Pump with electric drive motor and stator cooling

Abstract

A pump for conveying a fluid comprises a pumping housing (1, 4) with an inlet (2) and an outlet (3) for the fluid, a pumping impeller (15) rotatable in the pumping housing (1, 4) for conveying the fluid, and an electric drive motor with a rotor (10) coupled to the pumping impeller (15) for its drive, and a stator (20) forming a running gap (14) around the motor axis (R) with the rotor (10). The stator (20) comprises a stator core (21, 22, 23) with stator teeth (21) and tooth gaps remaining between the stator teeth (21), electrical conductors wound around the stator teeth (21) to form electrical coils (25), a primary insulation (26) formed for electrical insulation between the respective stator tooth (21) and the coil (25) surrounding the respective stator tooth (21), and a secondary insulation (28) formed for electrical insulation of adjacent coils (25) in the tooth gaps.

Description

[0001] The invention relates to a pump driven by an electric drive motor for conveying a fluid, preferably a liquid. The fluid to be conveyed can be, for example, a cooling fluid and / or a lubricating fluid for cooling and / or lubricating one or more components of a traction drive system of a motor vehicle. The pump can, in particular, be a cooling and / or lubricating fluid pump for a motor vehicle and may, for example, serve to cool a primary battery and / or to cool and / or lubricate an electric traction motor of a purely electric vehicle or a hybrid vehicle, or to cool and / or lubricate an internal combustion engine of a hybrid vehicle or a purely internal combustion engine-powered vehicle.

[0002] Electrically driven pumps, predominantly centrifugal pumps, are increasingly used to circulate cooling fluids in motor vehicles. The electric drive motors used for this purpose are currently mostly electronically commutated, i.e., brushless, direct current motors (BLDC motors), which are generally operated at 12, 25, or 48 V. These integrated or pump-integrated electric motors can be designed as either wet or dry-running pumps. In dry-running pumps, the electric motor is usually mounted on roller bearings, with the fluid-contacting part of the pump sealed against the electric motor by a shaft seal, such as a mechanical seal or a lip seal.Due to the large and expensive rolling bearings, the significant costs of the technically sophisticated shaft seal, the comparatively complex cooling concepts for the electric motor, and the control board integrated into the pump, for example, into the motor housing, dry-running pumps are not very common in automotive coolant pumps. In wet-running pumps, at least parts of the electric motor, such as the rotor and the rotor bearings, are wetted by the pumped medium.

[0003] DE 10 2021 133 484 A1 discloses a fluid pump with an integrated electric drive motor through which the fluid being pumped can flow for cooling. The drive motor comprises a stator with a stator core wound with electrical conductors to form electrical coils. Before winding, the stator core is overmolded with a primary insulation layer, and after winding and contacting, it is additionally overmolded with a secondary insulation layer, so that the overmolding forms a canned tube. The overmolding has axially parallel, groove-shaped cooling channels on the outer and / or inner circumference of the stator and recesses formed circumferentially between the cooling channels, which correspond to the cooling channels in such a way that the stator laminations exposed within the recesses can be cooled by the fluid.

[0004] One objective of the invention is to realize a compact and cost-effective pump with an electric drive motor with high overall efficiency and effective cooling.

[0005] The pump should advantageously be suitable for use in a motor vehicle and for pumping a cooling and / or lubricating fluid.

[0006] A desirable electric drive motor for a pump is compact, has a high overall efficiency, and can be effectively cooled by means of fluid.

[0007] One task can also be seen as the creation of a compact and powerful, yet inexpensive, electrically driven pump.

[0008] The invention relates to a pump for conveying a fluid, for example, a cooling and / or lubricating fluid. The fluid can be a gas or, in particular, a liquid. The pump comprises a pump housing with an inlet and an outlet for the fluid, an impeller rotatable about an axis of rotation within the pump housing for conveying the fluid, and an electric drive motor for the impeller. The drive motor comprises a stator and a rotor rotatable about a motor axis relative to the stator and the pump housing, which is coupled to the impeller for rotary drive of the impeller. The stator surrounds the rotor and forms a running gap extending about the motor axis with the rotor. The stator has a stator core with stator teeth extending at least substantially radially to the motor axis and electrical coils wound on the stator teeth.To electrically isolate the coils from the stator core, the stator includes a primary insulation layer that surrounds each stator tooth and is formed between the tooth and the coil surrounding it. A secondary insulation layer, located in the gaps between adjacent stator teeth, provides electrical isolation between neighboring coils.

[0009] The stator core can advantageously be a laminated core with axially stacked stator laminations. Designing the stator core as a laminated core facilitates variation of the axial length of the stator core by varying the number of stacked stator laminations, thereby allowing the torque generated by the drive motor to be varied according to the application. The drive motor can thus be easily and flexibly adapted to the torque requirements of the application without changing its fundamental design.

[0010] According to a first aspect of the invention, the stator teeth are free of both primary and secondary insulation at their tooth ends, which face the rotor radially across the running gap. The stator teeth may be coated with a thin layer of lacquer at their tooth ends radially opposite the rotor. Preferably, however, they are free of any material application at least on the circumferential surface facing the rotor in the region of the tooth ends. By leaving the tooth ends of the stator teeth neither covered by the insulating material of the primary nor by the insulating material of the secondary insulation on their circumferential surface facing the rotor, which is hereinafter also referred to as the running surface, a running gap with a small radial running gap width can be achieved.The smaller the radial gap width, the lower the losses in magnetic flux density across the gap. This allows for smaller coils while maintaining the same power output, thus reducing the amount of material used in the coil windings. In this way, it is possible to create a powerful, energy-efficient, yet compact and cost-effective, and therefore competitive, drive motor.

[0011] Since the stator teeth are free of the insulating material of the first and second layers on their radially adjacent running surface, which defines the running gap, they can be directly exposed to the flow of cooling fluid within the running gap. The cooling effect is further intensified if the metal of the stator tooth is exposed on the radially adjacent running surface. If the stator core is designed as a laminated core, cooling fluid from the running gap can also penetrate between the stator laminations and effectively cool the stator core from the inside.

[0012] In advantageous embodiments, the running gap between the rotor and stator, measured radially to the axis of rotation, has a radial gap width that is smaller than the average thickness of the primary insulation. If the primary insulation covers the stator core, preferably in a skin-like manner, the radial running gap width in such embodiments is smaller than the thickness of this "skin." It is advantageous that the running gap can have a radial gap width that only accommodates the component and positional tolerances as well as the bearing clearances of the drive motor, in order to prevent the running surface of the respective stator tooth from coming into contact with the opposite running surface of the rotor during pump operation.

[0013] To effectively cool the drive motor, given the high power density achievable through the reduced gap width, a cooling channel through which cooling fluid flows extends axially through the secondary insulation in one or more of the tooth gaps, according to a second aspect of the invention. Advantageously, one cooling channel through which cooling fluid flows extends axially through the secondary insulation in each of the tooth gaps. Two or more cooling channels through which cooling fluid flows can extend axially through the secondary insulation in one or more of the tooth gaps. Preferably, however, only a single such cooling channel extends in each tooth gap. Advantageously, the secondary insulation surrounds the respective cooling channel continuously along its entire axial length. The circumferential wall of the respective cooling channel can be formed by a tubular insert embedded in the secondary insulation.Preferably, however, the secondary insulation, i.e., the insulating material from which the secondary insulation is formed, directly forms the channel wall. The respective cooling channel can, in particular, be formed as a straight axial passage and / or open onto axially opposite end faces of the secondary insulation.

[0014] It is advantageous if the cooling channel has a cross-section along its entire length that is at least half the cross-sectional area of ​​the tooth gap measured between adjacent coils. The closer the cooling fluid is to the stator core and / or the coils as it flows through the cooling channel, the more effectively the heat is dissipated from the stator core and / or the coils.

[0015] During pump operation, the stator can be cooled from the rotor gap and the stator's internal cooling channels. The combination of rotor gap cooling and cooling channel cooling enables more intensive and therefore more effective cooling of both the stator and the rotor, which benefits directly from the rotor gap cooling and indirectly from the cooling channel cooling via the stator. Compared to either method individually, the cooling fluid can flow through the drive motor at a higher rate. The total heat exchange surface area available for convection is larger, offering greater scope for optimization. Furthermore, the coils are cooled internally via the stator teeth and the advantageously thermally conductive primary insulation, and externally via the secondary insulation, also advantageously thermally conductive, through the tooth gaps.It should also be noted that, in advantageous embodiments, the pump is designed so that, during pump operation, both the flow gap and the cooling channels are permeated by a cooling fluid. The fluid pumped by the impeller can, in particular, serve as the cooling fluid.

[0016] The primary insulation shields the coils from the stator core and the cooling fluid that penetrates between the stator laminations when the core is designed as a laminated core. The secondary insulation shields the coils at the stator ends from the outside and, in conjunction with the primary insulation, serves to shield them from the cooling fluid that flows through the gap in advantageous designs. Advantageously, the primary and secondary insulation together enclose the coils and shield them from the ingress of cooling fluid. The respective insulation material should be an electrical insulator but is also advantageously a good thermal conductor.

[0017] The primary and secondary insulation layers are connected fluid-tight, i.e., impermeable to the fluid, at least in the region of the tooth ends around the respective stator tooth. This fluid-tight connection can be based on a material bond. For example, the primary and secondary insulation layers can be materially bonded, at least in the region of the tooth ends, in a ring-shaped joining zone surrounding the respective stator tooth, impermeable to the fluid. This bonding zone can be, for example, glued or preferably fused together. The joining zone formed around the respective stator tooth in the region of the tooth end, if such a special joining zone exists, extends between the running surface and the coil of the stator tooth.

[0018] To ensure a tight seal with increased reliability, the primary and secondary insulation layers can feature one or more interlocking joining geometries in the region of the tooth ends, extending continuously around the respective stator tooth. These geometries interlock and, when engaged, form an annular joining zone that is impermeable to the fluid. The respective joining geometry can be a protrusion or recess circumferentially around the respective stator tooth. Alternatively, the primary and secondary insulation layers can form a joining zone extending annularly around the respective stator tooth in the region of the tooth ends. In this zone, a microstructure of the primary insulation layer and a microstructure of the secondary insulation layer interlock to a greater depth than at the base of the tooth gaps. The depth of engagement is measured on the circumference of the respective stator tooth perpendicular to the circumferential surface of the stator tooth in contact with the primary insulation layer.In advantageous designs, the initial insulation surrounds the respective stator tooth like a skin. The depth of the procedure is therefore measured orthogonally to this "skin".

[0019] The one or more joining geometries of the primary insulation and the one or more joining geometries of the secondary insulation can interlock by positive and / or frictional engagement, creating the required seal. Preferably, they are bonded in the annular joining zone, for example, by adhesive bonding or, advantageously, by fusing together. If they are only fused near the surface, the joining geometries still engage even after fusing, although the geometries may be deformed by the melting process compared to their shape before fusing. If the joining geometries are completely melted, the annular joining zone may exhibit a molten microstructure formed during the fusing process.If the primary and secondary insulation layers are made of the same material and the respective joining geometries are completely fused, the joining zone formed at each tooth end may only be characterized by the fact that no transition is discernible between the primary and secondary insulation layers. However, in such designs, a transition may still be discernible outside the annular joining zone, radially further away from the running gap, and / or at the base of the tooth gaps. In principle, the primary and secondary insulation layers can also be completely fused together, without any discernible transition, either partially or entirely, outside of the special joining zones maintained at the tooth ends.

[0020] In advantageous embodiments, the primary insulation is formed from an electrically insulating first plastic and the secondary insulation from an electrically insulating second plastic, and fused together in the region of the tooth ends in a joining zone extending annularly around the respective stator tooth, as discussed above. The first plastic and the second plastic can form a fused or mixed structure in the annular joining zone. If the primary and secondary insulation are also fused together outside the annular joining zone, for example at the base of the tooth gaps, the mixed structure in the annular joining zone has a greater depth than a fused or mixed structure at the base of the tooth gaps.The greater depth can be achieved by having the first insulation layer, prior to the production of the second insulation layer, have one or more joining geometries in the area of ​​the subsequent annular joining zone, for example, one or more projections circumferentially around the respective stator tooth and / or one or more recesses circumferentially around the respective stator tooth. Advantageously, the first insulation layer is formed with one or more projections circumferentially around the respective stator tooth.

[0021] If the secondary insulation is preferably injection-molded, the primary insulation can be partially or completely melted during overmolding, particularly in the area of ​​the respective joining geometry. This results in a particularly strong material bond between the first and second plastics in the annular joining zone. The respective joining geometry, which is exposed in the molten secondary insulation at the beginning of the overmolding process, has a large heat-conducting surface area relative to its mass. Therefore, compared to a smooth surface of the primary insulation, the joining geometry melts and / or completely melts rapidly, and after cooling, a fluid-tight, material-bonded connection between the primary and secondary insulations is formed.

[0022] The first and second plastics may be identical in terms of material, so that the designations "first plastic" and "second plastic" refer only to the point of production. Alternatively, the first and second plastics may differ with respect to the polymer material. If the first and / or second plastic has a polymer matrix and one or more fillers within that matrix, the first and second plastics may differ with respect to the material of the polymer matrix and / or with respect to one or more of the fillers.If the two plastics differ from each other in a polymer component and / or a filler and the joining geometries in the respective joining zone are completely fused together, the melt structure of the joining zone has a smaller concentration gradient with respect to this polymer component and / or with respect to this filler than at the base of the tooth gaps.

[0023] Both thermoplastics and thermosets are suitable plastics. The insulation layers can be either thermoplastic or thermoset. In principle, a thermoset primary insulation layer can be combined with a thermoplastic secondary insulation layer, or vice versa.

[0024] The primary and secondary insulation layers together enclose the coils in advantageous configurations to electrically insulate them from each other, from the stator core, and thus from the fluid in the engine compartment. The primary insulation can extend beyond the coils and surround the stator teeth towards the tooth ends. It can completely enclose the stator core up to the tooth ends, for example, in a skin-like manner, so that only the tooth ends are free of the primary insulation, at least on their running surface that defines the contact gap. The secondary insulation can enclose the stator core and the coils, so that only the tooth ends are free of the secondary insulation, at least on their running surface, with connection elements for the electrical connection of the coils passing through the secondary insulation.

[0025] In a first variant, the primary insulation encases the stator core up to the running surfaces of the stator teeth, and the secondary insulation fills the gaps between the teeth up to the running surfaces of the stator teeth, so that the running surfaces of the stator teeth and the insulation material in the gaps are flush. This minimizes turbulence of the cooling fluid in the gap. In a second variant, the insulation material in the gaps is set back radially slightly behind the running surfaces, leaving the running surfaces radially exposed. In the first variant, the running surfaces of the stator core and the insulation material in the gaps advantageously form a smooth, circular cylindrical running surface of the stator.In the second variant, the exposed running surfaces of the stator core advantageously form a circular cylindrical running surface of the stator that projects beyond the tooth gaps towards the rotor.

[0026] The rotor of the drive motor and the impeller can be arranged coaxially and rotatably about their common axis of rotation. The rotor and the drive motor are coupled by means of a drive shaft for torque transmission. Preferably, they are fixedly connected to the drive shaft. The drive shaft can advantageously be a hollow shaft.

[0027] To cool the drive motor, a cooling path for the cooling fluid can extend from a cooling path inlet to and through the running gap and / or to and through the respective cooling channel of the stator and further to a cooling path outlet. The cooling path inlet and the cooling path outlet can open into a main flow of fluid, which can be conveyed by the impeller, in order to divert fluid from the main flow for cooling the drive motor and return it through the motor compartment to the main flow. Advantageously, the cooling path inlet is arranged in a region of higher pressure and the cooling path outlet in a region of lower pressure within the main flow, such that a pressure differential exists between the cooling path inlet and the cooling path outlet during pump operation, which alone is sufficient as the driving force to convey the fluid along the cooling path through the motor compartment.

[0028] The cooling path inlet and / or outlet can each open into the pump housing to divert fluid for cooling the drive motor within the pump from the main flow and / or return it to the main flow. Thus, the cooling path inlet can open into a fluid region of higher pressure within the pump housing, and / or the cooling path outlet can open into a fluid region of lower pressure within the pump housing. The cooling path inlet can open into the pumping chamber, for example, downstream of the impeller in the region of the outlet or between the impeller and the outlet. The cooling path outlet can advantageously open upstream of the impeller in the region of the inlet or, in particular, on the front of the impeller towards the inlet.

[0029] The cooling path can branch between the higher-pressure region and the lower-pressure region into a first path leading through the running gap and a second path leading through the respective cooling channel of the stator. It can branch into the two paths downstream of the cooling path inlet. Preferably, it branches further in the higher-pressure region by providing a first cooling path inlet and, separately, a second cooling path inlet, with fluid flowing through the first cooling path inlet to the running gap and through the second cooling path inlet to the cooling channels of the stator.

[0030] The two cooling paths can merge in the low-pressure region. Preferably, they merge within the engine compartment downstream of the running gap and the cooling channels, so that the fluid is discharged from the engine compartment via the cooling path outlet common to both paths and preferably returned to the main flow. If the drive shaft is a hollow shaft, the fluid can advantageously be returned via the drive shaft. In this case, the drive shaft or the impeller can form the cooling path outlet.

[0031] In advantageous designs, the secondary insulation surrounds the wound stator core around its outer circumference. Beyond its function as a mere enclosure, it can advantageously be extended to form a motor housing. The conveyor housing can be directly connected to this motor housing, for example, by means of a screw connection.

[0032] The secondary insulation can form a terminal housing for one or more electrical connection elements, through which the drive motor can be connected to an external power supply and / or control system. The terminal housing can be designed for a plug connection with a correspondingly shaped terminal. The respective connection element can be embedded in the secondary insulation and thus positioned and fixed relative to the motor housing and the terminal housing. The electrical connection element can therefore have an inner contact, an outer contact, and a connecting section that links the inner contact to the outer contact. The connecting section can be embedded within the secondary insulation. The inner contact can protrude from the secondary insulation for the electrical connection of motor electronics.The outer connection contact can protrude from the secondary insulation in the connection housing for electrical connection to the external system.

[0033] Beyond its function as an enclosure, the secondary insulation can advantageously be further developed into a rotary bearing structure for the rotational support of the rotor. The secondary insulation and the rotary bearing structure are advantageously formed in one piece, for example, as a plastic casting. The rotary bearing structure can have one or more passages. The cooling path described above can extend upstream or downstream of the running gap through the respective passage of the rotary bearing structure.

[0034] Motor electronics, comprising a circuit board and electronic components for power supply and control of the drive motor, can be an integral part of the pump. The secondary insulation can be formed with joining elements that engage with the circuit board, fixing the board relative to the stator. These joining elements can, for example, protrude pin-like from the rear of the stator facing away from the impeller and extend through the circuit board. Alternatively, the joining elements can form connecting rivets, so that the circuit board is joined to the stator by means of a rivet connection, such as a hot rivet connection.

[0035] The secondary insulation is advantageously formed in one piece using a primary forming process, for example as a plastic casting. With regard to the additional functionality described above, this means that the secondary insulation can advantageously be formed in the primary forming process together with a motor housing surrounding the stator core and / or together with a connection housing for the electrical connection to an external system for power supply and / or control of the drive motor and / or together with a rotary bearing structure for the radial support of a drive shaft that is non-rotatably connected to the rotor and / or the impeller.

[0036] The additional functionalities of the secondary insulation can advantageously be implemented individually and more advantageously in any combination. Each of the additional functionalities can be implemented without feature 1.8, i.e., the primary insulation and / or the secondary insulation can also cover the running surface of the stator. Likewise, each of the additional functionalities can be implemented without feature 1.9, i.e., the stator has no cooling channels of the type according to the invention or has no channels for fluid at all. On the other hand, each of the additional functionalities can be implemented with feature 1.8 or instead with feature 1.9 of claim 1, i.e., without the other feature, or preferably with both features 1.8 and 1.9 of claim 1.

[0037] The pump can be designed, for example, as a centrifugal pump, particularly a radial centrifugal pump, and the impeller can be a radial impeller. The drive motor can be an external rotor, with the rotor surrounding the stator, so that the stator's running surface is an outer circumferential surface. Preferably, however, the drive motor is an internal rotor, and the stator surrounds the rotor, so that the stator's running surface is an inner circumferential surface. The rotor is preferably equipped with permanent magnets, but can alternatively be provided with electrical coils. In principle, the configuration can also be reversed, so that only the rotor is equipped with electrical coils and the stator with permanent magnets. In such designs, the permanent magnets replace the stator coils. The additional cooling achievable via the stator's cooling channels, in addition to the cooling of the rotor gap, is also advantageous for such modifications.The cooling channels can then, for example, extend axially through the stator between the permanent magnets of the stator.

[0038] The pump can be specifically designed for use as a cooling media pump for conveying a water / glycol mixture and / or a dielectric heat transfer oil for cooling or temperature control of one or more components of a motor-driven vehicle, such as a motor vehicle. More specifically, in such a use, it can be configured for temperature control. - of an internal combustion engine and / or - of powertrain components of an internal combustion engine vehicle powertrain and / or - components of the powertrain of a battery electric vehicle and / or - the battery cells of a motor vehicle traction battery. "For temperature control" means that the pump is designed for cooling only, heating only, or, depending on demand, for both cooling and heating. In particular, the pump can be configured as a cooling medium pump for circulating a dielectric heat transfer oil for temperature control by direct heat exchange, i.e., for direct cooling and / or direct heating, of the battery cells of a motor vehicle traction battery.

[0039] In advantageous versions, the pump is designed for variable speed control by a vehicle control unit or engine control unit and can be controlled by the vehicle control unit or engine control unit depending on one or more measured variables, such as the outside temperature and / or the temperature of a vehicle component to be cooled.

[0040] The invention also relates to a method for manufacturing a stator for an electric drive motor, preferably the stator for the drive motor of the pump disclosed herein. The method comprises at least the following steps: A stator core, which has stator teeth with free tooth ends pointing at least substantially radially to a motor axis and gaps remaining between the stator teeth, is overmolded with an electrically insulating first layer of plastic to form a primary insulation that surrounds the stator teeth and preferably lines the gaps. This can also be referred to as primary overmolding. - Electrical conductors are wound around the stator teeth, which have been provided with initial insulation, to form electrical coils. The stator core and coils are overmolded with a second, electrically insulating plastic to form a secondary insulation layer that extends beyond the coils to the tooth ends. This can also be referred to as secondary overmolding. - During the injection molding of the secondary insulation, cooling channels extending axially through the secondary insulation are formed in the area of ​​the tooth gaps to allow the passage of a fluid used for cooling the stator. - At the tooth ends, the stator has circumferential or running surfaces to form a running gap with the rotor of the drive motor. These running surfaces are free of the primary and secondary insulation. For this purpose, the running surfaces can initially be overmolded with the plastic of the primary insulation during the initial overmolding and / or with the plastic of the secondary insulation during the secondary overmolding, and the respective plastic can then be removed from the running surfaces in a post-processing step. Advantageously, however, both the initial and secondary overmolding are carried out in such a way that the running surfaces remain free of the respective plastic during both the initial and secondary overmolding processes.

[0041] Advantageously, the primary insulation in the area of ​​the tooth ends is injection-molded with one or more joining geometries circumferential to the respective stator tooth in the form of one or more protrusions and / or recesses. During the injection molding of the secondary insulation, the respective joining geometry is partially or fully melted in contact with the second plastic, so that, in the case of partial melting, the respective joining geometry engages with the secondary insulation after cooling, or, in the case of full melting with the first plastic, forms a microscopically mixed structure.

[0042] Features of the invention are also described in the aspects formulated below. These aspects are formulated in the manner of claims and can replace them. Features disclosed in the aspects can further supplement and / or qualify the claims, show alternatives to individual features, and / or extend claim features. Reference numerals in parentheses refer to embodiments of the invention illustrated in the figures below. They do not restrict the features described in the aspects to their literal meaning as such, but rather indicate preferred ways of realizing the respective feature. 1. Pump for conveying a fluid, for example a cooling fluid and / or a lubricating fluid, the pump comprising: a. a conveying housing (1, 4) with an inlet (2) and an outlet (3) for the fluid, b. a rotating conveyor wheel (15) in the conveying housing (1, 4) for conveying the fluid from the inlet (2) to the outlet (3), and c. an electric drive motor with a rotor (10) rotatable about a motor axis (R), which is coupled to the conveyor wheel (15) for its drive, and a stator (20) which forms a running gap (14) about the motor axis (R) with the rotor (10), the stator (20) comprising: d. a stator core (21, 22, 23) with stator teeth (21) pointing at least substantially radially to the motor axis (R) and tooth gaps remaining between the stator teeth (21), e. electrical conductors wound around the stator teeth (21) to form electrical coils (25), f. a primary insulation (26) which is formed for electrical insulation between the respective stator tooth (21) and the coil (25) surrounding the respective stator tooth (21), g. and a secondary insulation (28) formed in the tooth gaps for electrical insulation of adjacent coils (25), h. wherein the stator teeth (21) each have a running surface (24) at tooth ends (23) which faces radially towards the rotor (10) via the running gap (14) and is optionally free from the primary insulation (26) and / or the secondary insulation (28), i. and / or in one or more of the tooth gaps, optionally a cooling channel (29) through which coolant flows in an axial direction extends through the secondary insulation (28). 2. Pump according to the preceding aspect, wherein the first insulation (26) and the second insulation (28) are connected in a manner that is impermeable to the fluid at least in the area of ​​the tooth ends (23) around the respective stator tooth (21), preferably by a material bond, so that the coils (25) are separated from the running gap. 3. Pump according to the preceding aspect, wherein the first insulation (26) and the second insulation (28) are joined in a materially bonded manner, preferably fused, at least in the area of ​​the tooth ends (23) in a ring-shaped joining zone circumferentially around the respective stator tooth (21). 4. Pump according to one of the preceding aspects, wherein the primary insulation (26) surrounds the stator teeth (22) in the area of ​​the coils (25), preferably lining the tooth gaps up to almost the tooth ends (23), and is in a ring-shaped joining zone around the respective stator tooth (21) that is impermeable to the fluid, for example by fusing, to the secondary insulation (28). 5. Pump according to one of the preceding aspects, wherein the first insulation (26) and the second insulation (28) in the region of the tooth end (23) of the respective stator tooth (21) have one or more joining geometries (27) circumferential around the respective stator tooth (21) which interlock to form an annular joining zone impermeable to the fluid when engaged. 6. Pump according to one of the preceding aspects, wherein the primary insulation (26) and the secondary insulation (27) in the region of the tooth end (23) of the respective stator tooth (21) have one or more projections (27) circumferential around the respective stator tooth (21) and correspondingly one or more recesses which interlock to form an annular joining zone impermeable to the fluid when engaged. 7. Pump according to one of the preceding aspects, wherein the first insulation (26) and the second insulation (28) form a ring-shaped joining zone around the respective stator tooth (21) in the region of the tooth end (23) of the respective stator tooth (21), in which they are fused together with an increased surface contact compared to a joining area located at the base of the respective tooth gap. 8. Pump according to one of the preceding aspects, wherein the first insulation (26) and the second insulation (28) in the area of ​​the tooth ends (23) form a joining zone extending in a ring shape around the respective stator tooth (21), in which a microstructure of the first insulation (26) and a microstructure of the second insulation (28) interlock deeper than at the base of the tooth gaps. 9. Pump according to one of the preceding aspects, wherein - the first insulation (26) consists of a first plastic and the second insulation (28) consists of a second plastic, - the first insulation (26) and the second insulation (28) in the area of ​​the tooth ends (23) are fused in a joining zone extending in a ring shape around the respective stator tooth (21) and - a mixed structure formed from the first plastic and the second plastic has a greater depth (d) in the ring-shaped joining zone than at the base of the tooth gaps. 10. Pump according to the preceding aspect, wherein the first plastic and the second plastic differ with respect to a polymeric component and / or with respect to a filler. 11. Pump according to one of the preceding aspects, wherein the first insulation (26) and the second insulation (28) together enclose the coils (25) and electrically insulate them from each other and from the stator core (21, 22, 23). 12. Pump according to one of the preceding aspects, wherein the first insulation (26) lines the tooth gaps of the stator core (21, 22, 23). 13. Pump according to one of the preceding aspects, wherein the stator (20) has a stator yoke (22) extending in an annular shape around the axis of rotation (R), from which the stator teeth (21) project, and the primary insulation (26) covers the circumference of the stator yoke (22) facing away from the stator teeth (21). 14. Pump according to one of the preceding aspects, wherein the first insulation (26) completely encloses the stator core (21, 22, 23) up to the tooth ends (23), so that only the tooth ends (23) are free from the first insulation (26) at least on their running surface (24) which limits the running gap (14). 15. Pump according to one of the preceding aspects, wherein the secondary insulation (28) encloses the stator core (21, 22, 23) and the coils (25), such that only the tooth ends (23) are free from the secondary insulation (28) at least on their running surface (24) limiting the running gap (14), and connecting leads (25a) for the coils (25) pass through the secondary insulation (28). 16. Pump according to one of the preceding aspects, wherein the secondary insulation (28) fills the tooth gaps of the stator core (21, 22, 23) between the adjacent coils (25) around the respective cooling channel (29). 17. Pump according to one of the preceding aspects, wherein the secondary insulation (28) directly surrounds the respective cooling channel (29) so that it directly forms the circumferential wall of the respective cooling channel (29). 18. Pump according to one of the preceding aspects, wherein the respective cooling channel (29) is an axially extending passage, preferably a straight axial passage, through the secondary insulation (28). 19. Pump according to one of the preceding aspects, wherein a cooling path for the fluid extends from a cooling path inlet (4a, 4b) opening into the pump housing (1, 4) in a region of higher pressure, through the running gap (14) and / or the respective cooling channel (29) to a cooling path outlet (16a) opening into the pump housing (1, 4) in a region of lower pressure. 20. Pump according to the preceding aspect, wherein the cooling path between the area of ​​higher pressure and the area of ​​lower pressure branches into a first path which passes through the running gap (14) and a second path which passes through the respective cooling channel (29). 21. Pump according to one of the two immediately preceding aspects, comprising a drive shaft (16) which couples the rotor (10) of the drive motor to the impeller (15) for the transmission of torque, wherein the cooling path extends in the axial direction through the drive shaft (16). 22. Pump according to the preceding aspect, wherein the drive shaft (16) forms the cooling path outlet (16a). 23. Pump according to one of the preceding aspects, wherein the rotor (10) of the drive motor and the impeller (15) are arranged coaxially and rotatably about the common axis of rotation (R). 24. Pump according to one of the preceding aspects, wherein the rotor (10) of the drive motor and the impeller (15) are connected in a non-rotatable manner. 25. Pump according to one of the preceding aspects, wherein - the conveying wheel (15) is arranged in a conveying chamber and the drive motor (10, 20) is arranged in a motor compartment and are coupled by means of a drive shaft (15) for the transmission of torque, - the conveying housing (1, 4) has a rear wall (4) on an end face axially facing the engine compartment, and - the drive shaft (16) protrudes through this rear wall (4). 26. Pump according to one of the preceding aspects, wherein the rotor (10) of the drive motor and the impeller (15) are arranged coaxially along a drive shaft (16) rotatable about the axis of rotation (R), which is preferably formed as a hollow shaft. 27. Pump according to the preceding aspect, wherein the rotor (10) of the drive motor and the impeller (15) are each connected to the drive shaft (16) in a non-rotatable manner. 28. Pump according to one of the preceding aspects, wherein the secondary insulation (28) completely encloses the stator core (21, 22, 23) and the coils (25) up to the tooth ends (23), so that of the stator core (21, 22, 23) only the tooth ends (23) are free from the secondary insulation (28) at least on their running surface (24) which limits the running gap (14). 29. Pump according to one of the preceding aspects, wherein the secondary insulation (28) forms a motor housing (6). 30. Pump according to one of the preceding aspects, comprising a motor housing (6) that completely encloses the stator core (21, 22, 23) and the coils (25) up to the tooth ends (23), so that only the tooth ends (23) remain free at least on their running surface (24) which limits the running gap (14). 31. Pump according to the preceding aspect, wherein the secondary insulation (28) forms the motor housing (6). 32. Pump according to one of the preceding aspects, wherein the secondary insulation (28) is formed in a single piece using a primary forming process, for example as a plastic casting. 33. Pump according to one of the preceding aspects, wherein the secondary insulation (28) is formed in one piece, for example as a casting made of plastic, together with a motor housing (6) surrounding the stator core (21, 22, 23) and / or together with a connection housing (7) for electrical connection to an external system for power supply and / or control of the drive motor (10, 20) and / or together with a rotary bearing structure (8) for radially supporting a drive shaft (16) non-rotatably connected to the rotor (10) and / or the impeller (15). 34. Pump according to the preceding aspect, wherein the motor housing (6) comprises one or more joining elements (6a) formed by the primary forming process for joining with the pump housing (1, 4) and / or joining elements (6b) formed by the primary forming process for joining with a circuit board (33) of motor electronics equipped with electronic components (34). 35. Pump according to one of the two immediately preceding aspects, wherein the rotary bearing structure (8) comprises a central bearing structure surrounding the drive shaft (16) and a radially extending connecting beam supporting the central bearing structure on the stator (20). 36. Pump according to one of the preceding aspects, wherein the secondary insulation (28) forms a motor housing (6) and the pump housing (1, 4) is directly joined to the motor housing (6), preferably directly to the secondary insulation (28), for example by means of a screw connection (6a, 9). 37. Pump according to one of the preceding aspects, wherein the secondary insulation (28) forms a terminal housing (7) for one or more electrical connection elements (42, 46) and the stator (20) can be connected to an external power supply and / or control system via the terminal housing (7) and the respective connection element (42, 46), for example by means of a plug connector connection. 38. Pump according to the preceding aspect in combination with one of aspects 29, 30, 33, 36 and 37, wherein the respective electrical connection element (42, 46) is embedded in the secondary insulation (28) and is thereby positioned and fixed relative to the motor housing (6) and / or the connection housing (7). 39. Pump according to the preceding aspect, wherein the respective electrical connection element (42, 46) has an inner connection contact (43), an outer connection contact (45) and a connecting section (44) that connects the inner connection contact (43) to the outer connection contact (45), and wherein the connecting section (44) is embedded in the secondary insulation (28), the inner connection contact (43) protrudes from the secondary insulation (28) for the electrical connection of a motor electronics (34), and the outer connection contact (45) protrudes from the secondary insulation (28) for the electrical connection to the external system in the terminal housing (7). 40. Pump according to one of the preceding aspects, comprising a rotary bearing structure (8) for rotary bearing of the rotor (10), wherein the secondary insulation (28) and the rotary bearing structure (8) are formed in one piece by primary forming, for example as an injection molded part made of plastic. 41. Pump according to the preceding aspect in combination with aspect 19, wherein the cooling path extends upstream or downstream of the running gap (14) through one or more passages (8a) of the rotary bearing structure (8). 42. Pump according to one of the preceding aspects in combination with aspects 19 and 25, wherein the cooling path extends upstream of the running gap (14) and / or the respective cooling channel (29) through the rear wall (4) of the pump housing (1, 4). 43. Pump according to one of the preceding aspects in combination with aspect 19 and one of aspects 21, 25, 26 and 33, wherein the cooling path extends downstream of the running gap (14) through the drive shaft (16). 44. Pump according to one of the preceding aspects, comprising motor electronics with a circuit board (33) and electronic components (34) arranged thereon for power supply and control of the drive motor (10, 20), wherein the secondary insulation (28) is formed with joining elements (6b) which are in joining engagement with the circuit board (33) and fix the circuit board (33) relative to the stator (20) by the joining engagement. 45. Pump according to the preceding aspect, wherein the joining elements (6b) protrude in a pin-like manner from a rear side of the stator (20) facing away from the impeller (15) and penetrate the circuit board (33). 46. ​​Pump according to one of the two immediately preceding aspects, wherein the joining elements (6b) form connecting rivets, so that the circuit board (33) is joined to the stator (20) by means of a rivet connection, for example a hot rivet connection. 47. Pump according to one of the preceding aspects in combination with one of aspects 29, 30, 33 and 36, comprising: - a front wall (30) that closes off the motor housing (6) at one end, and - a circuit board (33) with motor electronics (34) for controlling and / or supplying power to the stator (20), - wherein the circuit board (33) is arranged on an end face of the end wall (33) facing axially away from the stator (20). 48. Pump according to the preceding aspect, wherein the motor housing (6) has joining elements (6b) which are integrally formed on the motor housing (6) and which project through the end wall (30) and the circuit board (33) and form connecting rivets, so that the end wall (30) and the circuit board (34) are joined to the motor housing (6) by means of a rivet connection, for example a hot rivet connection. 49. Pump according to one of the preceding aspects, wherein the impeller (15) is a radial impeller. 50. Pump according to one of the preceding aspects, wherein the pumping casing (1, 4) forms a pumping chamber spirally shaped around the axis of rotation (R) of the pumping wheel (15). 51. Pump according to one of the preceding aspects, wherein the inlet (2) of the pump housing (1, 4) directs the fluid coaxially to the axis of rotation (R) to the pump impeller (15). 52. Pump according to one of the preceding aspects, wherein the stator (20) surrounds the rotor (10). 53. Pump according to one of the preceding aspects, wherein the running gap (14) has a radial running gap width w, which is measured radially to the axis of rotation (R) between the running surface (24) of one of the stator teeth (23) and a circumference of the rotor (10) opposite the running gap (14), and the first insulation (26) in the region of the tooth ends (23) has a thickness D, wherein w < D or w < 0.5·D. 54. Pump according to one of the preceding aspects, wherein - the first insulation (26) and the second insulation (28) in the area of ​​the tooth gaps are radially behind the running surfaces (24) of the stator teeth (23) or instead - the first insulation (26) and the second insulation (28) in the area of ​​the tooth gaps are flush with the running surfaces (24) of the stator teeth (23). 55. Pump according to one of the preceding aspects, which is used as a cooling media pump for conveying a water / glycol mixture and / or a dielectric heat transfer oil for cooling or temperature control (cooling and / or heating) - of an internal combustion engine and / or - of powertrain components of an internal combustion engine vehicle powertrain and / or - components of the powertrain of a battery electric vehicle and / or - is designed for the battery cells of a traction battery of a motor vehicle. 56. Pump according to one of the preceding aspects, designed as a cooling media pump for conveying a dielectric heat transfer oil for direct cooling (cooling / tempering) of the battery cells of a traction battery of a motor vehicle. 57. Pump according to one of the preceding aspects, designed for variable speed control by a vehicle control unit or engine control unit and controlled by the vehicle control unit or engine control unit depending on one or more measured variables, such as the outside temperature and / or a temperature of a vehicle component to be cooled. 58. Method for manufacturing a stator for an electric drive motor, preferably the stator (20) for the drive motor of the pump according to one of the preceding aspects, comprising the following steps: a. A stator core (21, 22, 23) having stator teeth (21) pointing at least substantially radially to a motor axis (R) with free tooth ends (23) and tooth gaps remaining between the stator teeth (21) is overmolded with an electrically insulating first plastic to form a first insulation (26) which surrounds the stator teeth (21) and preferably lines the tooth gaps, b. electrical conductors are wound around the stator teeth (21) provided with the primary insulation (26) to form electrical coils (25), c. the stator core (21, 22, 23) and the coils (25) are overmolded with an electrically insulating second plastic to form a secondary insulation (28) which encloses the coils (25) and the stator core (21, 22, 23) beyond the coils (25) to the tooth ends (23), and d. During the injection molding of the secondary insulation (28), cooling channels (29) extending axially through the secondary insulation (28) are formed in the area of ​​the tooth gaps for the passage of a fluid serving to cool the stator, e. wherein at the tooth ends (23) a running surface (24) to form a running gap (14) with a rotor (10) of the drive motor is free from the first insulation (26) and the second insulation (28). 59. Method according to the preceding aspect, wherein the first insulation (26) and the second insulation (28) are injected such that the running surface (24) remains free of the first plastic and free of the second plastic during injection molding. 60. Method according to one of the two immediately preceding aspects, wherein the first insulation (26) in the area of ​​the tooth ends (23) is injection molded with one or more joining geometries (27) circumferential around the respective stator tooth (21) in the form of one or more projections and / or depressions (27), and the respective joining geometry (27) is melted or fused to the second plastic during injection molding of the second insulation (28), so that the respective joining geometry (27) engages in the second insulation (28) in the case of fusion or forms a microscopically mixed structure with the first plastic in the case of fusion. 61. Method according to one of the three immediately preceding aspects, wherein the first plastic and the second plastic differ with respect to a polymeric component and / or with respect to a filler.

[0043] An embodiment of the invention is explained below with reference to the figures. Features that become apparent in the embodiment, both individually and in each combination of features, advantageously further define the subject matter of the claims and aspects, as well as the further embodiments described above. The figures show: Fig. 1. A pump according to the invention is shown in an isometric exploded view of a front side and in an isometric exploded view of a back side of the components of the pump; Fig. 2 the pump in a first longitudinal section; Fig. 3 the pump in a second longitudinal section; Fig. 4 the pump in a cross-section; Fig. 5 a detail of the Fig. 4; Fig. 6 a stator core wound with coils of an electric drive motor of the pump; Fig. 7 a detail of the Fig. 6; Fig. 8 a stator of the drive motor in an isometric view of the front of the stator; Fig. 9. Place the stator in an isometric view on the back; Fig. 10 the stator in an isometric exploded view; Fig. 11 the stator with electrical connection elements detached from the assembly; and Fig. 12 a joining connection for fixing a circuit board populated with electronic components.

[0044] Fig. Figure 1 shows a pump according to the invention in two exploded views: the top isometric view of a front view and the bottom isometric view of a rear view of the pump components. The pump is functionally divided into a conveying section with an impeller 15, a drive section with an electric drive motor comprising a rotor 10 and a stator 20, and an electronics section with a circuit board 33 and electronic components 34 for supplying and controlling the drive motor 10, 20. These functional sections are arranged one after the other along a motor shaft of the drive motor 10, 20 within a multi-part housing.

[0045] The pumping section comprises a pump housing with a housing part 1 and a back wall 4, which, in the assembled state of the pump, separates the pumping section from the drive section. The housing part 1 has an inlet 2 and an outlet 3 for a fluid to be pumped. The housing part 1 and the back wall 4 together enclose a pumping chamber that connects the inlet 2 to the outlet 3. A ring seal 5 ensures a fluid-tight connection between the housing part 1 and the back wall 4 in the assembled state. The housing part 1 itself can be made of several parts, but is preferably formed in a single piece. The impeller 15 is rotatably mounted in the pumping chamber so that, when driven by the drive motor 10, 20, it pumps the fluid from the inlet 2 into and through the pumping chamber to the outlet 3.

[0046] The pump is designed as a radial centrifugal pump. Accordingly, the impeller 15 is a radial impeller and the pumping chamber is a spiral chamber. The inlet 2 guides the fluid axially into the pumping chamber, while the outlet 3 discharges the fluid tangentially. Alternatively, the pump can also be designed as a positive displacement pump, for example, as an internal displacement pump such as a vane pump or gear pump. However, the centrifugal pump design is preferred, particularly for applications as a cooling fluid pump.

[0047] The drive section comprises a motor housing 6, which surrounds the stator 20 and is rigidly connected to it. A terminal housing 7 is integrally formed with the motor housing 6. The terminal housing 7 contains electrical connection contacts for connecting the drive motor, in this embodiment the stator 20, to an external power supply and / or an external control system, for example, to the engine control unit of a motor vehicle. The terminal housing 7 surrounds the connection contacts and, together with the motor housing, is designed for a plug connection with a corresponding plug terminal.

[0048] In its assembled state, the pump houses the rotor 10 in a motor compartment enclosed by the motor housing 6. The rear wall 4 separates the motor compartment from the pumping chamber. The drive motor 10, 20 is designed as an internal rotor motor. The rotor 10 is thus enclosed by the stator 20. A drive shaft 16 is rigidly connected to the rotor 10. The drive shaft 16 forms the motor shaft of the drive motor 10, 20. A bearing bushing 17 and a bearing washer 18 provide rotary support for the drive shaft 16 and thus also for the rotor 10. A ring seal 19 provides a sealing function between the rotor 10 and the bearing washer 18 in the assembled state.

[0049] An end wall 30 closes off the motor compartment at its rear, facing axially away from the conveying section. The end wall 30 serves as a partition between the motor compartment and an electronics compartment, in which electronic components 34, visible in the lower illustration, are arranged on the circuit board 33. A ring seal 31, arranged between the motor housing 6 and the end wall 30, ensures a fluid-tight separation of the electronics compartment from the motor compartment. A foil-like gap filler 32 is provided between the end wall 30 and the circuit board 33. In the assembled state, the disc-shaped end wall 30, the foil-like gap filler 32, and the circuit board 33 form an axial layered structure. A cover 35 closes off the electronics compartment at its rear.

[0050] In the assembled state, the conveyor housing 1, 4 and the motor housing 6 lie axially against each other and are rigidly joined. They are joined, for example, by means of a screw connection. To create the joint, the conveyor housing 1, 4 is provided with joining elements 1a and the motor housing 6 with joining elements 6a, which are rigidly joined relative to each other by means of joining elements 9, for example, screw elements. The joining elements 1a are straight axial passages formed in the housing part 1. The joining elements 6a are axial recesses or passages formed on the motor housing 6 corresponding to the joining elements 1a. If the joining elements 9 are designed as screw elements, as in the exemplary embodiment, the joining elements 6a can be provided with matching internal threads. Advantageously, the joining elements 9 cut into the joining elements 6a, thus ensuring a secure hold of the conveyor housing 1 on the motor housing 6.

[0051] The layered assembly consisting of end wall 30, gap filler 32 and circuit board 33 is immovably joined to the motor housing 6, for example by means of a screw connection or preferably by means of a connection described below and in Fig. 12 recognizable rivet-like connections. After arranging and fastening the layer structure 30, 32, 33, and thus in particular the circuit board 33, the electronics compartment is closed by means of the cover 35. The cover 35 can advantageously be joined to the motor housing 6 by a material bond, for example by means of a friction weld.

[0052] A mounting structure 37 is provided for mounting the pump, for example, in the engine compartment of a vehicle powered by an internal combustion engine, a purely electric vehicle, or a combined internal combustion engine and electric vehicle. The mounting structure 37 can advantageously be connected to the pump via a damper 36. In the exemplary embodiment, the damper 36 is designed as a damping ring, for example, an elastomer ring. The damper 36 is placed around the outer circumference of the motor housing 6 and can then advantageously surround the motor housing 6 with a certain elastic tension. In such embodiments, the damper 36 is adapted to the outer circumference of the motor housing 6 with a certain undersize with respect to its inner circumference. The mounting structure 37 forms a sleeve.It comprises two parts movable relative to each other, in the exemplary embodiment two hemispherical structural parts, which are attached to the outside of the damper 36 from the side and tightened with suitable fastening means, for example screws, with a certain tension in order to mount the motor housing 6 and thus the pump itself over the damper 36 at the installation location. The mounting structure 37 can have one or more joining elements 38 by means of which the mounting structure 37 and thus the pump can be fastened at the installation location, for example in an engine compartment of a motor vehicle.

[0053] Fig. Figure 2 shows the assembled pump in a central longitudinal section, in which the axis of rotation R of the drive shaft 16 and the rotor 10 extends. The spiral-shaped pumping chamber, which connects the central axial inlet 2 with the tangential outlet 3, is visible. The pumping chamber is closed off at its rear, facing the drive motor 10, 20, by the rear wall 4. The impeller 15 is rotatably mounted in the pumping chamber about the axis of rotation R. When the rotary drive is engaged, the fluid is drawn in through the inlet 2 towards the end face of the impeller 15, deflected radially outwards as is known from radial pumps, and finally discharged tangentially at the outer circumference of the impeller 15 and expelled through the outlet 3. The rear wall 4 faces axially opposite the rear of the impeller 15 and forms a seal, for example a labyrinth seal, with the impeller 15 to separate the pumping chamber from the motor compartment.

[0054] The conveyor wheel 15 is non-rotatably connected to the drive shaft 16 and, via this shaft, non-rotatably connected to the rotor 10. The rotor 10 and the conveyor wheel 15 are arranged coaxially to each other along the drive shaft 16.

[0055] The motor housing 6 forms a rotary bearing structure 8 for radially supporting the drive shaft 16, in this embodiment for radially supporting the rotary assembly consisting of the rotor 10, impeller 15, and drive shaft 16. The rotary bearing structure 8 comprises a bushing-shaped structural section that surrounds the drive shaft 16 in an axial shaft section to radially support the drive shaft 16 and thus the rotor 10 and the impeller 15. This axial shaft section extends between a front shaft section, in which the drive shaft 16 is rigidly connected to the impeller 15, and a rear shaft section, in which the drive shaft 16 is rigidly connected to the rotor 10. Beyond the rotary bearing structure 8, the bearing arrangement for the drive shaft 16 includes the bearing bushing 17, which projects into the bushing-shaped structural section of the rotary bearing structure 8 and is advantageously rigidly connected to the rotary bearing structure 8.The bearing arrangement also includes the bearing disc 18 (. Fig. 1) which serves for the axial support of the rotor 10, and the seal 19 ( Fig. 1), which extends around the drive shaft 16 and is arranged between a rotor carrier 11 and the bearing disc 18.

[0056] The rotor 10 comprises the rotor carrier 11, which is non-rotatably connected to the drive shaft 16 and projects radially outwards from the drive shaft 16, a magnet holder 12, and several permanent magnets 13, which are arranged on the rotor carrier 11 distributed around the axis of rotation R and held in position by the magnet holder 12. The magnet holder 12 can advantageously be formed as a laminated stack of axially stacked rotor laminations.

[0057] The rotary bearing structure 8 has a radially extending, for example, annular-shaped connecting carrier that rigidly connects the bushing-shaped structural section to the radially outwardly extending section of the motor housing 6. The rotary bearing structure 8 projects with its connecting carrier from the radial outside inwards, towards the drive shaft 16, to the bushing-shaped structural section, and with its bushing-shaped structural section into an annular gap between the drive shaft 16 and the rotor 10. The result is a nested, space-saving arrangement of the drive shaft 16, rotor 10, and rotary bearing structure 8. Furthermore, the drive shaft 16 is advantageously supported radially axially between the non-rotating connection with the rotor 10 and the non-rotating connection with the impeller 15.

[0058] The stator 20 surrounds the rotor 10. The stator 20 has stator teeth 21 with electrical coils 25, a primary insulation 26 between the stator teeth 21 and the coils 25, and a secondary insulation 28. The primary insulation 26 and the secondary insulation 28 enclose the coils 25 in a fluid-tight manner. The coils 25 can be energized via contact lugs 40 and the associated electrical connecting leads 25a. A running gap 14 extends circumferentially around the axis of rotation R between the rotor 10 and the stator 20, bounded radially inwards by the rotor 10 and radially outwards by the stator 20.

[0059] The drive motor 10, 20 is designed as a wet rotor. The fluid conveyed by the impeller 15 is used to cool the drive motor 10, 20. For this purpose, a small partial flow of the fluid is diverted from the conveyed fluid flow in a fluid region of higher pressure, routed through the motor compartment to cool the drive motor 10, 20, and preferably also the end wall 30 and, via this, the circuit board 33 with the electronic components 34, and then returned to a fluid region of lower pressure. The diverted partial flow is driven by a pressure difference that arises between the two fluid regions when the fluid is conveyed. The terms "higher pressure" and "lower pressure" are intended only to indicate that a pressure difference exists between the fluid regions thus characterized, which is sufficient to generate and maintain the partial flow.Advantageously, the partial flow in the conveying housing 1, 4 is diverted from a main flow conveyed by the impeller 15 and / or returned to the main flow in the conveying housing 1, 4. The partial flow can, in particular, be diverted downstream of the impeller 15 and / or returned upstream of the impeller 15.

[0060] In Fig. Figure 3 shows a cooling path along which the partial flow of fluid is routed through the engine compartment. The cooling path extends from a cooling path inlet 4a, located in the higher-pressure fluid region, into the engine compartment and there to the guide gap 14, through the guide gap 14 to the rear of the rotor 10, and from there through the drive shaft 16 to a cooling path outlet 16a, which opens in the lower-pressure fluid region. The cooling path inlet 4a is located upstream of the cooling path outlet 16a in the path of the main flow conveyed by the impeller 15, so that a sufficient pressure differential is established to drive the diverted partial flow. The cooling path inlet 4a passes through a guide gap formed by the impeller 15 and the rear wall 4. Leakage fluid from the outer circumference of the impeller 15 enters the engine compartment through the cooling path inlet 4a.Downstream of the running gap 14, the fluid in the motor compartment comes into contact with the front wall 30 and cools the circuit board 33 via the front wall 30 and the gap filler 32, and via this also the electronic components 34. The cooling path outlet 15a opens at the front of the conveyor wheel 15 towards the inlet 2.

[0061] The cooling path extending through the running gap 14 leads through one or more passages 8a of the rotary bearing structure 8. The respective passage 8a extends upstream of the running gap 14 through the connecting beam of the rotary bearing structure 8.

[0062] The drive shaft 16 is designed as a hollow shaft. The fluid located in the engine compartment between the rotor 10 and the end wall 30 flows into the drive shaft 16 at a rear end and exits into the low-pressure fluid region at a front end. In this embodiment, the drive shaft 16 extends through the impeller 15, and the cooling path outlet 16a is formed at the front end of the drive shaft 16. In a variation, the impeller 15 can form the cooling path outlet.

[0063] The drive motor 10, 20 is not only cooled from the running gap 14. To intensify the cooling, additional fluid from the higher-pressure fluid range is routed through the stator 20. For this purpose, the stator 20 is provided with internal cooling channels 29 that extend axially through the stator 20. After flowing through the stator 20, this portion of the diverted fluid can be combined with the fluid that flowed through the running gap 14 in the motor compartment and also returned to the lower-pressure fluid range via the drive shaft 16 at the cooling path outlet 16a.

[0064] The combination of rotor gap cooling and internal stator cooling provides more intensive cooling with increased and demand-based heat dissipation compared to either of the two measures individually. This is due to a combination of factors. The cooling volume flow can be increased and more precisely adapted to the demand. Furthermore, the surface areas of the stator 20 involved in heat exchange are increased and can also be selected more precisely to meet the requirements. In addition, the ratio of rotor gap flow to cooling channel flow can be used to optimize the cooling performance, allowing for a more precise match to the required cooling capacity.

[0065] In the exemplary embodiment, the cooling channels 29 are connected to the higher-pressure fluid area via one or more passages 4b leading through the rear wall 4. The one or more passages 4b together form a further cooling path inlet. Thus, fluid for cooling reaches the drive motor 10, 20 not only due to unavoidable leakage via the running gap of the conveyor wheel 15.

[0066] The cooling path of the exemplary embodiment comprises two parallel sub-paths that branch off separately from each other in the higher-pressure fluid region and converge in the engine compartment downstream of the running gap 14 and the cooling channels 29 on the one hand, and upstream or at the drive shaft 16 on the other. In variations, the two cooling paths, one through the running gap 14 and the other through the internal cooling channels 29 of the stator 20, can extend separately from the higher-pressure fluid region to the lower-pressure fluid region. In other variations, the cooling path leading through the engine compartment can also branch into the two sub-paths only within the engine compartment. However, the separate additional cooling path inlet allows for finer, yet structurally simple, adjustment to the actual cooling requirements by supplementing unavoidable leakage fluid flowing through cooling path inlet 4a with additional cooling fluid flowing through the further cooling path inlet 4b.

[0067] As especially in the Fig. 4 and Fig. As can be seen in Figure 5, the stator 20 comprises a stator core with several stator teeth 21, which project radially from a ring-shaped stator yoke 22 extending around the axis of rotation R to free tooth ends 23. Electrical conductors are wound around the stator teeth 21 to form the electrical coils 25. The stator teeth 21 serve as pole shoes. The stator core 21, 22, 23 can advantageously be formed as a laminated core of axially stacked stator laminations. The stator laminations can each be arranged in the Fig. have 4 recognizable cross-sections.

[0068] The stator 20 comprises the aforementioned primary insulation 26, which surrounds each of the stator teeth 21 and lines the remaining gaps between the stator teeth 21. The primary insulation 26 is formed between the stator core 21, 22, 23 and the coils 25 and serves to electrically insulate the coils 25. The primary insulation 26 covers the stator core 21, 22, 23 like a skin. Advantageously, it can envelop the stator core 21, 22, 23 to such an extent that only a circumferential or running surface 24 at the tooth ends 23, which defines the running gap 14, remains exposed. Advantageously, the initial insulation 21 is set back slightly behind the running surface 24 at the tooth ends 23, but advantageously completely encloses the stator core 21, 22, 23 apart from this, and thus also at the end faces and on the outer circumference.If the stator core 21, 22, 23 is designed as a laminated core, the primary insulation 26 prevents fluid penetrating between the stator laminations of the laminated core from coming into contact with the coils 25.

[0069] The secondary insulation 28 is formed in the tooth gaps of the stator core 21, 22, 23. This insulation serves to electrically isolate the coils 25 from the fluid flowing through the running gap 14. Together, the primary insulation 26 and the secondary insulation 28 enclose the coils 25 and shield them from contact with the fluid. The secondary insulation 28 therefore also surrounds the coils 25 at both end faces. Furthermore, it also covers the outer circumference of the stator core 21, 22, 23. Advantageously, the secondary insulation 28 completely and fluid-tightly encloses the stator core 21, 22, 23 and the coils 25, with the exception of the running surfaces 24 of the stator teeth 21 that define the running gap 14. Only electrical connecting leads 24a pass through the secondary insulation 28, but these are fluid-tightly enclosed by the secondary insulation 28. The running surfaces 24 at the tooth ends 23 of the stator teeth 21 also remain free of the insulating material of the secondary insulation 28.

[0070] Advantageously, the secondary insulation 21 at the tooth ends 23 is set back slightly behind the circumferential surface 24 of the respective stator tooth 21, but otherwise advantageously completely encloses the stator core 21, 22, 23.

[0071] Since neither the primary insulation 26 nor the secondary insulation 28 covers the running surfaces 24 of the stator teeth 21 that define the running gap 14, and thus the running surface 24 of the respective stator tooth 14 remains free from the insulations 26 and 28, a Fig. The width of the running gap 14, designated by "w", is advantageously small. The running gap width w is the clear distance, measured in the radial direction, between the running surface 24 of the respective stator tooth 21 and the rotor 10. If the running gap width w varies around the circumference because the rotor 10, as in the exemplary embodiment, has radially raised circumferential areas, the running gap width w is measured at the radially narrowest point of the running gap 14.

[0072] In advantageous embodiments, the circumferential surfaces 24 of the stator core 21 are bare. However, they can also be coated with a protective lacquer, which is applied so thinly that the lacquer coating does not cause any significant increase in the running gap w. In any case, any protective lacquer, should one actually be applied, is thinner than the skin-like primary insulation 26.

[0073] The cooling channels 29 extend axially through the secondary insulation 28 in the tooth gaps of the stator core 21, 22, 23. Specifically, one of the cooling channels 29 can extend through the secondary insulation 28 in each tooth gap. The secondary insulation 28 completely surrounds the respective cooling channel 29 and directly forms the channel wall of the respective cooling channel 29. The cooling channels 29 serve to intensify the cooling of the coils 25 from the respective tooth gap towards the adjacent stator teeth 21. The coils 25 and the stator core 21, 22, 23 can thus be intensively and effectively cooled both from the running gap 14 and from the cooling channels 29. If the stator core 21, 22, 23 is designed as a laminated core, fluid from the running gap 14 between the stator laminations can enter the laminated core and penetrate to the first insulation 26, providing an even more effective cooling effect.

[0074] The primary insulation 26 and the secondary insulation 28 together prevent fluid from reaching the coils 25. To shield the coils 25, the primary insulation 26 and the secondary insulation 28 are joined together in contact with each other, at least in the area of ​​the tooth ends 23 around the respective stator tooth 21, creating an impermeable seal against the fluid. In this way, the secondary insulation 28 can, for example, exert a certain pressure on the primary insulation 26 in the direction of the stator core 21, 22, 23, thereby ensuring the necessary seal by means of a frictional connection. Alternatively or additionally, the insulations 26 and 28 can be bonded together by means of adhesives and / or fused near the contact surfaces, or joined using an adhesion promoter. In the area of ​​the tooth ends 23, the insulations 26 and 28 can have continuously circumferential joining geometries around the respective stator tooth 21, which interlock and thereby improve the tightness by means of positive locking.This joining feature can also be combined with a material-bonded and / or force-fit connection. The two insulations 26 and 28 can be joined together everywhere in mutual contact by a material-bonded and / or force-fit connection. In preferred embodiments, however, the first insulation 26 and the second insulation 28 are joined together by a special joining feature at least in a special joining zone that extends annularly around the respective stator tooth 21 between the coils 25 and the running gap 14.

[0075] Fig. Figure 6 shows the stator core 21, 22, 23 with the coils 25 and the first insulation 26, but before the second insulation 28 is produced. Fig. 7 is as a detail from Fig. Figure 6 shows an enlarged view of one of the tooth ends 23. The primary insulation 26 completely envelops the stator core 21, 22, 23 almost entirely, extending to the tooth ends 23. "Almost to the tooth ends" means that the primary insulation 26 extends beyond the coils 25 towards the tooth ends 23, and that sufficient contact area is available between the coils 25 and the tooth ends 23 for a fluid-tight connection with the secondary insulation 28, which is yet to be applied. At least the running surface 24 at each tooth end 23 remains free of the primary insulation 26.

[0076] To ensure the shielding of the coils 25 with increased reliability, the primary insulation 26, in the joining zone already discussed above, which extends annularly around each stator tooth 21 between the coils 25 and the running gap 14, features several annularly arranged joining geometries 27 around each stator tooth 21 as a special joining feature. Each geometrie 27 is in the form of an endless, circumferential, rib-like projection extending from the stator tooth 28. The respective joining geometry 27 projects from the otherwise macroscopically smooth surface of the primary insulation 25 by more than half its thickness.

[0077] In Fig. In section 5, the thickness D of the primary insulation 26 and the height(s) d of the joining geometry(ies) 27 are specified. Advantageously, each joining geometry 27 has a height d, measured on the adjacent smooth surface area, that is greater than 0.2·D or greater than 0.4·D. It is advantageous if the height d is less than 3·D or less than 2·D.

[0078] The primary insulation 26 is formed from an electrically insulating plastic. It is advantageous if the plastic has good thermal conductivity. The plastic can be pure polymer material or, advantageously, filled polymer material. The plastic can be a thermoplastic or thermosetting plastic. The primary insulation 26 can be formed, in particular, by injection molding. For this purpose, the stator core 21, 22, 23 is placed in an injection mold and overmolded with the plastic. After solidification, this plastic forms the primary insulation 26 in the form of an overmold. The joining geometries 27 are expediently formed directly in the mold during injection molding.

[0079] The stator core 21, 22, 23 can be completely encased in the plastic of the primary insulation 26 during injection molding and then exposed again at the circumferential surfaces 24 in an additional process step. Preferably, however, the circumferential surfaces 24 remain free of the plastic of the primary insulation 26 during injection molding. For this purpose, it is helpful if the primary insulation 26 is set back slightly behind the circumferential surfaces 24, i.e., the future running surfaces 24, directly during injection molding, as is best illustrated in the detailed drawings of the Fig. 5 and Fig. 7 is recognizable. This can counteract the formation of so-called webbed feet.

[0080] To manufacture the coils 25, the stator core 21, 22, 23, which is provided with the primary insulation 26 and overmolded in the exemplary embodiment, is wound with electrical conductor material. The coils 25 thus obtained can be energized via electrical coil contacts 25b, which are arranged on the outer circumference of the stator yoke 22 and connected to the coils 25 via the electrical connecting leads 25a. Before the secondary insulation 28 is produced, the coil contacts 25b are connected to contact lugs 40. Fig. In Figure 2, one of the contact tabs 40 is visible. The connection can be made, for example, by resistance welding.

[0081] The wound stator core 21, 22, 23, equipped with the connecting tabs 40, is then overmolded a second time in a further injection mold to produce the secondary insulation 28. This second overmolding is done with the plastic of the secondary insulation 28, so that the coils 25 are completely and reliably shielded against ingress of the fluid located in the engine compartment. After this second overmolding, only the connecting tabs 40 protrude from the secondary insulation 28.

[0082] The secondary insulation 28 is also made of an electrically insulating plastic. It is advantageous if the plastic of the secondary insulation 28 has good thermal conductivity. The plastic of the secondary insulation 28 can be pure polymer material or, advantageously, filled polymer material. The plastic can be a thermoplastic or a thermosetting plastic.

[0083] The Fig. 8 and Fig. Figure 9 shows the stator 20 after overmolding with the plastic of the secondary insulation 28. This is Fig. 8 an isometric projection onto the conveyor wheel 15 ( Fig. 2) facing front and Fig. 9 onto the rear side of the stator 20 facing away from the impeller 15. This second overmolding completely encases the coils 25 and the stator core 21, 22, 23 with the plastic of the secondary insulation 28, creating a fluid-tight seal, so that only the tooth ends 23 or at least their circumferential or running surface 24 remain exposed to the secondary insulation 28. During the second overmolding process, the motor housing 6, the terminal housing 7, and the rotary bearing structure 8 are simultaneously molded in one piece from the same plastic along with the secondary insulation 28.

[0084] The rotary bearing structure 8 with its central bushing-shaped structural area and the ring-shaped connecting carrier, which connects the bushing-shaped structural area with the outer ring area of ​​the motor housing 6 or the secondary insulation 28, are in the Fig. 8 and Fig. 9 clearly visible. It is also clearly visible that the contact tabs 40 on the back of the stator 20 protrude axially from the secondary insulation 28, so that they protrude into the electronics compartment when the pump is assembled.

[0085] The stator 20 also has joining elements 6b that project axially in a pin-like manner from the rear side of the stator 20. The joining elements 6b are also formed directly from the plastic of the secondary insulation 28 during overmolding. They serve to position and fasten the layered structure consisting of end wall 30, gap filler 32, and circuit board 33 ( Fig. 1) relative to and at the stator 20.

[0086] On the side of the stator 20 where the terminal housing 7 is formed, electrical connection elements 42 extend from the rear of the stator 20 or from the electronics compartment of the pump to the outside into the terminal housing 7. Each of the connection elements 42 has an inner contact section 43 and an outer contact section 45. The inner contact sections 43 project freely from the rear of the stator in an axial direction, allowing them to be electrically connected to corresponding electrical terminals on the circuit board 33. The outer contact sections 45 project freely into the terminal housing 7 in an axial direction, allowing them to be connected via corresponding terminals to an external power supply and / or control system, such as the motor control system of a motorized vehicle, particularly a motor vehicle, by establishing a suitable plug connection.

[0087] In the Fig. 10 and Fig. Figure 11 shows in particular the connection elements for the electrical connection of the stator 20 to the external power supply and control system. These are the contact lugs 40 and the connection elements 42 and 46. Fig. Figure 10 shows the wound stator core and the secondary insulation 28, which also forms the motor housing 6, shown separately from each other. This shows Fig. 10 the wound stator core after connecting the contact tabs 40. In this state, the wound stator core is overmolded with the plastic of the secondary insulation 28, while at the same time the motor housing 6 with connection housing 7 and rotary bearing structure 8 is formed.

[0088] Before being overmolded with the secondary insulation material 28, the connection elements 42 and 46 are positioned in the injection mold relative to the wound stator core and are also overmolded with the secondary insulation material 28. After overmolding, they are embedded in the secondary insulation material 28 and fixed in position, with only their inner contact section 43 and outer contact section 45 protruding freely from the plastic. In a side view, the connection elements 42 and 46 are U-shaped, with two side legs, one forming the inner contact section 43 and the other the outer contact section 45, and a central connecting section 44 linking the two side legs.After the formation of the secondary insulation 28 and thus also the motor housing 6, the respective connecting leg 44 extends from the respective inner contact section 43 in a radial direction outwards into the terminal housing 7 and transitions there into the outer contact section 45, which protrudes from the plastic mass in the terminal housing 7.

[0089] In the detailed presentation of the Fig.Figure 12 shows the joining connection by means of which the end wall 30, the gap filler 32, and the circuit board 33 are positioned and attached to the motor housing 6. In the assembled state shown, the joining elements 6b protrude through the layered structure 30, 32, 33, which is provided with corresponding openings for this purpose. The joining elements 6b serve to create a rivet-like joining connection. During assembly, the end wall 30, the gap filler 32, and the circuit board 33 are positioned on the rear of the stator 20 and the motor housing 6, respectively, so that the joining elements 6b protrude through the corresponding openings in the layered structure 30, 32, 33, each with a head section extending beyond the circuit board 33. Subsequently, the head sections are melted or fused so that the joining elements 6b engage behind the circuit board 33 and thereby fix it to the motor housing 6. Reference symbol: 1 Conveyor housing part 1a Joining element, through-hole 2 Entrance 3 Outlets 4 Back panel 4a Cooling path inlet 4b Cooling path inlet 5 Seal 6 Motor housings 6a Joining element, through-hole 6b Joining element 7 Connection housings 8 Rotary bearing structure 8a Passage 9 Fastening element 10 Rotor 11 rotor carriers 12 magnetic holders 13 Permanent magnet 14 Running gap 15 conveyor wheel 16 Drive shaft 16a Cooling path outlet 17 Bearing bushing 18 bearing disc 19 Seal 20 Stator 21 Stator tooth 22 yoke 23 Tooth end 24 inner circumference 25 coil 25a Connection cable 25b Coil contact 26 Initial isolation 27 Joining geometry 28 Secondary insulation 29 Cooling channel 30 Front wall 31 Seal 32 gap fillers 33 circuit boards 34 Engine electronics 35 lids 36 dampers, elastomer ring 37 Assembly structure 38 Mounting flange 40 contact flag 41 Connecting line 42 electrical connection element 43 inner contact section 44 Connecting section 45 outer contact section 46 electrical connection element d Height of the joining geometry The thickness of the initial insulation R axis of rotation w gap width QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2021 133 484 A1

[0003]

Claims

Pump for conveying a fluid, for example a cooling fluid and / or a lubricating fluid, the pump comprising: 1.1 a pump housing (1, 4) with an inlet (2) and an outlet (3) for the fluid, 1.2 a pump impeller (15) rotatable in the pump housing (1, 4) for conveying the fluid from the inlet (2) to the outlet (3), and 1.3 an electric drive motor with a rotor (10) rotatable about a motor axis (R), which is coupled to the pump impeller (15) for its drive, and a stator (20) which forms a running gap (14) with the rotor (10) about the motor axis (R), the stator (20) comprising: 1.4 a stator core (21, 22, 23) with stator teeth (21) pointing at least substantially radially to the motor axis (R) and tooth gaps remaining between the stator teeth (21), 1.5 electrical conductors for forming electrical coils (25) are wrapped around the stator teeth (21),1.6 a primary insulation (26) formed for electrical insulation between the respective stator tooth (21) and the coil (25) surrounding the respective stator tooth (21), 1.7 and a secondary insulation (28) formed for electrical insulation of adjacent coils (25) in the tooth gaps, 1.8 wherein the stator teeth (21) each have a running surface (24) at tooth ends (23) which faces radially opposite the rotor (10) across the running gap (14) and is free from the primary insulation (26) and the secondary insulation (28), 1.9 and in one or more of the tooth gaps a cooling channel (29) through which coolant flows extends in an axial direction through the secondary insulation (28). Pump according to the preceding claim, wherein the first insulation (26) and the second insulation (28) are connected in a manner that is impermeable to the fluid at least in the area of ​​the tooth ends (23) around the respective stator tooth (21), preferably by a material bond, so that the coils (25) are separated from the running gap. Pump according to one of the preceding claims, wherein the first insulation (26) and the second insulation (28) in the region of the tooth end (23) of the respective stator tooth (21) have one or more joining geometries (27) circumferential around the respective stator tooth (21) which interlock to form an annular joining zone impermeable to the fluid in engagement. Pump according to one of the preceding claims, wherein the first insulation (26) and the second insulation (28) form a joining zone extending in a ring shape around the respective stator tooth (21) in the region of the tooth ends (23), in which a microstructure of the first insulation (26) and a microstructure of the second insulation (28) interlock deeper than at the base of the tooth gaps. Pump according to one of the preceding claims, wherein - the first insulation (26) consists of a first plastic and the second insulation (28) consists of a second plastic, - the first insulation (26) and the second insulation (28) are fused in the region of the tooth ends (23) in a joining zone extending in a ring shape around the respective stator tooth (21), and - a mixed structure formed by the first plastic and the second plastic has a greater depth (d) in the ring-shaped joining zone than at the base of the tooth gaps. Pump according to one of the preceding claims, wherein the first insulation (26) completely encloses the stator core (21, 22, 23) up to the tooth ends (23), so that only the tooth ends (23) are free from the first insulation (26) at least on their running surface (24) which limits the running gap (14). Pump according to one of the preceding claims, wherein the respective cooling channel (29) is an axially extending passage, preferably a straight, axial passage, through the secondary insulation (28). Pump according to one of the preceding claims, wherein a cooling path for the fluid extends from a cooling path inlet (4a, 4b) which opens into the pump housing (1, 4) in a region of higher pressure, through the flow gap (14) and / or the respective cooling channel (29) to a cooling path outlet (16a) which opens into the pump housing (1, 4) in a region of lower pressure. Pump according to one of the preceding claims, wherein the rotor (10) of the drive motor and the impeller (15) are arranged coaxially along a drive shaft (16) rotatable about the axis of rotation (R), which is preferably formed as a hollow shaft. Pump according to one of the preceding claims, wherein the secondary insulation (28) completely encloses the stator core (21, 22, 23) and the coils (25) up to the tooth ends (23), so that only the tooth ends (23) of the stator core (21, 22, 23) are free from the secondary insulation (28) at least on their running surface (24) which limits the running gap (14). Pump according to one of the preceding claims, wherein the secondary insulation (28) is formed in one piece, for example as a casting made of plastic, together with a motor housing (6) surrounding the stator core (21, 22, 23) and / or together with a connection housing (7) for the electrical connection to an external system for the power supply and / or control of the drive motor (10, 20) and / or together with a rotary bearing structure (8) for radially supporting a drive shaft (16) non-rotatably connected to the rotor (10) and / or the impeller (15). Pump according to one of the preceding claims, wherein the secondary insulation (28) forms a connection housing (7) for one or more electrical connection elements (42, 46) and the stator (20) can be connected to an external power supply and / or control system via the connection housing (7) and the respective connection element (42, 46), for example by means of a plug connector connection. Pump according to one of the two immediately preceding claims, wherein the respective electrical connection element (42, 46) is embedded in the secondary insulation (28) and is thereby positioned and fixed relative to the connection housing (7) and / or relative to the motor housing (6). Pump according to one of the preceding claims, comprising a rotary bearing structure (8) for rotary bearing of the rotor (10), wherein the secondary insulation (28) and the rotary bearing structure (8) are formed in one piece by primary forming, for example as an injection molded part made of plastic. Pump according to one of the preceding claims, wherein the running gap (14) has a radial running gap width w, which is measured radially to the axis of rotation (R) between the running surface (24) of one of the stator teeth (23) and a circumference of the rotor (10) opposite the running gap (14), and the first insulation (26) in the region of the tooth ends (23) has a thickness D, wherein w < D or w < 0.5•D. Pump according to one of the preceding claims, wherein the first insulation (26) and the second insulation (28) are radially recessed behind the running surfaces (24) of the stator teeth (23) in the area of ​​the tooth gaps or instead, the first insulation (26) and the second insulation (28) are flush with the running surfaces (24) of the stator teeth (23) in the area of ​​the tooth gaps. Pump according to one of the preceding claims, which is designed as a cooling media pump for conveying a water / glycol mixture and / or a dielectric heat transfer oil for cooling or temperature control (cooling and / or heating) of an internal combustion engine and / or of powertrain components of an internal combustion engine vehicle powertrain and / or of components of the powertrain of a battery electric vehicle and / or of the battery cells of a traction battery of a motor vehicle. Method for manufacturing a stator for an electric drive motor, preferably the stator (20) for the drive motor of the pump according to one of the preceding claims, comprising the following steps: 18.1 A stator core (21, 22, 23) having stator teeth (21) pointing at least substantially radially to a motor axis (R) with free tooth ends (23) and tooth gaps remaining between the stator teeth (21), is overmolded with an electrically insulating first plastic to form a primary insulation (26) which surrounds the stator teeth (21) and preferably lines the tooth gaps, 18.2 Electrical conductors are wound around the stator teeth (21) provided with the primary insulation (26) to form electrical coils (25), 18.3 The stator core (21, 22, 23) and the coils (25) are overmolded with an electrically insulating second plastic to form a secondary insulation (28) which encloses the coils (25) and the stator core (21, 22, 23) beyond the coils (25) to the tooth ends (23), and 18.4 during the injection molding of the secondary insulation (28), cooling channels (29) extending axially through the secondary insulation (28) are formed in the area of ​​the tooth gaps for the passage of a fluid serving to cool the stator, 18.5 wherein a running surface (24) at the tooth ends (23) is free from the primary insulation (26) and the secondary insulation (28) to form a running gap (14) with a rotor (10) of the drive motor. Method according to the preceding claim, wherein the first insulation (26) and the second insulation (28) are injected such that the running surface (24) remains free of the first plastic and free of the second plastic during injection molding. Method according to one of the two immediately preceding claims, wherein the first insulation (26) in the region of the tooth ends (23) is injection molded with one or more joining geometries (27) circumferential around the respective stator tooth (21) in the form of one or more projections and / or recesses (27), and the respective joining geometry (27) is melted or fused to the second plastic during injection molding of the second insulation (28), so that the respective joining geometry (27) engages in the second insulation (28) in the case of fusion or forms a microscopically mixed structure with the first plastic in the case of fusion.

Images