permanent magnets (14 '), but rotate in air and therefore are not subject to any special attack. The radial and axial bearing of the magnetic drive takes place in commercial rolling bearings (16 ').

Another common embodiment, especially for smaller pumps, is shown in Figure 2. Such a pump is e.g. advertised in [2].

With this construction, a bearing insert (11 ') can be inexpensively eliminated. The pump impeller (4 ') is combined with the magnet rotor (6'), the permanent magnet (7 ¹ ) and the protective jacket (8 ') to a part. This rotating impeller magnetic rotor unit (19 ') is slidably mounted here on a fixed axle (17'). The axis (17 ') itself is fastened on one side via flow ribs (18') in the suction nozzle (2 '), supported on the other side in the specially shaped containment shell (12').

The design described in FIGS. 1 and 2 and largely conventional today (referred to here as design A) is characterized in that the magnet driver (13 ') is arranged radially outwardly beyond the magnet rotor (6') lying further inward. This construction has the advantage that the high mass moment of inertia of the outside magneto drive (13 ') counteracts the overly rapid start-up of the driving motor and thus the tearing off of the magnetic coupling can be prevented more favorably. Furthermore, this design facilitates, in particular, a generously axially spaced radial bearing of the pump impeller (4 ¹ ), which is always desirable due to the high hydraulic forces within the pump.

On the other hand, magnetic coupling pumps with a magnet rotor (6 ') located radially on the outside, which is in contact with the liquid, and an internal magnet driver (13') are less frequently used. This embodiment is referred to as type B.

Such type B pumps, e.g. in DE 01453760 or EP 0171514 or EP 0171515, and are shown in Figure 3, must be carefully designed so that during rapid startup, the magnetic coupling does not break off, which threatens here due to the outside magnetic rotor (6 '). Furthermore, the radially inner magnet driver (13 ') obstructs an axially pulled-out inner slide bearing of the impeller magnetic rotor unit (19'), if not the containment shell (12 '), with its actual opening in the type B drive side must be facing the pump, adversely wound right is executed. An executed pump of type B is advertised in [3] and served as a model for the figure 3. That in contrast to the construction according to Figure 2, the axis (17 ') is held exclusively by the flow ribs (18') has at the executed pump the advantage of a consistently thin-walled split pot (12 '), which is charged only with the internal pressure of the pump, but not by bearing forces. Similar to the pumps constructed in accordance with DE 01453760 or EP 0171514 according to US Pat. No. 5,501,582 A and DE 298 22 717 LH, although in addition to a direct radial bearing of the pump impeller, a slide bearing also exists on the outside of the magnet rotor, but this leads radially further internal bearing on the pump impeller to the known dry-running problems and a restriction of the pump impeller and high susceptibility to wear and unfavorable Gleichlaugeigenschaften the impeller magnetic rotor unit.

An important problem area in the operation of the previously presented magnetic pumps, which are thus provided with sliding bearings and the medium to be pumped even as their

Use cooling and lubricating medium, is the extensive or total absence even this liquid. Such a lack of lubrication occurs when higher gas fractions accumulate in the liquid, for example, by cavitation in front of the pump, Trombe entry or even in snore mode. These gas components accumulate in the radially inner cavities of the pump body due to the centrifugal action in the pump. In the conventional construction It. Figures 1 to 3 and according to US 5501582 A1 and DE 298 22 717 U1 but there are exactly the sliding bearings, which then fall dry and thereby often destroyed. Therefore, many proposals have been made to address this problem. However, these solutions often remain the tribology of the friction partners arrested - coupled with the attempt to reduce the friction of the bearing in case of deficient lubrication and thus to avoid the thermal destruction.

A technically different and very sensible way, namely to move the endangered plain bearing radially as far as possible to the outside, is provided by the solution approach of a "waveless" magnetic pump as described in [4], which is shown in Figure 4. This design is of the type It is possible here to arrive at a shaft- and axle-less construction by using as a fixed part (10 ') of the plain bearing a portion of the gap pot (12') and the rotating part (9 ') of the plain bearing through a portion of The pump impeller (4 ') is connected to the magnet rotor (6'), the permanent magnet (7 ¹ ) and the protective jacket (8 ') to a hollow impeller magnetic rotor unit (19 ') connected.

Nevertheless, the proposal from [4] remains technically limited. Thus, the radial slide bearing of the impeller magnetic rotor unit (19 ') takes place in the containment shell (12') itself, which, however, has to be executed at this point as a very thin-walled component. This is also pointed out in [4] and it is therefore not possible to dispense with more stable additional start-up or emergency bearings (37 ') which, disadvantageously, still partly have to be formed by the containment shell (12'). Furthermore, the support of the storage in thin-walled containment shell does not allow external cooling or easy external access, such as storage temperature monitoring or forced flushing. It should be noted that in the case of a malfunction, for example, cavitation before the pump, Trombeneintrag or snoring, a centrifugal pump is charged with significantly increased gas fractions in the liquid to be delivered. Due to the centrifugal effect in the pump, these gas fractions accumulate in the cavities of the pump body located radially inwards. In conventionally designed magnetic drive pumps there are the sliding bearings, which then fall dry and are therefore often destroyed.

Based on this, the present invention seeks to improve the radial bearing in the magnetic coupling of a generic centrifugal pump. To solve this problem, a centrifugal pump with the features of claims 1 or 3 is proposed.

The invention, which overcomes the prior art imperfections described above, and in which the radial bearing of the impeller magnetic rotor assembly is displaced outwardly as much as possible, et al. achieved the following advantages:

- The storage of the impeller magnetic rotor unit will continue to operate safely in the event of gaseintragen- the operating disturbance outside the vulnerable indoor area, and the spin-off of residual liquid to the outside, which then serves for bearing lubrication, is used to advantage;

- The storage is close to the outer housing wall, where by cooling ribs, the approximately heated, thrown off to the outside residual liquid can be effectively cooled;

- It is a comparatively high sliding speed achieved in the camps, so that the storage despite the usual low pump speeds (usually only 1000 1 / min to 3000 1 / min) even at low pumped medium viscosities

(often water-like) can reach the state of non-contact glide and thus the mixed friction region of conventional sliding bearings in magnetic coupling pumps is avoided;

- It is a simple external access to the bearings possible and thus the possibility of externally supplied bearing lubrication and / or a sensori- see monitoring of the camp created;

- The containment shell is no longer used as a supporting component, so that - subordinated to the transmission of magnetic moments - it can always be made thin-walled and nevertheless the risk of overloading and deformation does not exist;

- Furthermore, start-up and emergency camps are dispensable.

If the fixed part of the sliding bearing is arranged on the inside wall surface of the pump housing as a whole or is formed independently by the housing wall or sections of the housing wall of the pump housing, high radial bearing forces can be transmitted over a large axial length and a smooth synchronization of the impeller Magnetic rotor unit can be achieved. In the case of a plurality of axially spaced sliding bearing sections, these are preferably located approximately at the same radial level in order to further improve the running characteristics and the dry running capability of the bearing. Basically, it is within the meaning of the invention possible to store the pump impeller as such, in particular for receiving axial bearing forces. In addition, radial bearing forces can also be absorbed on the pump impeller, e.g. to improve the emergency running and / or starting characteristics. However, best synchronization conditions are achieved if the pump impeller can be rotated radially without contact or force.

If a liquid retaining space is provided in the region of the sliding bearing of the impeller magnetic rotor unit, thereby the risk of dry running is reduced). If the sliding bearing of the impeller magnetic rotor unit is carried out in its rotating part as a continuous sleeve, optionally in the form of a molding compound, thereby best possible material pairings and protection of the permanent magnets of the magnet rotor can be improved or simplified.

If the rotating part of the sliding bearing of the impeller magnetic rotor unit has recesses or elevations on its outer circumference, thereby the sliding properties improving liquid movements can be generated.

If the outside wall of the pump housing is provided in the region of the fixed part of the sliding bearing of the impeller magnetic rotor unit with cooling fins or a cooling jacket, overheating-related bearing damage can be avoided.

If accesses for external lubricants or monitoring sensors are provided in the wall of the pump housing in the region of the stationary part of the slide bearing of the impeller magnetic rotor unit, lubrication or emergency lubrication or wear control of this slide bearing can be achieved (FIG.

If the pump housing wall has a multilayer structure and the innermost material layer consists of a corrosion- or abrasion-resistant material, the longevity is improved even with difficult pumped media.

The above-mentioned embodiments of a centrifugal pump are also independent of claim 1 of independent inventive importance.

If the magnet driver has at least one bearing arranged in the region of the interior of the impeller / magnetic rotor unit, the pump length can be shortened considerably despite the fact that the magnet driver inside the pump is stored alone. For the magnetic drive bearing bearings are preferably used. The rolling bearing of the magnetic driver remains unaffected by the pumped liquid. For this is preferably used a ansich known, arranged between the magnet rotor and the magnet driver split pot. The magnet driver preferably has an open towards the drive side cup shape to receive the at least one bearing of the magnet rotor within the pump housing. A particularly advantageous mounting of the magnetic driver is achieved by a hollow hollow cantilever, through which the drive shaft of the magnet driver is guided, and which preferably carries on at least one inner or outer surface at least one of its end portions a bearing for the magnetic driver. Tapering in these end areas facilitate the placement of such bearings in a small space. If the tapering starts from the root of the cantilever, high bearing forces can be absorbed in a light construction.

The at least partial support of the magnetic driver within the space defined by the impeller magnetic rotor unit and the embodiments of such a bearing are of independent inventive significance.

The abovementioned and the claimed components to be used according to the invention described in the exemplary embodiments are not subject to special conditions in terms of their size, shape, material selection and technical design, so that the selection criteria known in the field of application can be used without restriction.

Further details, features and advantages of the subject of the invention will become apparent from the subclaims and from the following description of the accompanying drawing, in which - by way of example - a preferred embodiment of the inventive arrangement of a centrifugal pump is shown with coaxial magnetic coupling. In the drawing show:

5 shows a first embodiment of a centrifugal pump according to the invention in axial section - schematized; Fig. 6 shows a second embodiment;

Fig. 7 shows a third embodiment;

Fig. 8 shows a fourth embodiment;

9 shows a fifth embodiment;

10 shows a sixth embodiment;

11 shows a seventh embodiment;

Fig. 12 shows an eighth embodiment;

Fig. 13 shows a ninth embodiment;

14 shows a tenth embodiment as well

Fig. 15 shows an eleventh embodiment.

The embodiments have in common that they have a suction nozzle 2 and a discharge nozzle 3 exhibiting pump housing 1, wherein a pump impeller 4 is mounted coaxially to the suction nozzle and fluidly connected in the radial direction with the discharge nozzle 3. The pump impeller 4 has on the drive side a magnetic rotor 6, with which it forms an open to the drive side impeller magnetic rotor unit. This has on its outer circumference the rotating part 9 of a slide bearing, while the fixed part 10 of this sliding bearing is arranged on the inner wall 20 of the pump housing 1. The magnet rotor 6 carries permanent magnets 7 on the radially inner side. These stand opposite permanent magnets 14 at radial spacing, which are arranged on the outer surface of an approximately cup-shaped magnet driver 13. Between the magnet rotor and the magnet driver is In all embodiments, a partition wall, possibly in the form of a so-called split pot 12, interposed, which keeps dry the magnetic driver against the liquid wetted inside the pump. The magnet driver 13 is supported at two axially spaced locations via rolling bearings 16a and 16b. This storage takes place in all embodiments - although not mandatory - in each case with respect to the pump housing 1, wherein this storage takes place in the embodiments of Figures 7 to 15 at least pump side within the space formed by the impeller magnetic rotor unit 19. For this purpose, a continuous hollow cantilever 39 protrudes from the drive-side housing end wall toward the pump side and has a crawling design 39a, 39b, the drive shaft 15 of the pump passing through it being roller-mounted on its drive-side end region, while a second rolling bearing is mounted in the opposite end region on its outside, the drive shaft 15 indirectly, namely superimposed on the magnet driver 13. For this purpose, the latter has a pot shape which is open on the drive side.

The outer circumference of the impeller magnetic rotor unit 19 can now - with complete freedom of design and generous axial extent - be used to accommodate the rotating part 9 of the slide bearing (Figure 5, upper half) and does not need as in the prior art of Figure 4 be the most thin-walled protective jacket 8 for economic reasons. Again, this had led to the need for more radial startup and emergency bearings 37 in [4], which are no longer needed here in any way. It is even possible, with a suitable choice of the material and with appropriate shaping, that parts of the magnet rotor 6 itself can become the rotating part 9 of the slide bearing (FIG. 5, lower half). However, if the magnet rotor 6 is not suitable for this, since its material generally has to be ferromagnetic, then a suitable technical solution is offered with claims 3 and 4, as will be seen. This is subordinate to claim 1, since the introduced protection (sleeve 29 or molding compound 30) for the magnet rotor 6 ultimately also part of the impeller magnetic rotor unit 19 is. Since all parts of the coaxial magnetic coupling are located radially further inward, the fixed part 10 of the slide bearing can be easily brought directly to the stable inner housing 20 of the pump housing 1 (Figure 5, upper half) and no longer adversely affect the principle thin wall of Shutter 12, as described in [4]. It is even possible, with a suitable choice of material and with appropriate shaping, that parts of the housing wall 20 of the pump housing 1 itself can become the fixed part of the plain bearing 10 (Figure 5, lower half), possibly even by a multi-layered design as later set forth in claim 9.

For an effective slide bearing it is irrelevant whether it is mounted in two explicit bearing points 9, 10 a and 9, 10 b (FIG. 5, upper half), or whether the entire slide bearing is pulled apart to form a single axially extended "bearing drum" (FIG. 5) , bottom half). Combinations are also conceivable, ie explicit rotating bearing 9a and b against fixed bearing 10 as an axially extending drum and vice versa.

An arrangement according to claim 1 not only offers significant technological advantages, but also leads to an extremely simple construction of the entire pump.

In the case of a - in practice frequent - malfunction of the pump over massive gas entry (air or evaporated fluid in consequence cavitation), the residual liquid remaining in the pump will accumulate as a thrown off ring on the outer circumference in the pump housing 1. In a pump according to claim 1, the slide bearing 9, 10 is arranged exactly here, which can be operated as long as desired with the residual liquid with sufficient cooling. However, with very small residual amounts, which tend to occur at high delivery heights of the pump and low static counter-pressure, it can not be ruled out that these can escape axially in order to move to even higher radial levels in the impeller. This can be prevented via a lock in the form of a circulating ring 21, as the claim 2 introduces them and is shown in Figure 6. If the inner diameter of the circulation ring 21st chosen smaller than the contact diameter between the sliding bearing halves 9 and 10, the trapped and rotating liquid ring 23 will always wet the sliding bearing 9, 10 (Figure 6, upper half). Another advantage of this design results in the stoppage of the pump, namely, when the circulation ring 21 prevents complete emptying of the pump in the region of the sliding bearing 9, 10. If the pump is then restarted without a liquid is present at the suction nozzle 2, which is also a frequent operating error, then the slide bearing 9, 10 is still sufficiently lubricated with the liquid in the liquid retention chamber (22) remaining liquid template (Figure 6, lower half) and their axial escape during rotation also prevented by the lock.

The invention of claim 1 can also be exploited to shorten the axial extent of the pump considerably. This is possible because the magnetic driver 13 is not stored in the pump housing 1, but is placed directly on the shaft journal of the drive machine, that is to say ultimately stored by the drive machine. This is usually an electric motor. The electric motor is flanged directly to the pump, which is known as "block construction".

Advantage of this construction is in addition to the effect of axial shortening the savings of the two bearings 16. The disadvantage of this design is that the magnet driver 13 is no longer part of the pump and thus complete assembly of the pump can only be done if the driving motor present is. However, its size is initially at least in industrial pumps an unknown size and will be determined only on the basis of customer information. Thus, the time of final assembly of the pump is necessarily relocated behind this time and is also still an individual assembly with the known economic disadvantages.

Towards a better solution according to claim 10 (Figure 7) first, a preferably detachable, split pot 12 is introduced, as it always finds use in industrial pumps. In practice, these containment walls are designed with very thin walls on the circumference in order to be able to realize the smallest possible radial gap between magnet rotor 6 and magnet driver 13. Due to the design according to claim 1 For example, the containment shell 12 can be designed with a smooth end wall and must point with its larger opening in the direction of the drive side. Although the containment shell 12 should not itself be used to support a rolling bearing because of its thinness, it now offers sufficient space for an axially generously dimensioned rolling bearing 16 of the magnet driver 13 in its inner region 24 Baumass the pump are shortened to the conventional block design, but here the magnetic driver 13 is part of the pump, which allows a complete series assembly and stockpiling of the pump.

The shaft end 25 in such an axially shortened design can advantageously be carried out according to claim 15 or 16 (Figure 8) so that either via a conventional pump clutch (shown only the pin portion 27 of the pump clutch) the direct connection of a motor is possible (over an intermediate ring could also be flanged directly to the pump) or a shaft journal 28 again leads to the conventional pump with free shaft end (eg to comply with predetermined standard dimensions). Also, such a shaft end 25 should provide the opportunity to attach an additional flywheel 26 to compensate for the mentioned disadvantage of the type B chosen here when starting the pump can. All this would be part of the final assembly of the pump unit (which would also be carried out by the user of the pump itself) and would still allow a large-scale series assembly and cheap stockpiling of the pump at the manufacturer as described above.

The rotating part 9 of the plain bearing need not necessarily consist of two defined bearing sleeves a and b or from the magnet rotor 6 itself, but according to claim 3 (Figure 9) as an axially continuous sleeve 29 (Figure 9, upper half) or molding compound 30 (FIG. FIG. 9, lower half).

This offers economic advantages, in particular if these components according to claim 4 (FIG. 10) are also used for the protection and sealing of the radially lower one. NEN magnetic rotor 6 and the permanent magnets 7 serve. Namely, it is quite common, depending on the field of application of the pump, that the magnetic rotor 6 as ferromagnetic carrier of the permanent magnets 7 must be protected from the attack of the liquid to be conveyed and not in contact with the liquid like the pump impeller (4) may come. The now assumed difference of the materials between pump impeller (4) and magnet rotor 6 is expressed in a different hatching

The desired completely contact-free and thus wear-free and low-friction sliding of the impeller magnetic rotor system 19 in the pump housing 1 is opposed by the high peripheral speed of this arrangement. By additional dimple-like recesses or elevations on the surface of the rotating plain bearing 9, e.g. So on the sleeve 29 or the molding compound 30 so-called Taylor vortex in the sliding gap and in the adjacent rotational space of the liquid can be generated, which contribute to the stabilization and the contact freedom of the sliding bearing. These recesses or elevations are introduced with claim 5 (Figure 11).

In particular, if in the case of a malfunction in the pump only a liquid ring 23 rotates and a stream of fresh lubricant fails, this residual liquid will heat up in the plain bearing due to friction until a heat transfer equilibrium with the pump housing 1 is reached. Due to the direct contact of the slide bearing 9, 10 with the pump housing 1 is here by attaching outer fins 32, as introduced in claim 6 (Figure 12), a directly effective way increased convective heat dissipation drove and thus the reduction of stationary Temperature of the liquid ring 23 at a prolonged malfunction. In the upper half of Figure 12 is a Querverrippung shown in the lower longitudinal ribbing. This latter should be more useful in practice, since this can be used to advantage the already existing cooling air flow of the driving electric motor, which always takes place in the direction of the pump. In order to prevent the lack of lubrication of the sliding bearing 9, 10 even in the case of a corresponding malfunction, the supply of external lubricating fluid according to claim 7 (Figure 13) and / or a sensory monitoring (eg temperature, vibration, structure-borne noise) of the sliding bearing 9, 10 loud Claim 8 (Figure 14) proposed. Here, the proximity of the slide bearing 9, 10 to the pump housing 1 acts so that this access can be done very easily.

Many designed magnetic coupling pumps, which are particularly suitable for conveying aggressive, abrasive and hazardous liquids due to the hermetic seal of the pump interior are lined in the wetted area of the pump housing 1 with about a plastic layer or from several - usually two - constructed material shells. Ultimately, then the innermost layer of material 35 must have the desired properties with respect to the liquid, while the outer shells serve more the shape and stability to the internal pressure of the pump. Claim 9 (FIG. 15) also makes this construction method valid for the present invention. Since in particular the mentioned plastic materials (eg PTFE or PE) can be used very well as a sliding bearing material in mixed friction region, a construction is proposed, as shown in Figure 15 in the lower half. If, on the other hand, the material of the innermost material layer 35 is not suitable for plain bearings, the design in the upper half of FIG. 15 must be used.

LIST OF REFERENCE NUMBERS

1 pump housing

2 suction nozzles 3 discharge nozzles

4 pump impeller

5 impeller shaft

6 magnet rotor

7 Permanent magnet (rotor) 8 Protective jacket

9 rotating plain bearing

9a rotating plain bearing, impeller side

9b rotating plain bearing, drive side

10 fixed slide bearing 10a fixed plain bearing, impeller side

10b fixed plain bearing, drive side

11 bearing insert

12 split pot

13 magnetic driver 14 permanent magnet (driver)

15 drive shaft

16a rolling bearing, impeller side

16a roller bearing, drive side

17 axis 18 flow ribs

19 impeller magnetic rotor unit

20 Inside wall of the pump housing

21 circular ring

22 liquid retaining space 23 rotating amount of residual liquid

24 Interior of the containment shell 25 shaft ends

26 flywheel

27 Spigot part of a pump clutch

28 shaft journals

29 sleeve

30 molding compound

31 recesses

32 cooling fins

33 Access for lubricating fluid

34 Access for sensors

35 innermost material layer

36 sealant

37 starting or emergency storage

38 outer circumference of the impeller magnetic rotor system

39 cantilever

39a rejuvenation

39b rejuvenation

LITERATURE

[1]

Brochure of

Company WERNERT-PUMPEN GMBH D-45476 Mülheim an der Ruhr

Standardized Plastic Chemical Pump with Magnetic Coupling - NM Series Edition 687/02

[2] Brochure of

Company IWAKI pumps Iwaki Magnetic Pumps - MDM printed series in Japan 99.11. ITN

[3] Brochure of

Company CP-Pumpen AG CH-4800 Zofingen: Magnetic coupling pump MKP, metallic

[4]

Robert Neumaier:

Hermetic pumps

Publisher and Picture Archive W.H. Faragallah, 1994

ISBN-3-929682-05-2 Chapter 3.7.12 Magnetic Centrifugal Centrifugal Pumps

P. 356 ff

Claims

1st centrifugal pump

- With a static and closed enclosure of the pumped liquid inside the pump in the form of a housing (1),

with a non-contact, permanent magnet coaxial rotary coupling (6, 7, 13, 14) for transmitting a drive torque into the interior of the pump housing

with a pump impeller (4) which, together with a, permanent magnets (7) supporting, magnetic rotor (6) forms a slide-bearing, open to the drive side, cup-shaped structural unit (impeller magnetic rotor unit 19),

and in which the magnetic lines of action of the driving part of the rotary joint (magnetic driver 13 and permanent magnets 14) point radially outwards and the magnetic lines of action of the pump impeller (4) connected to the part of the rotary joint (magnet rotor 6 and permanent magnets 7) point radially inwards .

characterized in that for the radial mounting of the impeller magnetic rotor unit (19)

the rotating part (9; 9a, 9b) of a plain bearing is arranged along the outer circumference (38) of the magnet rotor (6) and fixedly connected thereto or through the outer circumference or sections of the outer circumference (38) of the magnet rotor (6) itself is formed.

2. Centrifugal pump according to claim 1, characterized in that the fixed part (10; 10a ₁ 1Ob) of the slide bearing on the inside wall surface (20) of the pump housing (1) is arranged or through the housing wall or portions of the housing wall (20) of the pump housing ( 1) itself is formed.

3. Centrifugal pump, in particular according to claim 1 or 2, in which a plurality of axially spaced sliding bearing sections (9a, 10a, 9b, 10b) are provided, these are located at approximately the same radial level.

4. Centrifugal pump according to one of claims 1 to 3, characterized in that the pump impeller (4) is radially contact or forcibly rotatable.

5. Centrifugal pump according to one of claims 1 to 4, characterized in that between the pump impeller (4) and the sliding bearing (9, 10) a circumferential ring (21) or collar is arranged so that its inner dimension is smaller as the contact diameter of the sliding bearing (9, 10) and thereby a liquid retaining space (22) in the region of the plain bearing (9, 10) both during rotation and at standstill of the pump impeller (4) is obtained.

6. Centrifugal pump, in particular according to one of claims 1 to 5, characterized in that the rotating part (9; 9a, 9b) of the slide bearing is designed as an axially continuous sleeve (29) or axially continuous cast or pressed molding compound (30).

7 rotary pump according to claim 6, characterized in that the sleeve (29) or the molding compound (30) are applied, shaped or sealed with sealing means (36) or are that they are part of a protective jacket (8) for the permanent magnets (7). and / or the magnet rotor (6).

8. Centrifugal pump, in particular according to one of claims 1 to 7, characterized in that the rotating part (9; 9a, 9b) of the sliding bearing at its Outer circumference with a plurality of local recesses (31) or elevations is provided, which favor the formation of stabilizing flow vortexes in the sliding bearing.

9 centrifugal pump, in particular according to one of claims 1 to 8, characterized in that the outside wall of the pump housing (1) in the region of the fixed part (10) of the slide bearing with cooling fins (32) is provided.

10 centrifugal pump, in particular according to one of claims 1 to 9, characterized in that the fixed part (10) of the slide bearing can be supplied by one or more accesses (33) in the wall of the pump housing (1) with external lubricant.

Centrifugal pump 11, characterized ^'in particular according to one of claims 1 to 10, that the fixed part (10) can be monitored by sensors of the plain bearings through one or more entrances (34) in the wall of the pump housing (1).

12. Centrifugal pump according to one of claims 1 to 11, characterized in that the wall of the pump housing (1) is constructed of a plurality of material layers and the innermost material layer (35) consists of a corrosion and / or abrasionsbeständigem material.

13. Centrifugal pump according to the preamble of claim 1, in particular according to one of claims 1 to 12, wherein between the magnet rotor (6) and magnet driver (13) a partition wall is arranged, which faces with its opening of the drive side of the pump and the liquid inside the pump from the magnetic driver (13) separates, characterized in that the magnet driver (13) is mounted in at least one bearing connected to the pump, such as a roller bearing (16),

that at least one impeller-side bearing, such as a rolling bearing (16a), in the inner region (24) of the pump housing is located and

the storage of the magnetic driver (13) takes place without contact with the partition wall.

14. Centrifugal pump according to claim 13, characterized in that the at least one impeller-side bearing is located in the inner region of an internally hollow magnet friction (13).

15. Centrifugal pump according to claim 13 or 14, characterized in that the impeller-side bearing of the inner ring is fixed and the associated outer ring with the mounted magnetic driver (13) rotates.

16. Centrifugal pump according to claim 15, characterized in that a drive-side bearing, such as roller bearings (16b) is provided, whose inner ring rotates with the stored drive shaft (15) and the associated outer ring is fixed.

17. Centrifugal pump according to one of claims 13 to 16, characterized in that a continuous hollow, in the pump housing (1) from the drive side protruding Kragzapfen (39) for receiving the drive shaft (15) provided vorge and connected to the pump housing or connectable is.

18. Centrifugal pump according to claim 17, characterized in that the hollow cantilever (39) has a taper (39a, 39b) at least in one of its end regions.

19. Centrifugal pump according to one of claims 13 to 18, characterized in that the region of the drive-side end (25) of the drive shaft (15) is designed so that it has a flywheel (26) or is providable.

20. Centrifugal pump according to one of claims 13 to 19, characterized in that the region of the drive-side end (25) of the drive shaft (15) is designed such that it optionally with a flywheel (26), a pin member (27) of a pump clutch and / or a shaft journal (28) is releasably connectable.

21. Centrifugal pump according to one of claims 13 to 20, characterized in that the magnet driver (13) has an open towards the drive side pot shape.