EP3309405A1 - Pump housing and liquid pump with pump housing - Google Patents

Abstract

The invention relates to a pump housing (2) for a liquid pump comprising a connecting portion (20) for connection to a motor housing, a housing chamber (21) in which an impeller (47) of a between the pump housing (2) and the motor housing (3) received Rotor unit (41) of a motor device (4) can be arranged, a coaxially to an ideal axis of rotation (I) of the impeller (47) arranged inlet nozzle (22), a transversely to the ideal axis of rotation (I) arranged drain pipe (23) and a spiral around the ideal axis of rotation (I) extending, in the outlet nozzle (23) opening out flow channel (24), wherein in the inlet nozzle (22) a flow rectifier (7, 107) is arranged, by means of which a through the inlet nozzle (22) flowing fluid flow in a plurality of separate, at least substantially linearly aligned partial streams can be divided. The invention further relates to a liquid pump (1) comprising a pump housing (2).

Description

AREA OF APPLICATION AND PRIOR ART

The invention relates to a pump housing for a liquid pump and a liquid pump comprising a pump housing, a motor housing connected to the pump housing and a motor device with a rotor unit received between the pump housing and the motor housing.

The liquid pump is, for example, a water pump, in particular a service water pump, a coolant pump, a pump for a solar fluid in a solar system or the like. In connection with the application, liquid pumps for conveying water or water mixtures, in particular a glycol-water mixture, are also generally referred to as water pumps.

Liquid pumps and associated pump housings are well known. It is for example off DE 202009017996 U1 a motor device with an electric motor designed as a spherical motor, wherein a rotor core or a rotor shell at least partially has a hemispherical shape or Kalottenform and is mounted spherically. Such pumps are also referred to as spherical motor pumps. The rotatably connected to the rotor core or the rotor shell impeller is arranged in a housing chamber of the pump housing, wherein a liquid is sucked in via a suction or inlet nozzle and conveyed away via a pressure or discharge nozzle.

TASK AND SOLUTION

It is the object of the invention to provide an improved pump housing for a liquid pump and an improved liquid pump comprising a pump housing.

This object is achieved by the pump housing and the pump having the features of claims 1, 10, 11 and 12.

According to a first aspect, a pump housing for a liquid pump, in particular a water pump or a pump for a glycol-water mixture is provided with a connecting portion for connection to a motor housing, with a housing chamber in which an impeller one between the pump housing and the Rotor housing accommodated rotor unit of a motor device can be arranged, with a coaxially arranged to an ideal axis of rotation of the impeller inlet nozzle, arranged with a transversely to the ideal axis of rotation drain pipe and with a spiral around the ideal axis of rotation extending into the outlet nozzle flow channel, wherein in the inlet nozzle a flow rectifier is arranged, by means of which a flowing through the inlet nozzle fluid stream into a plurality of separate, at least substantially linearly aligned partial streams is divisible.

The connecting portion has in one embodiment a thread for connection to the motor housing. In other embodiments, a flange connection is provided by means of connecting screws. In still other embodiments, the housing parts are inserted into each other. The connection is secured in one embodiment by means of a Schraubmanschette. Preferably, the motor housing is inserted into the pump housing, wherein the pump housing has an external thread for the Schraubmanschette.

The pump housing and the motor housing together serve to receive a motor device of the liquid pump, wherein the motor device has a rotor unit with an impeller. At least the impeller of the rotor unit is arranged in the housing chamber, so that upon rotation of the impeller, a liquid is sucked in via the suction or inlet nozzle and conveyed away via the pressure or discharge nozzle. According to the invention, a flow rectifier or flow laminator is arranged in the inlet connection.

The terms "flow straightener", "flow laminator" or "laminator" in the context of the application designate a fluidic device that greatly reduces turbulence in a flow and thus converts a turbulent flow into an at least largely laminar flow. The laminar flow also causes a better removal of trapped air in the liquid.

Through the flow straightener or laminator, the impeller is supplied with an at least substantially laminar flow. The laminar flow reduces pump losses and improves pump efficiency. This is particularly advantageous when using the pump housing with a designed as a spherical motor electric motor. In such an engine, the rotor unit performs a tumbling motion about an ideal axis of rotation, wherein by the flow straightener or laminator smoother running can be achieved. By the flow straightener or laminator and a rotation of a liquid column is prevented in the inlet nozzle. In addition, especially at Use in a pump for a mixture, for example a glycol-water mixture, prevents the mixture from foaming up and / or from forming air bubbles in the region of the inlet nozzle.

The direction of the ideal axis of rotation of the rotor unit is also referred to as the axial direction of the pump housing.

For stabilization or laminarization of the flow, various measures are known to those skilled in the art.

In one embodiment, the flow rectifier on a central hub and a plurality of radially projecting from the central hub fins. Preferably, the slats are arranged such that a division into several partial flows of the same size takes place. The hub itself is designed in one embodiment as a hollow tube or full tube with a circular cross-section. In other embodiments, a crossing point of the slats serves as a hub.

In an alternative embodiment, the flow straightener has a tube bundle structure, wherein tubes of the tube bundle structure each have a circular or polygonal, in particular hexagonal, cross section. The number, shape and size of the tubes can be selected depending on the application by the skilled person. Preferably, the tubes are arranged in a gap to avoid stagnation points in the fluid flow. The tubes of a flow rectifier preferably have the same cross sections for a subdivision into part streams of the same size.

In one embodiment, it is provided that the discharge nozzle protrudes radially from the intake manifold to a base body of the pump housing. With such a design, the inlet nozzle and the outlet nozzle lie in a common plane. This arrangement may be advantageous in particular with regard to installation of the pump housing in a line system.

In another, fluidically advantageous embodiment of the discharge nozzle protrudes tangentially to the inlet nozzle of the main body of the pump housing.

The helical flow channel may be appropriately shaped by those skilled in the art to optimize flow through the pump housing. In one embodiment, the spiral flow channel for this purpose has an oval cross-section. Alternatively or additionally, in other embodiments for this purpose in the spiral Flow channel is provided at least one guide for influencing the flow.

The pump housing is preferably made of plastic, in particular of polyamide (PA), polyphenylene ether (PPE) and / or PPE blend. The PPE blend is a mixture comprising PPE and at least one further polymer or copolymer, for example polystyrene, a styrene-butadiene copolymer and / or polyamide. In addition, a filler may be mixed in the plastic.

In a further embodiment, a central region of the flow rectifier protrudes from an outlet end of the inlet connection piece facing the rotor unit in the direction of the rotor unit.

According to a second aspect, there is provided a liquid pump including a pump housing, a motor housing connected to the pump housing, and a motor device having a rotor unit received between the pump housing and the motor housing, the pump housing having a connection portion for connection with a motor housing, a housing chamber in which an impeller the rotor unit is arranged, a coaxially arranged to an ideal axis of rotation of the impeller inlet nozzle, a transverse to the ideal axis of rotation arranged drain pipe and a spirally extending around the ideal axis of rotation, opening into the discharge nozzle flow channel, and wherein a flow rectifier is arranged in the inlet nozzle , by means of which a fluid stream flowing through the inlet nozzle can be subdivided into a plurality of separate, at least substantially linearly aligned partial streams.

The pump housing and / or the flow rectifier preferably have at least partially the features described above.

According to a third aspect, a liquid pump is provided comprising a pump housing and a motor housing connected to the pump housing, wherein a radial seal is arranged between the pump housing and the motor housing. The use of a radial seal instead of a conventional axial seal is particularly advantageous in a pump housing made of plastic, wherein a sealing surface can be provided with a high surface quality, on which rests, for example, designed as a sealing ring radial seal. By means of the radial seal a liquid-flow-through area of the pump is also possible if the pump housing and the motor housing are pressed against each other with little force, which for a Sealing by means of flat gaskets are not sufficient. The radial seal also permits relative movement of the pump housing and the motor housing about a longitudinal axis, for example for alignment of a cable outlet provided on the motor housing. The radial seal can be advantageously used both in combination with the flow rectifier and in a pump housing without flow straightener.

According to a third aspect, there is provided a fluid pump comprising a pump housing and a motor housing connected to the pump housing, wherein a connection of the pump housing to the motor housing is secured by means of a flanged cuff. The pump housing and the motor housing are screwed together, for example. In another embodiment, a housing part is inserted into the other housing part, wherein preferably the motor housing is inserted into the pump housing. After attaching a flanged collar separation of the motor housing of the pump housing is possible only with destruction or at least partial destruction of the sleeve. An unauthorized access to the pump housing and thus possibly associated contamination of the pumped liquid can be so difficult and at least visually detect. The sleeve can be advantageously used both in combination with the flow straightener and / or the radial seal and in a pump housing without flow straightener and / or radial seal.

According to an advantageous embodiment, the motor device of the liquid pump has a designed as a spherical motor electric motor, wherein a rotor core or a rotor shell at least partially has a hemispherical shape or Kalottenform and is mounted spherically. Such ball motors are characterized by a durable wear-free and robust operation.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1:

einen Ausschnitt einer Flüssigkeitspumpe mit einem Pumpengehäuse in einer geschnittenen Seitenansicht;

Fig. 2:

eine Draufsicht auf eine Vorderseite des Pumpengehäuses gemäß Fig.1;

Fig. 3:

eine perspektivische Darstellung einer Rückseite des Pumpengehäuses gemäß Fig.2;

Fig. 4:

eine perspektivische Darstellung der Vorderseite des Pumpengehäuses gemäß Fig.2;

Fig. 5:

eine Draufsicht auf einen Strömungsgleichrichter für ein Pumpengehäuse ähnlich Fig. 2 bis 4,

Fig. 6:

eine Draufsicht auf einen alternativen Strömungsgleichrichter für ein Pumpengehäuse ähnlich Fig. 2 bis 4 und

Fig. 7:

eine perspektivische Darstellung einer Vorderseite einer anderen Ausgestaltung eines Pumpengehäuses ähnlich Fig. 4.

Other advantages and aspects of the invention will become apparent from the claims and from the following description of preferred embodiments of the invention, which are explained below with reference to the figures. Here are shown schematically:

Fig. 1:

a detail of a liquid pump with a pump housing in a sectional side view;

Fig. 2:

a plan view of a front side of the pump housing according to Fig.1 ;

3:

a perspective view of a rear side of the pump housing according to Fig.2 ;

4:

a perspective view of the front of the pump housing according to Fig.2 ;

Fig. 5:

a plan view of a flow straightener for a pump housing similar Fig. 2 to 4 .

Fig. 6:

a plan view of an alternative flow straightener for a pump housing similar Fig. 2 to 4 and

Fig. 7:

a perspective view of a front side of another embodiment of a pump housing similar Fig. 4 ,

DETAILED DESCRIPTION OF THE EMBODIMENTS

Fig. 1 schematically shows a sectional side view of a detail of a liquid pump 1 with a pump housing 2, a connected to the pump housing 2 motor housing 3, and a partially illustrated motor device 4 with a recorded between the pump housing 2 and the motor housing 3 rotor unit 41. The pump housing 2 and the motor housing 3 are screwed together in one embodiment, wherein an internal thread is provided on a connecting portion 20 of the pump housing 2 for this purpose. In the illustrated embodiment, the motor housing 3 is inserted into the pump housing 2, wherein between the pump housing 2 and the motor housing 3 designed as a sealing ring radial seal 5 is arranged. For securing the connection, a flared collar 8 indicated schematically by a dashed line is provided, wherein a separation of the motor housing 3 from the pump housing 2 is possible only with destruction of the sleeve 8. The radial seal 5 allows a relative movement of the pump housing 2 and the motor housing 3 about a longitudinal axis, for example, for an orientation of a provided on the motor housing 3 cable outlet (not shown).

In another embodiment, a screw connection is provided, wherein an external thread is provided on the connecting portion 20 of the pump housing 2 for this purpose. In yet another embodiment, the connecting portion 20 of the pump housing 2 on locking elements for locking with the motor housing 3. The latching connection is designed in one embodiment such that a relative movement of the pump housing 2 and the motor housing 3 about a longitudinal axis at least in one limited area is possible. Even with a screw or a locking connection, a flanged sleeve 8 may be provided, which serves to secure the screw or locking connection of the motor housing 3 with the pump housing 2.

The liquid-conveying rotor unit 41 is sealingly separated by a partition 6 from a stator, not shown, of the motor device 4. The partition wall 6 is fastened in the exemplary embodiment to the engine housing 3 shown schematically. The rotor unit 41 comprises a support body 42 to which a rotor core 43 is fixed. The rotor core 43 is, for example, a permanent magnet. Due to the permanent magnetic stabilization forces can be dispensed with support elements. The rotor core 43 is sealed by a jacket 44 against the conveyed liquid. At edge regions of the casing 44, sealing elements, not shown, are preferably provided. The rotor unit 41 is rotatably mounted with a bearing cup 45 on a designed as a ball bearing, provided on the partition wall 6 sliding body 61, so that the rotor unit 41 can perform a tumbling motion about an ideal axis of rotation I. Between the casing 44 and the partition wall 6, a gap is formed, which allows the tumbling movement of the rotor unit 1.

Furthermore, the rotor unit 41 comprises an impeller 47 with blades 48.

The support body 42 and the impeller 47, the pump housing 2 and the motor housing 3 are each designed as plastic parts in the illustrated embodiment. The partition wall 6 and the sheath 44 are made as deep-drawn parts of a thermoformable, non-rusting material. For example, stainless steel, in particular a chromium-nickel steel, preferably a chromium-nickel-molybdenum steel, is used for the dividing wall 6 and the casing 44. In some embodiments, the partition wall 6 is at least partially further coated with an electrically insulating material.

That alone in the Fig. 2 to 4 illustrated pump housing 2 comprises a housing chamber 21, in which the impeller 47 of the rotor unit 41 is arranged, a coaxial with the ideal axis of rotation I of the impeller 47 arranged inlet nozzle 22, a discharge nozzle 23 and a spiral, opening into the outlet nozzle 23 flow channel 24th

The outlet pipe 23 is transversely, in particular perpendicular to the ideal axis of rotation I of the impeller 47 and thus arranged transversely to the inlet nozzle. As can be seen in the figures, the flow channel 24 extends in a spiral around the ideal axis of rotation I of the impeller 47th receiving housing chamber 21 in a direction away from the motor housing 3 direction to the discharge nozzle 23, wherein a cross section of the flow channel 24 increases continuously. At least at one end opening into the outlet nozzle 23, the flow channel 24, as in Fig. 1 recognizable, an oval cross-section on. At the outlet nozzle 23, a diffuser-like portion is provided, on which a widening of the outlet nozzle 23 takes place on a circular cross-section.

In the inlet nozzle 22, a flow rectifier 7 is arranged, by means of which a flowing through the inlet nozzle 22 fluid flow into a plurality of separate, at least substantially linearly aligned streams is subdivided.

In the illustrated embodiment, the flow straightener 7 has a central hub 70 a plurality of radially projecting from the central hub 70 fins 71. In the illustrated embodiment, four at an angle of 90 ° to each other arranged slats 71 are provided, so that a subdivision into four quarter-circular partial flows takes place. The hub 70 is designed as a solid material, so that no flow through the hub 70 itself takes place.

In the illustrated exemplary embodiment, the outlet connection 23 projects tangentially to the inlet connection 22 from a main body of the pump housing 2. The spiral flow channel 24 opens without further deflection in the outlet pipe 23. This arrangement is particularly advantageous for fluidic considerations. However, embodiments are also conceivable in which the outlet nozzle 23 protrudes radially to the inlet nozzle 22 from the main body of the pump housing 2 with a deflection of the fluid flow by approximately 90 °.

In the illustrated embodiment, a flow channel 24 is provided which is bounded by an outer housing wall and an inner wall concentric thereto laterally and by the partition wall 6 and a housing bottom up and down. In other embodiments, one or more fluidic guide means for influencing the flow through the flow channel 24 is provided.

FIGS. 5 and 6 schematically show plan views of two alternative design of a flow straightener 107. The flow straightener 107 according to the FIGS. 5 and 6 each have a tube bundle structure. In the embodiment according to Fig. 5 The tubes 72 of the tube bundle structure each have a circular cross-section. In the embodiment according to Fig. 6 the tubes 73 have a hexagonal cross-section. The number, size and shape of the tubes 72, 73 is merely exemplary. Except the illustrated Tube sections are other designs conceivable, preferably partial flows of the same size are created.

Fig. 7 shows a perspective view of a front side of another embodiment of a pump housing 2 similar Fig. 4 , wherein the same reference numerals are used for the same or similar components. In the inlet nozzle 22 of the pump housing 2 flow rectifier 7 is provided, which has a central hub 70 and a plurality of radially projecting from the central hub 70 fins 71. In the in Fig. 7 illustrated embodiment, a central region of the flow rectifier 7 adjacent to the hub 70 protrudes from one of the rotor unit 41 (see FIG Fig. 1 ) facing outlet end of the inlet nozzle 22 in the direction of the rotor unit 41 from.

At a rear side of the pump housing 2, two screw 26 are provided for attachment of the pump housing 2 and thus the liquid pump at an installation location.

It will be apparent to those skilled in the art that such screw 26 also on the pump housing 2 according to Fig. 2 to 4 may be provided or on screw channels 26 on the pump housing 2 according to Fig. 7 is waived.

Claims (13)

Pump housing for a liquid pump (1) comprising a connecting portion (20) for connection to a motor housing (3), a housing chamber (21) in which an impeller (47) of a between the pump housing (2) and the motor housing (3) received rotor unit (41) of a motor device (4) can be arranged, a coaxially to an ideal axis of rotation (I) of the impeller (47) arranged inlet nozzle (22), a transversely to the ideal axis of rotation (I) arranged discharge nozzle (23) and a spiral around the ideal axis of rotation (I) extending, in the outlet pipe (23) opening out flow channel (24), characterized in that in the inlet nozzle (22) a flow rectifier (7, 107) is arranged, by means of which a through the inlet nozzle (22) flowing Fluid flow into a plurality of separate, at least substantially linearly aligned streams is subdivided. Pump housing according to claim 1, characterized in that the flow rectifier (7) has a central hub (70) a plurality of, from the central hub (70) radially projecting fins (71). Pump housing according to claim 1, characterized in that the flow rectifier (107) has a tube bundle structure, wherein tubes (72) of the tube bundle structure each have a circular or polygonal, in particular hexagonal cross-section. Pump housing according to claim 1, 2 or 3, characterized in that the discharge nozzle (23) protrudes radially to the inlet nozzle (22) from a base body of the pump housing (2). Pump housing according to claim 1, 2 or 3, characterized in that the discharge nozzle (23) protrudes tangentially to the inlet nozzle of a main body of the pump housing (2). Pump housing according to one of claims 1 to 5, characterized in that the spiral flow channel (24) has an oval cross-section. Pump housing according to one of claims 1 to 6, characterized in that in the spiral flow channel (24) is provided at least one guide for influencing the flow. Pump housing according to one of claims 1 to 7, characterized in that the pump housing (2) made of plastic, in particular of polyamide (PA), polyphenylene ether (PPE) and / or PPE blend, is made. Pump housing according to one of claims 1 to 8, characterized in that a central region of the flow rectifier (7, 107) protrudes from one of the rotor unit (41) facing the outlet end of the inlet nozzle (22) in the direction of the rotor unit (41). Liquid pump comprising a pump housing (2), a motor housing (3) connected to the pump housing (2) and a motor device (4) having a rotor unit (41) accommodated between the pump housing (2) and the motor housing (3), the pump housing ( 2) a connecting portion (20) for connection to the motor housing (3), a housing chamber (21) in which an impeller (47) of the rotor unit (41) is arranged, coaxial with an ideal axis of rotation (I) of the impeller (47 ) arranged inlet connection (22), a transversely to the ideal axis of rotation (I) arranged drain port (23) and a spiral around the ideal axis of rotation (I) extending, in the outlet pipe (23) opening out flow channel (24), characterized in that a flow rectifier (7, 107) is arranged in the inlet connection (22), by means of which a fluid flow flowing through the inlet connection (22) into several, separate, at least substantially linear aligned sub-streams is divisible. Liquid pump according to claim 10 or according to the preamble of claim 10, characterized in that between the pump housing (2) and the motor housing (3) a radial seal (5) is arranged. Liquid pump according to claim 10 or 11 or according to the preamble of claim 10, characterized in that a connection of the pump housing (2) with the motor housing (3) by means of a flanged sleeve (8) is secured. Liquid pump according to claim 10, 11 or 12, characterized in that the motor device (4) has a designed as a spherical motor electric motor, wherein a rotor core (43) or a rotor shell at least partially has a hemispherical shape or Kalottenform and is mounted spherically.

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