Pump comprising an electric drive motor and a stator cooling system

Abstract

A pump for conveying a fluid, comprising a conveying housing (1, 4) having an inlet (2) and an outlet (3) for the fluid, an impeller (15) rotatable within the conveying housing (1, 4) for conveying the fluid, and an electric drive motor (10, 20) comprising a rotor (10) and a stator (20), the rotor being connected to the impeller for driving the impeller, the stator and the rotor jointly forming a running gap (14) around a motor axis (R). The stator comprises a stator core (21, 22, 23) having stator teeth (21) and tooth gaps remaining between the stator teeth, electric wires wound on the stator teeth (21) to form electric coils (25), a primary insulation layer (26) formed between a respective stator tooth (21) and the coil (25) surrounding the stator tooth (21) for electrically insulating the same, and a secondary insulation layer (28) formed in the tooth gaps for electrically insulating adjacent coils (25).

Description

Technical Field

[0001] This invention relates to a pump driven by an electric drive motor to deliver fluid, preferably a liquid. For example, the delivered fluid may be a cooling fluid and / or a lubricating fluid for cooling and / or lubricating one or more components of a motor vehicle's traction drive system. The pump may particularly be a cooling pump and / or lubrication pump for motor vehicles, such as for cooling and / or lubricating the main battery of a pure electric drive vehicle or a hybrid vehicle and / or cooling and / or lubricating the electric traction motor, or for cooling and / or lubricating the internal combustion engine of a hybrid vehicle or a pure internal combustion engine drive vehicle. Background Technology

[0002] To deliver coolant in motor vehicles, electrically driven pumps, primarily designed as centrifugal pumps, are increasingly being used. The electric drive motors used for this purpose are currently mainly electronically commutated, i.e., brushless DC motors (BLDC motors), typically operating at 12, 25, or 48 volts. These integrated or pump-embedded motors can be designed as so-called wet or dry runners. In dry-running pumps, the motor is typically supported by rolling bearings, while the fluid-contacting parts of the pump are sealed relative to the motor by shaft seals, such as shaft seal rings (lip seals). Due to the significant cost of large, expensive rolling bearings, technically complex shaft seals, relatively complex motor cooling schemes, and control circuit boards integrated into the pump's motor housing, dry-running pumps are not widely used in passenger car coolant pumps. In wet pumps, at least some components of the motor, such as the rotor and rotor bearings, are wetted by the delivered medium.

[0003] DE102021133484A1 discloses a fluid pump integrating an electric drive motor through which a fluid to be pumped is passed for cooling. The drive motor includes a stator with a stator core wound with wires to form an electrical coil. Before winding, the stator core undergoes primary insulation treatment; after winding and connecting, it undergoes secondary insulation injection molding to form an injection-molded layer of insulating sleeve. On the outer and / or inner circumference of the stator, the surrounding cooling structure has axially parallel, slotted cooling channels and grooves formed circumferentially between the cooling channels. These grooves correspond to the cooling channels in such a way that the stator laminations exposed within the grooves can be surrounded and flushed by the fluid. Summary of the Invention

[0004] The objective of this invention is to realize a compact and low-cost pump equipped with an electric drive motor, which has high overall efficiency and effective cooling function.

[0005] The pump is preferably suitable for use in motor vehicles and is used to deliver cooling and / or lubricating fluids.

[0006] An ideal electric drive motor for a pump should be compact, highly efficient, and effectively cooled by the fluid.

[0007] The objective of this invention can also be viewed as creating a compact, efficient, and inexpensive electric pump.

[0008] The subject of this invention is a pump for conveying fluids, such as cooling and / or lubricating fluids. The fluid may be a gas, particularly a liquid. The pump includes a delivery housing with a fluid inlet and outlet, an impeller rotating within the delivery housing about a rotation axis to convey the fluid, and an electric motor for driving the impeller. The drive motor includes a stator and a rotor rotatable relative to the stator and the delivery housing about a motor axis, the rotor being connected to the impeller to drive the impeller to rotate. The stator surrounds the rotor and, together with the rotor, forms an operating clearance extending around the motor shaft. The stator has a stator core with stator teeth extending at least substantially radially toward the motor shaft, and electrical coils wound on the stator teeth. To electrically isolate the coils from the stator core, the stator includes a primary insulation layer surrounding the circumference of each stator tooth and formed between the respective stator tooth and the coil surrounding that stator tooth. Another component of the stator is a secondary insulation layer formed in the gaps between adjacent stator teeth for electrically isolating adjacent coils.

[0009] The stator core is preferably a lamination assembly composed of axially stacked stator laminations. This lamination structure design allows for easy adjustment of the axial length of the stator core by changing the number of stacked stator laminations, thus enabling the torque generated by the drive motor to be adjusted according to application requirements. Therefore, the drive motor can be easily and flexibly adjusted to meet the torque demands of the application scenario without altering its basic structure.

[0010] According to a first aspect of the invention, the stator teeth have neither a primary nor a secondary insulating layer at their tips, and these tips are directly opposite the rotor radially via an operating gap. The stator teeth may be covered with a thin layer of varnish at their radially opposite tips. Preferably, at least the radial circumferential surface facing the rotor is uncoated in the tip region. By ensuring that the tips of the stator teeth are not covered by either the primary or secondary insulating material on their radially facing circumferential surface (hereinafter also referred to as the sliding surface), an operating gap with a smaller radial operating gap width can be achieved. The smaller the radial operating gap width, the lower the flux density loss through the operating gap, thus allowing for a reduction in coil size and a corresponding reduction in the amount of material used in the coil windings while maintaining the same coil power. Therefore, a high-performance, high-efficiency, compact, and low-cost, competitive drive motor can be achieved.

[0011] Because the stator teeth are not covered with insulating material from the primary and secondary insulation layers on their radial circumferential sliding surfaces facing the rotor (which define the operating gap), they are directly subjected to the scouring effect of cooling fluid when it flows through the operating gap. The cooling effect is further enhanced when the metal on the radial sliding surfaces of each stator tooth facing the rotor is exposed. If the stator core is designed as a laminated assembly, coolant can enter between the stator laminations from the operating gap, thus advantageously cooling the stator core from the inside.

[0012] In an advantageous embodiment, the operating clearance between the rotor and stator, measured radially towards the axis of rotation, has a radial operating clearance width that is less than the average thickness of the primary insulation. If the primary insulation layer preferably covers the stator core in a skin-like manner, then in such embodiments, the radial operating clearance width is less than the thickness of this "skin." The advantage is that the operating clearance can have a radial operating clearance width that only accommodates component and positional tolerances and the bearing clearance of the drive motor, preventing contact between the sliding surfaces of the stator teeth and the relative sliding surfaces of the rotor during pump operation.

[0013] To effectively cool the drive motor under high power density conditions achieved by reducing the operating clearance width, according to a second aspect of the invention, one or more tooth gaps are each provided with a cooling channel through which cooling fluid can flow, the cooling channel extending axially through the secondary insulation layer. Where appropriate, each tooth gap is provided with a cooling channel through which coolant can pass, extending axially through the secondary insulation layer. In one or more tooth gaps, two or more cooling channels, each through which cooling fluid can flow, extend axially through the secondary insulation layer. However, it is preferable that only such a cooling channel extends in each tooth gap. Preferably, the secondary insulation layer surrounds each cooling channel uninterruptedly along its entire axial length. In a variation, the corresponding cooling channel may also be at least partially open toward the motor axis, i.e., radially inward. The circumferential wall of each cooling channel may be formed by a tubular insert embedded in the secondary insulation layer. However, it is preferred that the secondary insulation layer (i.e., the material constituting the insulation layer) directly forms the channel wall. The corresponding cooling channel may in particular be formed as a straight axial through-hole, and / or an axially opposite end face leading to the secondary insulation layer.

[0014] Advantageously, the cross-sectional area of ​​each cooling channel at any point along its entire length is at least half the cross-sectional area of ​​the corresponding tooth gap measured between adjacent coils. The closer the cooling fluid is to the stator core and / or coils as it flows through the respective cooling channels, the better the heat dissipation from the stator core and / or coils.

[0015] During pump operation, the stator is cooled through the operating gap and internal cooling channels. Combining operating gap cooling and cooling channel cooling enables denser and more efficient cooling of the stator and rotor (the rotor directly benefits from cooling through the operating gap) and indirectly benefits from cooling channel cooling through the stator. Compared to using either measure alone, the coolant can flow through the drive motor at a higher flow rate. A larger overall heat exchange area is available for convection, providing more room for optimization. Furthermore, the coils are cooled internally through the stator teeth and preferably thermally conductive primary insulation layer, and externally through the tooth gap and preferably thermally conductive secondary insulation layer. It should be noted that, in a preferred embodiment, the pump is designed such that cooling fluid can flow simultaneously through the operating gap and cooling channels during pump operation. In particular, the fluid transported by the impeller can be used as the cooling fluid.

[0016] The primary insulation layer shields the coil, preventing it from contacting the stator core, and, when the stator core is designed as a laminated structure, prevents coolant from seeping between the stator laminations. The secondary insulation layer shields the coil on the outer side of the stator end face and, together with the primary insulation layer, blocks cooling fluid flowing through the operating gap in the preferred embodiment. Preferably, the primary and secondary insulation layers together enclose the coil and shield it to prevent coolant ingress. The corresponding insulating material should be an electrical insulator, but preferably a good thermal conductor.

[0017] The primary and secondary insulating layers form a fluid-sealed connection, at least in the tooth-end region, around each stator tooth, with an endless circulation, meaning it is impermeable to fluid. This fluid-sealed connection can be achieved, in particular, based on material bonding. Therefore, the primary and secondary insulating layers, at least in the tooth-end region, can be connected along the annular engagement area of ​​their respective stator teeth using a fluid-impermeable material bonding method, such as by adhesive bonding or preferably fusion. If a special engagement area exists in the stator tooth-end region, this engagement area forming around each stator tooth extends between the sliding surface and the stator tooth coil.

[0018] To ensure a tight seal and improve safety, the primary and secondary insulating layers may have one or more engagement geometries extending infinitely circumferentially along each stator tooth in the tooth tip region. These structures interlock and, upon engagement, form an annular, fluid-tight engagement area. The corresponding engagement geometry may be a protrusion or recess surrounding each stator tooth. Preferably, one or more grooves extend continuously circumferentially in each tooth tip region of the stator tooth. The corresponding protrusion may be annular disc-shaped with rounded edges, or preferably sharp corners or angular edges. The primary and secondary insulating layers may form an annular engagement area surrounding each stator tooth in the tooth tip region, where the microstructures of the primary and secondary insulating layers interlock to a depth greater than the bottom of the tooth gap. The engagement depth is measured on the circumference of the stator tooth, perpendicular to the circumferential surface of the stator tooth in contact with the primary insulating layer. In an advantageous embodiment, the primary insulating layer wraps around the corresponding stator tooth as a skin. Therefore, the engagement depth is measured perpendicular to this "skin".

[0019] One or more bonding geometries of the primary insulation layer and one or more bonding geometries of the secondary insulation layer can be interlocked by form fit and / or friction fit, forming the desired seal in the form fit and / or friction fit. Preferably, they are connected in a material bonding manner in the annular connection area, such as by adhesive bonding, or more advantageously by fusion. If they are only surface fused, interlocking still exists between the bonding geometries after fusion, although the bonding geometries may be deformed due to the melting process compared to their shape before fusion. The bonding geometries can in particular be interlocked in a comb-like manner. This connection can correspond geometrically to a labyrinth seal, but the difference is that there is no relative movement between the interlocking connecting geometries. When the bonding geometries are completely melted, the annular connection area may appear prominent due to the molten structure formed during the melting process. If the primary and secondary insulation layers are made of the same material and their respective bonding geometries are completely melted, the joint area formed at each tooth tip may only have the following characteristics: no transition traces are visible in the joint area between the primary and secondary insulation layers. However, in such implementations, transition areas may still be observed in addition to the annular connection area (radially further away from the operating gap) and / or the bottom of the tooth gap. In principle, the primary and secondary insulation layers may also be partially or entirely fused together outside the joint area specific to the tooth region, without a noticeable transition.

[0020] Advantageously, the bonding geometry of the primary insulation layer has one or more edges at its free outer peripheral edge before the fabrication of the secondary insulation layer, such as extending in a pointed shape or having a flat cylindrical outer peripheral edge with two edges. Such a peripheral edge is particularly conducive to fusion, especially when the primary insulation layer is shaped such that its respective bonding geometry can be fused along one or more edges during the forming of the secondary insulation layer.

[0021] To improve the sealing between the primary and secondary insulation layers, alternative or supplementary solutions exist besides the comb-like interlaced structure. Therefore, the primary insulation layer can undergo plasma / corona activation and / or laser structuring treatment in the bonding area or the entire contact surface before the formation of the secondary insulation layer. Alternatively, chemical activation can be performed in the bonding area or the entire contact surface. After the primary and secondary insulation layers are injection molded, these two contacting insulation layers can still undergo post-sealing treatment, such as using a liquid sealant, which is drawn into or forced into the sealing gap between the two insulation layers by creating a pressure differential, as is common in casting vacuum sealing processes.

[0022] In an advantageous embodiment, the primary insulating layer is made of an electrically insulating first plastic, and the secondary insulating layer is made of an electrically insulating second plastic, and they are fused together in a mating region extending circumferentially along each stator tooth in the tooth tip region, as described above. The first and second plastics can be fused or form a hybrid structure in the annular connection region. If the primary and secondary insulating layers are also fused together outside the annular connection region, for example at the bottom of the tooth gap, then the depth of the hybrid structure within the annular connection region will be greater than the depth of the fused or hybrid structure at the bottom of the tooth gap. A greater depth can be achieved by giving the primary insulating layer one or more mating geometries in the subsequent annular connection region before the secondary insulating layer is manufactured, such as one or more bosses and / or one or more grooves around each stator tooth. Preferably, the primary insulating layer is formed by one or more bosses formed around the corresponding stator tooth.

[0023] If the secondary insulation layer is preferably manufactured by injection molding, the primary insulation layer can be partially or completely melted, particularly in the areas of the bonding geometry, during the overmolding process, thereby forming a particularly tight material bond between the first and second plastics within the annular bonding area. At the beginning of the overmolding process, the bonding geometries exposed to the secondary insulation layer melt have a larger thermally conductive surface area relative to their mass. Therefore, compared to the smooth surface of the primary insulation layer, the bonding geometries rapidly and partially melt and / or completely melt, forming a fluid-sealed connection between the primary and secondary insulation layers upon cooling.

[0024] The first and second plastics can be identical in material; therefore, the designations "first plastic" and "second plastic" refer only to their point in time of production. In alternative embodiments, the first and second plastics can differ in terms of polymer materials. If the first and / or second plastics have a polymer matrix and one or more fillers in the polymer matrix, then the first and second plastics can differ in terms of polymer matrix material and / or one or more fillers. If the two plastics differ in polymer composition and / or fillers, and the bonding geometry of each bonding region is fully fused, then the concentration gradient of the melt structure of the bonding region relative to the polymer composition and / or the filler is smaller than the concentration gradient at the bottom of the gap.

[0025] Thermoplastic and thermosetting plastics can be considered as materials. The insulation layer can be either thermoplastic or thermosetting. In principle, a combination of thermosetting primary insulation layer and thermoplastic secondary insulation layer can also be used, or a combination of thermoplastic primary insulation layer and thermosetting secondary insulation layer can be adopted.

[0026] In a preferred embodiment, the primary and secondary insulation layers jointly enclose the coil, providing electrical isolation between them and from the stator core, thereby isolating the motor compartment from fluid. The primary insulation layer can enclose the stator teeth along the tooth tip direction and extend beyond the coil, completely covering the stator core up to the tooth tip area. For example, a skin-like covering method can be used, ensuring that only the tooth tips (at least on the mating surfaces defining their operating clearances) remain free of the primary insulation layer. The secondary insulation layer can enclose both the stator core and the coil, ensuring that only the tooth tips, at least on their sliding surfaces, are not covered by the secondary insulation layer, while connecting elements for electrical connections to the coil can pass through the secondary insulation layer.

[0027] In the first variation, the primary insulation layer covers the stator core up to the sliding surface immediately adjacent to the stator teeth, while the secondary insulation layer fills the tooth gaps up to the sliding surface immediately adjacent to the stator teeth, so that the sliding surface of the stator teeth is flush with the insulating material located in the tooth gaps. Therefore, the turbulence intensity of the coolant within the operating gaps can be reduced. In the second variation, the insulating material located in the tooth gaps is slightly recessed radially behind the sliding surface, thus exposing the sliding surface radially. In the first variation, the sliding surface of the stator core and the insulating material located in the tooth gaps preferably together form a smooth cylindrical stator sliding surface. In the second variation, the exposed sliding surface of the stator core preferably together form a cylindrical stator sliding surface protruding above the tooth gaps towards the rotor direction.

[0028] The rotor and impeller of the drive motor can be coaxially mounted and rotate about a common axis of rotation. The rotor and drive motor are connected via a drive shaft for transmitting torque. They are preferably rotatably fixed to the drive shaft. The drive shaft is preferably designed as a hollow shaft.

[0029] To cool the drive motor, the cooling path of the cooling fluid extends from the cooling path inlet to and through the operating gap and / or to and through the corresponding cooling channel of the stator, and continues to the cooling path outlet. The cooling path inlet and outlet can be connected to the main flow fluid driven by the impeller, so that fluid is diverted from the main flow for cooling the drive motor, and the fluid flows through the motor nacelle and then rejoins the main flow. Preferably, the cooling path inlet is located in a higher pressure region of the main flow channel, while the cooling path outlet is located in a lower pressure region, such that during pump operation, a pressure difference exists between the cooling path inlet and outlet, which alone is sufficient as a driving force to propel the fluid through the cooling path of the motor nacelle.

[0030] The cooling path inlet and / or cooling path outlet may each open within the delivery housing to divert and / or return the fluid used for cooling the pump's internal drive motor to the main flow. Thus, the cooling path inlet may open into a higher-pressure fluid region within the delivery housing, and / or the cooling path outlet may open into a lower-pressure fluid region within the delivery housing. The cooling path inlet may specifically open into the delivery chamber, for example, in the outlet region downstream of the impeller or between the impeller and the outlet. The cooling path outlet may preferably open in the inlet region upstream of the impeller, particularly at the impeller front side facing the inlet.

[0031] The cooling path can be divided into two branches between the high-pressure and low-pressure regions: the first path passes through the operating gap, and the second path passes through the corresponding cooling channel of the stator. It can also split into two paths downstream of the cooling path inlet. Preferably, it further branches in the higher-pressure region by providing a first cooling path inlet and a separate second cooling path inlet there, allowing fluid to flow through the first cooling path inlet to the operating gap and through the second cooling path inlet to the stator's cooling channel.

[0032] The two cooling paths can converge in the low-pressure region. Preferably, they still converge within the nacelle, during operation, and downstream of the cooling channel, allowing fluid to exit the nacelle through a shared cooling path outlet and preferentially return to the main flow. If the drive shaft is hollow, the fluid can preferably return through this drive shaft. In this case, the drive shaft or impeller can constitute the cooling path outlet.

[0033] In an advantageous embodiment, the secondary insulation layer wraps around the winding stator core along its outer circumference. It can preferably extend into an engine housing, going beyond the outer casing function. This delivery housing can be directly connected to this motor housing, for example, via a threaded connection.

[0034] The secondary insulation layer can form a wiring housing for one or more electrical connection elements, through which a motor can be connected to an external system for power supply and / or control. The wiring housing can be configured for mating connections with corresponding molded connectors. Each connection element can be embedded in the secondary insulation layer, thereby being positioned and fixed relative to the motor housing and the wiring housing. Therefore, the corresponding electrical connection elements can include inner connection contacts, outer connection contacts, and connecting segments connecting the inner and outer connection contacts. The connecting segments can be embedded in the secondary insulation layer. The inner connection contacts can extend from the secondary insulation layer for connecting electrical interfaces of the motor electronics. The outer connection contacts can extend from the secondary insulation layer to achieve electrical connection with an external system within the wiring housing.

[0035] The secondary insulation layer may include an assembly geometry for mounting the pump in the desired location. The assembly geometry can be formed directly during the initial molding of the secondary insulation layer. It may have one or more mounting elements, such as one or more protruding mounting flanges. This assembly geometry is particularly designed for assembling the pump via threaded connections. For example, the mounting geometry may form one or more exposed channels for one or more fastening elements (such as screws). The assembly geometry may include one or more resilient connecting elements that connect to the secondary insulation layer via form-fit and / or friction fit, and directly contact the corresponding fastening elements in the pump's assembled state. In the pump's mounted state, the individual resilient connecting elements act as shock absorbers between the pump mounting assembly (e.g., drive motor, gearbox, or vehicle body) and the pump.

[0036] The secondary insulation layer may preferably extend beyond the housing function to form a rotary bearing structure for rotor rotation support, wherein the secondary insulation layer and the rotary bearing structure are preferably integrally formed by a one-piece molding process, for example, as a plastic casting. The rotary bearing structure may have one or more channels. The cooling paths described above may extend upstream or downstream of the operating clearance through corresponding through-holes in the rotary bearing structure.

[0037] An electromechanical device, comprising a circuit board and electronic components arranged thereon for powering and controlling a motor, can be integrated as a component of a pump. A secondary insulating layer may be configured with connecting elements that engage with the circuit board to secure it relative to a stator. For example, these connecting elements may be pin-shaped, extending from the stator towards the back of the impeller and through the circuit board. The connecting elements may also form connecting rivets, allowing the circuit board to be connected to the stator by riveting (e.g., thermal riveting).

[0038] Preferably, the secondary insulation layer is integrally formed by a one-piece molding process, for example, as a plastic casting. Regarding the aforementioned additional functionality, this means that the secondary insulation layer can preferably be co-formed in a one-piece molding process with the motor housing surrounding the stator core and / or with a wiring housing for connecting to external systems for powering and / or controlling the drive motor, and / or with a rotary bearing structure for radially supporting a drive shaft that is fixedly connected to the rotor and / or impeller for rotation.

[0039] The additional functions of the secondary insulation layer can be implemented individually, or more advantageously, in any combination. Each additional function can be implemented without feature 1.8, i.e., the primary and / or secondary insulation layers can also cover the sliding surface of the stator. Similarly, each additional function can be implemented without feature 1.9, i.e., the stator does not have the cooling channels according to the invention, or does not have channels for fluid at all. On the other hand, each additional function can be implemented using feature 1.8 of claim 1 or alternatively using feature 1.9, i.e., it can be implemented individually, or preferably together with features 1.8 and 1.9 of claim 1.

[0040] For example, the pump can be designed as a centrifugal pump, particularly a radial centrifugal pump, with a radial impeller. The drive motor can be designed as an outer rotor, with the rotor surrounding the stator, so that the sliding surface of the stator is an outer circumferential surface. However, the drive motor is preferably an inner rotor, with the stator surrounding the rotor, so that the sliding surface of the stator is an inner circumferential surface. The rotor is preferably equipped with permanent magnets, but coils can also be used alternatively. In principle, this configuration can also be reversed, i.e., only the rotor is equipped with coils, while the stator is equipped with permanent magnets. In such embodiments, permanent magnets replace the coils of the stator. Additional cooling achieved through stator cooling channels, in addition to intermittent cooling, is also advantageous for such improved designs. For example, cooling channels can extend axially through the stator between the permanent magnets.

[0041] The pump is particularly suitable as a cooling medium pump for conveying water / glycol mixtures and / or dielectric heat transfer oils to cool or regulate the temperature of one or more components of a motor vehicle (such as an automobile). More specifically, it can be used for temperature regulation of the following objects: Internal combustion engine and / or Transmission components and / or drivetrain of fuel-powered vehicles Components and / or parts of the battery-powered electric vehicle drive system Battery cells of motor vehicle traction batteries "Temperature regulation" means that the pump is used for cooling only, heating only, or both as needed. Specifically, it can be used as a cooling medium pump to deliver dielectric heat-conducting oil for temperature regulation via direct heat exchange, i.e., for directly cooling and / or directly heating the battery cells of a motor vehicle's traction battery.

[0042] In a preferred embodiment, the pump is designed for variable speed control via a vehicle control unit or an engine control unit, and can be driven by the vehicle control unit or engine control unit based on one or more measured parameters, such as external temperature and / or the temperature of the vehicle component to be regulated.

[0043] The present invention also relates to a method for manufacturing a stator for an electric drive motor, preferably a stator for a drive motor of the pump disclosed herein. The method includes at least the following steps: - A stator core, wherein stator teeth extending at least substantially radially along the motor axis have free tooth ends and a tooth gap maintained between the stator teeth, forms a primary insulating layer by injection molding an electrically insulating first plastic, which surrounds the stator teeth and preferably lining the tooth gap. This can also be referred to as the first injection molding.

[0044] - Wires are wound around the stator teeth with a primary insulation layer to form an electrical coil.

[0045] The stator core and coils are injection molded with an electrically insulating second plastic to form a secondary insulation layer. This insulation layer extends from the coil area to the tooth tip, covering the coils and stator core. This can also be called secondary injection molding.

[0046] - During the spraying of the secondary insulation layer, a cooling channel is formed axially through the insulation layer in the tooth gap area to guide the fluid cooling the stator through.

[0047] The stator has circumferential or sliding surfaces at the tooth tips to form an operating clearance with the rotor of the drive motor. These sliding surfaces lack primary and secondary insulation layers. Therefore, the sliding surfaces can be pre-molded with primary insulating plastic during the initial injection and / or with secondary insulating plastic during the second injection, with the corresponding plastic removed from the sliding surfaces in subsequent processing steps. However, it is advantageous that both the first and second injections are performed in such a manner that neither the first nor the second injection covers the sliding surfaces with plastic.

[0048] Preferably, a primary insulating layer is injection molded in the tooth tip region by one or more engagement geometries (in the form of one or more bosses and / or grooves) arranged circumferentially around each stator tooth. During the spraying of the secondary insulating layer, the engagement geometries in contact with the second plastic are heated to soften or melt. Thus, in the case of softening only, the engagement geometry will embed into the secondary insulating layer after cooling; while in the case of melting, it will form a hybrid structure with the first plastic at the microscopic level.

[0049] Features of the invention are also described in the aspects set forth below. These aspects are set forth in the form of claims and may replace these claims. The features disclosed in each aspect may further supplement and / or limit the claims, show alternatives to individual features, and / or extend the features of the claims. Reference numbers in parentheses refer to embodiments of the invention described in the following figures. They do not limit the literal meaning of the features in the aspects, but rather show preferred ways of implementing the various features.

[0050] 1. A pump for conveying fluids, such as cooling fluids and / or lubricating fluids, said pump comprising: 1.1 A delivery housing (1, 4) having an inlet (2) and an outlet (3) for the fluid. 1.2 An impeller (15) rotatable within the conveying housing (1, 4) for conveying the fluid from the inlet (2) to the outlet (3); and 1.3 An electric drive motor (10, 20) comprising a rotor (10) and a stator (20), the rotor (10) being rotatable about a motor axis (R) and connected to the impeller (15) to drive the impeller, the stator (20) and the rotor (10) together forming an operating clearance (14) around the motor axis (R), the stator (20) comprising: 1.4 Stator core (21, 22, 23) having stator teeth (21) and tooth gaps, the stator teeth (21) pointing at least substantially radially toward the motor axis (R), and the tooth gaps remaining between the stator teeth (21); 1.5 Wire, which is wound around the stator teeth (21) to form an electrical coil (25); 1.6 A primary insulating layer (26), formed between a corresponding stator tooth (21) and a coil (25) surrounding the stator tooth (21), for electrically insulating it; and 1.7 Secondary insulating layer (28), which is formed in the tooth gap for electrical insulation of adjacent coils (25); 1.8 Wherein, each of the stator teeth (21) includes a sliding surface (24) at the tooth tip (23), the sliding surface facing the rotor (10) radially and being disposed opposite to the rotor through the running gap (14), and the sliding surface does not cover the primary insulation layer (26) and / or the secondary insulation layer (28). 1.9 and / or in each of one or more of the said tooth gaps, a cooling channel (29) through which coolant can flow extends axially through the secondary insulation layer (28).

[0051] 2. The pump according to the preceding aspect, wherein the primary insulation layer (26) and the secondary insulation layer (28) are connected in a fluid-impermeable manner around each of the stator teeth (21) at least in the tooth end (23) region, preferably by means of material bonding, thereby isolating the coil (25) from the operating gap (14).

[0052] 3. The pump according to the preceding aspect, wherein the primary insulation layer (26) and the secondary insulation layer (28) are fluid-sealed in at least the tooth end (23) region, within the annular engagement area surrounding each stator tooth (21) by a material bonding method, preferably by fusion bonding.

[0053] 4. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) surrounds the stator teeth (22) in the coil (25) region, preferably lining the tooth gaps near the tooth ends (23), and at least in the tooth end (23) region, forms a fluid-tight connection with the secondary insulation layer (28) by material bonding (e.g., fusion) in the annular engagement area surrounding each stator tooth (21).

[0054] 5. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) and the secondary insulation layer (28) have one or more engagement geometries (27; 27a) extending around the respective stator teeth (21) in the tooth tip (23) region of the respective stator teeth (21), the geometries interlocking to form an annular engagement zone for fluid sealing upon engagement.

[0055] 6. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) and the secondary insulation layer (27) are provided with one or more bosses (27; 27a) surrounding the stator tooth (21) and one or more corresponding grooves in the tooth end (23) region of the respective stator tooth (21), the structures engaging with each other to form an annular engagement area for fluid sealing.

[0056] 7. The pump according to any of the foregoing aspects, wherein the primary insulating layer (26) and the secondary insulating layer (28) form an annular joint area around the stator tooth at the tooth tip (23) region of their respective stator teeth (21), the annular joint area being fused to each other by an enlarged surface contact compared to the joint area located at the bottom of their respective tooth gaps.

[0057] 8. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) and the secondary insulation layer (28) form an engagement region extending annularly around each stator tooth (21) in the tooth tip (23) region, wherein the microstructure of the primary insulation layer (26) and the microstructure of the secondary insulation layer (28) are interlocked to a depth greater than the bottom of the tooth gap.

[0058] 9. The pump according to any of the foregoing aspects, wherein - The primary insulation layer (26) is made of a first plastic, and the secondary insulation layer (28) is made of a second plastic.

[0059] - The primary insulation layer (26) and the secondary insulation layer (28) in the tooth tip (23) region are fused together in a joint area that extends circumferentially around each stator tooth (21).

[0060] - Within the annular joint area, the hybrid structure formed by the first and second plastics has a greater depth (d) than the bottom of the tooth gap.

[0061] 10. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) and the secondary insulation layer (28) are provided with one or more bosses (27; 27a) surrounding the stator tooth (21) and one or more corresponding grooves in the tooth tip (23) region of the corresponding stator tooth (21), the structures being interlocked in a sealing manner, preferably in a comb-like shape.

[0062] 11. The pump according to the foregoing aspect, wherein each boss (27; 27a) has an outer peripheral edge with one or more edges and / or one or more fused edges.

[0063] 12. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) and the secondary insulation layer (28) are interlocked in a comb-like manner in the tooth tip (23) region of the corresponding stator tooth (21), preferably arranged circumferentially around the corresponding stator tooth (21).

[0064] 13. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) extends beyond the primary insulation layer (26) in the tooth gap along the motor axis R direction and covers the primary insulation layer (26) in the tooth end (23) region up to the side of the tooth end (23).

[0065] 14. The pump according to the foregoing aspects, wherein the first plastic and the second plastic differ in terms of polymer composition and / or filler.

[0066] 15. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) and the secondary insulation layer (28) together wrap the coil (25) and achieve electrical insulation between each other and with respect to the stator core (21, 22, 23).

[0067] 16. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) lining the tooth gaps of the stator core (21, 22, 23).

[0068] 17. The pump according to any of the foregoing aspects, wherein the stator (20) has a stator yoke (22) extending annularly around a rotation axis (R), stator teeth (21) protruding from the stator yoke, and a primary insulating layer (26) covering the circumferential portion of the stator yoke (22) opposite to the stator teeth (21).

[0069] 18. The pump according to any of the foregoing aspects, wherein the primary insulation layer (26) completely encloses the stator core (21, 22, 23) to the tooth tip (23) such that only the tooth tip (23) is not covered by the primary insulation layer (26) at least at the sliding surface (24) of its defined operating gap (14).

[0070] 19. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) wraps the stator core (21, 22, 23) and the coil (25) such that only the tooth tips (23) are not covered by the secondary insulation layer (28) at least at the sliding surface (24) of the defined operating gap (14), and the connecting wire (25a) of the coil (25) passes through the secondary insulation layer (28).

[0071] 20. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) completely covers the stator core (21, 22, 23) and the coil (25) up to the tooth tip (23), such that only the tooth tip (23) of the stator core (21, 22, 23) is not covered by the secondary insulation layer (28) at least at the sliding surface (24) of the defined operating gap (14).

[0072] 21. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) fills the gaps between adjacent coils (25) in the stator core (21, 22, 23) around each cooling channel (29).

[0073] 22. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) directly surrounds the corresponding cooling channel (29), thereby directly forming the circumferential wall of the corresponding cooling channel (29).

[0074] 23. The pump according to any of the foregoing aspects, wherein each cooling channel (29) is an axially extending through hole, preferably a straight axial through hole, passing through the secondary insulation layer (28).

[0075] 24. The pump according to any of the foregoing aspects, wherein each cooling passage (29) is closed along the axial length of the operating clearance (14).

[0076] 25. According to any of the foregoing aspects of the pump, wherein the secondary insulation layer (28) directly surrounds each cooling channel (29) along the axial length of the operating gap (14), thereby directly forming the circumferential wall of each cooling channel (29) along the axial length of the operating gap (14).

[0077] 26. The pump according to any of the foregoing aspects, wherein each cooling passage (29) is open radially inward, i.e. toward the motor axis (R), for at least a portion of its axial length.

[0078] 27. The pump according to any of the foregoing aspects, wherein the cooling path for the fluid extends from the cooling path inlet (4a, 4b) located in the high-pressure area within the delivery housing (1, 4), through the operating gap (14) and / or the corresponding cooling passage (29), to the cooling path outlet (16a) located in the low-pressure area within the delivery housing (1, 4).

[0079] 28. According to the pump of the foregoing aspect, the cooling path between the high-pressure area and the low-pressure area branches into a first path that passes through the operating gap (14) and a second path that passes through the corresponding cooling channel (29).

[0080] 29. The pump according to either of the preceding two aspects includes a drive shaft (16) that couples the rotor (10) of a drive motor to an impeller (15) to transmit torque, wherein a cooling passage extends axially through the drive shaft (16).

[0081] 30. The pump according to the foregoing aspect, wherein the drive shaft (16) forms the cooling path outlet (16a).

[0082] 31. The pump according to any of the foregoing aspects, wherein the rotor (10) and impeller (15) of the drive motor are arranged coaxially and can rotate about a common axis of rotation (R).

[0083] 32. The pump according to any of the foregoing aspects, wherein the rotor (10) of the drive motor is connected to the impeller (15) in a manner that prevents relative rotation.

[0084] 33. The pump according to any of the foregoing aspects, wherein - The impeller (15) is arranged in the conveying chamber, and the drive motor (10, 20) is arranged in the motor compartment and connected by the drive shaft (15) to transmit torque.

[0085] - The conveying housing (1, 4) has a back plate (4) on the axial end face facing the motor compartment. - The drive shaft (16) passes through the back plate (4).

[0086] 34. The pump according to any of the foregoing aspects, wherein the rotor (10) of the drive motor and the impeller (15) are arranged coaxially along a drive shaft (16) rotatable about a rotation axis (R), the drive shaft preferably being formed as a hollow shaft.

[0087] 35. The pump according to the preceding aspect, wherein the rotor (10) and impeller (15) of the drive motor are respectively connected to the drive shaft (16) in a manner that prevents relative rotation.

[0088] 36. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) constitutes the motor housing (6).

[0089] 37. The pump according to any of the foregoing aspects includes a motor housing (6) that completely encloses the stator core (21, 22, 23) and coil (25) to the tooth tip (23) such that only the tooth tip (23) remains exposed at least at the sliding surface (24) of the defined operating clearance (14).

[0090] 38. The pump according to the foregoing aspect, wherein the secondary insulation layer (28) constitutes the motor housing (6).

[0091] 39. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) is integrally formed by a one-time molding process, for example as a plastic casting.

[0092] 40. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) is integrally formed by a one-time molding process, for example as a plastic casting, together with the motor housing (6) surrounding the stator core (21, 22, 23) and / or with the wiring housing (7) for connecting to an external system to supply power and / or control the drive motor (10, 20) and / or with the rotary bearing structure (8) for radially supporting the drive shaft (16) which is rotatably fixed to the rotor (10) and / or impeller (15).

[0093] 41. The pump according to the foregoing aspect, wherein the motor housing (6) includes one or more connecting elements (6a) formed in a one-time molding process for connection with the delivery housing (1, 4), and / or includes connecting elements (6b) formed in a one-time molding process for connection with a circuit board (33) of an electro-electronic device equipped with electronic components (34).

[0094] 42. The pump according to either of the first two aspects, wherein the rotary bearing structure (8) includes a central bearing structure surrounding the drive shaft (16) and a connecting bracket extending radially and supporting the central bearing structure on the stator (20).

[0095] 43. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) comprises an assembly geometry (6c) formed in a one-step molding process for mounting the pump to the installation position.

[0096] 44. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) constitutes the motor housing (6), and the delivery housing (1,4) is directly connected to the motor housing (6), preferably directly connected to the secondary insulation layer (28), for example by means of a threaded connection (6a,9).

[0097] 45. The pump according to any of the foregoing aspects, wherein the secondary insulation layer (28) constitutes a wiring housing (7) for one or more electrical connection elements (42, 46), and the stator (20) can be connected to an external power supply system and / or controller, for example by means of a plug-in connection, through the wiring housing (7) and the corresponding connection elements (42, 46).

[0098] 46. ​​A pump according to any combination of aspects 36, 37, 40 and 44, wherein each electrical connection element (42, 46) is embedded in the secondary insulation layer (28) and thereby positioned and fixed relative to the motor housing (6) and / or the wiring housing (7).

[0099] 47. The pump according to the foregoing aspect, wherein each electrical connection element (42, 46) has an internal connection contact (43), an external connection contact (45) and a connection segment (44) connecting the internal connection contact (43) and the external connection contact (45), and the connection segment (44) is embedded in a secondary insulation layer (28), wherein the internal connection contact (43) extends from the secondary insulation layer (28) for connecting to an electromechanical device (34), and the external connection contact (45) extends from the secondary insulation layer (28) for connecting to an external system in the wiring housing (7).

[0100] 48. The pump according to any one of the three aspects mentioned above, wherein the portion (44) of each electrical connection element (42, 46) embedded in the secondary insulation layer (28) has a greater roughness (e.g., corrugation) than the region extending out of the secondary insulation layer, in order to improve the sealing effect of the embedded region.

[0101] 49. The pump according to any of the foregoing aspects includes a rotary bearing structure (8) for rotating support of the rotor (10), wherein the secondary insulation layer (28) and the rotary bearing structure (8) are integrally formed by one molding process, for example as a plastic injection molded part.

[0102] 50. A pump combining the foregoing aspects with aspect 27, wherein the cooling path extends upstream or downstream of the operating gap (14) via one or more channels (8a) of the rotary bearing structure (8).

[0103] 51. A pump according to any of the foregoing aspects in combination with aspects 27 and 33, wherein the cooling path extends upstream of the operating gap (14) and / or the corresponding cooling passage (29) through the back plate (4) of the delivery housing (1, 4).

[0104] 52. A pump that combines any of the foregoing aspects with any of aspects 27 and 29, 33, 34 and 40, wherein the cooling path extends downstream of the operating gap (14) through the drive shaft (16).

[0105] 53. The pump according to any of the foregoing aspects includes an electromechanical device having a circuit board (33) and electronic components (34) disposed thereon for powering and controlling a drive motor (10, 20), wherein a secondary insulating layer (28) is formed with connecting elements (6b) which are in a connected engagement state with the circuit board (33) and fix the circuit board (33) relative to the stator (20) by means of the connected engagement.

[0106] 54. The pump according to the preceding aspect, wherein the connecting element (6b) protrudes in the form of a pin from the stator (20) toward the rear side of the impeller (15) and through the circuit board (33).

[0107] 55. The pump according to either of the preceding two aspects, wherein the connecting element (6b) constitutes a connecting rivet, such that the circuit board (33) is joined to the stator (20) by a riveting connection (e.g., thermal riveting).

[0108] 56. A pump according to any of the foregoing aspects and in conjunction with any of aspects 36, 37, 40 and 44, comprising: - End wall (30), which closes the motor housing (6) at the end face. - Circuit board (33) with motor electronics (34) for controlling and / or powering the stator (20); -The circuit board (33) is arranged on the end face of the end wall (33) that is axially opposite to the stator (20).

[0109] 57. The pump according to the foregoing aspect, wherein the motor housing (6) has connecting elements (6b) formed on the motor housing (6) and passing through the end wall (30) and the circuit board (33) to form connecting rivets, such that the end wall (30) and the circuit board (34) are connected to the motor housing (6) by riveting, for example by thermal riveting.

[0110] 58. The pump according to any of the foregoing aspects, wherein the impeller (15) is a radial impeller.

[0111] 59. The pump according to any of the foregoing aspects, wherein the delivery housing (1, 4) forms a delivery chamber that extends helically around the axis of rotation (R) of the impeller (15).

[0112] 60. A pump according to any of the preceding aspects, wherein the inlet (2) of the delivery housing (1, 4) guides fluid in a direction coaxial with the axis of rotation (R) to the impeller (15).

[0113] 61. A pump according to any of the preceding aspects, wherein the stator (20) surrounds the rotor (10).

[0114] 62. A pump according to any of the preceding aspects, wherein the operating clearance (14) has a radial operating clearance width w, which is measured radially to the axis of rotation (R) and is between the sliding surface (24) of the stator tooth (23) and the circumference of the rotor (10) opposite the operating clearance (14), and the primary insulating layer (26) has a thickness D in the region of the tooth end (23), where w < D or w < 0.5×D.

[0115] 63. A pump according to any of the preceding aspects, wherein - the primary insulating layer (26) and the secondary insulating layer (28) are radially retracted in the tooth gap region behind the sliding surface (24) of the stator tooth (23); or conversely, - the primary insulating layer (26) and the secondary insulating layer (28) are flush - butt - joined with the sliding surface (24) of the stator tooth (23) in the tooth gap region.

[0116] 64. A pump according to any of the preceding aspects, wherein the stator teeth (21) and the secondary insulating layer (28), optionally further including the primary insulating layer (26), together form a stator (21) sliding surface (24, 28a) that extends around the rotor (10) and is at least substantially circular.

[0117] 65. A pump according to any of the preceding aspects, wherein the delivery housing (1, 4) has a back plate (4) that is axially arranged between the impeller (15) and the electric drive motor (10, 20) and is connected to the secondary insulating layer (28) by material bonding, preferably by welding.

[0118] 66. A pump according to any of the preceding aspects, which is used as a cooling medium pump for delivering a water / ethylene glycol mixture and / or a dielectric heat - carrier oil to perform cooling or temperature control (cooling and / or heating) of the following objects: - an internal combustion engine and / or - transmission components of a fuel - driven vehicle transmission system and / or - components of a battery - driven electric vehicle transmission system and / or - battery cells of a motor vehicle traction battery.

[0119] 67. A pump according to any of the preceding aspects, which is constructed as a cooling medium pump for delivering a dielectric heat - conducting oil to directly cool (cool / condition) the battery cells of a motor vehicle traction battery.

[0120] 68. The pump according to any of the foregoing aspects is configured for variable speed control via a vehicle control unit or an engine control unit, and is driven by the vehicle control unit or engine control unit based on one or more measured parameters (e.g., external temperature and / or the temperature of the vehicle component to be regulated).

[0121] 69. A method for manufacturing a stator of an electric drive motor, preferably a method for a stator (20) of a pump drive motor according to any of the foregoing aspects, comprising the following steps: a. A stator core (21, 22, 23) having stator teeth (21) that are at least generally radially oriented along the motor axis (R), the stator teeth having free tooth ends (23) and gaps between the stator teeth (21), a primary insulating layer (26) is formed by injection molding an electrically insulating first plastic, the insulating layer surrounding the stator teeth (21) and preferably lining the gaps; b. Wrap the stator teeth (21) with the primary insulation layer (26) around the wire to form an electric coil (25). c. The stator core (21, 22, 23) and the coil (25) are wrapped with a second layer of insulating plastic by injection molding to form a secondary insulation layer (28), which covers the coil (25) and the stator core (21, 22, 23) and extends to the outside of the coil (25) to the tooth tip (23). d. When spraying the secondary insulation layer (28), a cooling channel (29) is formed in the tooth gap region, penetrating the secondary insulation layer (28) axially, to guide the fluid cooling the stator.

[0122] e. Wherein, the sliding surface (24) at the tooth end (23) forms an operating gap (14) with the rotor (10) of the drive motor, and the sliding surface is not covered by the primary insulation layer (26) and the secondary insulation layer (28).

[0123] 70. According to the method described in the preceding aspect, the injection molding of the primary insulating layer (26) and the secondary insulating layer (28) causes the sliding surface (24) to remain free of the first plastic and the second plastic during the injection molding process.

[0124] 71. The method according to aspect 68, wherein the plastic adhering to the sliding surface (24) after spraying is removed, preferably by cutting.

[0125] 72. The method according to any one of the three aspects mentioned above, wherein the primary insulating layer (26) in the tooth tip (23) region is injection molded in the form of a boss and / or a groove (27) around each stator tooth (21), and each joining geometry (27) contacts and fuses or melts with the second plastic when the secondary insulating layer (28) is injected, such that in the case of fusion, each joining geometry (27) is embedded in the secondary insulating layer (28), or in the case of melting, forms a micro-mixed structure with the first plastic.

[0126] 73. The method according to any one of the four aspects mentioned above, wherein the first plastic and the second plastic differ in terms of polymer composition and / or filler.

[0127] 74. The method according to any one of the five aspects mentioned above, wherein after injection molding with the second plastic, any plastic overflow that may exist on the inner peripheral surface (24, 28a) is removed by a material removal post-processing method, so that the sliding surface (24) at the tooth end (23) does not contain the first plastic and the second plastic. Attached Figure Description

[0128] Embodiments of the invention will now be described with reference to the accompanying drawings. The features disclosed in the embodiments, whether alone or in any combination of features, advantageously constitute the subject matter of the claims and aspects, as well as the foregoing further embodiments.

[0129] Figure 1 The pump according to the invention is shown in a perspective exploded view of the front side of the pump assembly and in a perspective exploded view of the rear side of the pump assembly. Figure 2 This is the first longitudinal section of the pump; Figure 3 This is the second longitudinal section of the pump; Figure 4 This is a cross-sectional view of the pump; Figure 5 yes Figure 4 Details; Figure 6 It is the stator core with coil winding of the electric drive motor of the pump; Figure 7 yes Figure 6 Details; Figure 8 It is a 3D view of the front side of the stator of the drive motor; Figure 9 It is a 3D view of the back of the stator; Figure 10 It is a three-dimensional exploded view of the stator; Figure 11 The stator with electrical connection elements separated from the composite structure is shown; Figure 12 The connection structure for securing a circuit board containing electronic components is shown; Figure 13 The stator tooth gap region shows an improved secondary insulation layer; Figure 14 yes Figure 13 Details; Figure 15 yes Figure 13 It contains details of modified joint geometry; Figure 16 This is a 3D view of the improved motor housing.

[0130] Explanation of reference numerals in the attached figures: 1. Conveyor housing components 1a Connecting element, through hole 2 entrances 3 Exports 4 back panels 4a Cooling path inlet 4b Cooling path inlet 5 seals 6 Motor housing 6a Connecting element, through hole 6b connecting element 6c assembly geometry 7 Wiring housing 8. Rotary bearing structure 8a through hole 9 Fastening components 10 rotors 11 Rotor Support 12-Magnet Support 13 permanent magnets 14 Operating gaps 15 impellers 16 drive shafts 16a Cooling path outlet 17 bearing bushing 18 bearing washers 19 seals 20 stators 21 stator teeth 22 yoke 23 tooth tip 24 inner circumference, sliding surface 25 coils 25A connecting cable 26 Primary insulation layer 26a Maintains geometry 26b maintains geometry 27. Joining geometry 27a Joining Geometry 28 secondary insulation layers 28a inner circumference, sliding surface 29 cooling channels 30 end wall 31 Seals 32 gap filler 33 circuit board 34 Motor Electronic Systems 35 caps 36 Shock absorber, elastomer ring 37 Assembly Structure 38 Assembly Flange 40 contact pads 41 connecting cable 42 Electrical connection elements 43 Internal contact section 44 connecting sections 45 External contact section 46 Electrical connection elements d Height of the joint geometry D. Primary insulation layer thickness R rotation axis w running gap width Detailed Implementation Figure 1 The pump of the present invention is illustrated in two exploded view diagrams. The upper diagram is a perspective view of the front side of the pump assembly, and the lower diagram is a perspective view of the rear side of the pump assembly. Functionally, the pump is divided into three parts: a delivery section equipped with an impeller 15; a drive section equipped with an electric drive motor, including a rotor 10 and a stator 20; and an electronics section equipped with a circuit board 33 and electronic components 34 for powering and controlling the drive motors 10 and 20. These functional parts are integrated and arranged sequentially within a multi-piece housing along the motor axes of the drive motors 10 and 20.

[0131] The conveying section includes a conveying housing having a housing component 1 and a back plate 4, which separates the conveying section from the drive section in the pump assembly state. The housing component 1 has an inlet 2 and an outlet 3 for the fluid to be conveyed. The housing component 1 and the back plate 4 together form a conveying chamber that connects the inlet 2 and the outlet 3. In the assembled state, an annular seal 5 ensures a fluid-tight connection between the housing component 1 and the back plate 4. The housing component 1 can be assembled from multiple parts, but is preferably formed as a single component. An impeller 15 is rotatably mounted in the conveying chamber to convey fluid from the inlet 2 through the conveying chamber to the outlet 3 when rotated by drive motors 10 and 20.

[0132] The pump is designed as a radial centrifugal pump. Therefore, impeller 15 is a radial impeller, and the delivery chamber is a helical chamber. Inlet 2 introduces fluid into the delivery chamber axially, while outlet 3 discharges fluid tangentially. The pump can also be alternatively designed as a positive displacement pump, for example, as an internal shaft positive displacement pump, such as a vane pump or a ring gear pump. However, a centrifugal pump form is preferred, especially in applications where it is used as a coolant pump.

[0133] The drive section includes a motor housing 6 that surrounds and is fixedly connected to the stator 20. A wiring housing 7 is formed on the motor housing 6. The wiring housing 7 surrounds electrical contact points for connecting the drive motor (stator 20 in this embodiment) to an external power source and / or an external controller (e.g., a motor controller for a vehicle). The wiring housing 7 surrounds these wiring contacts and is configured to plug into corresponding connectors.

[0134] In the assembled state of the pump, the rotor 10 is housed within a motor compartment surrounded by the motor housing 6. A backplate 4 separates the motor compartment from the delivery chamber. The drive motors 10 and 20 are exemplarily designed as internal rotors. Therefore, the rotor 10 is surrounded by the stator 20. The rotor 10 is non-rotatably connected to the drive shaft 16. The drive shaft 16 constitutes the motor shaft of the drive motors 10 and 20. Bearing bushings 17 and bearing washers 18 provide rotational support for the drive shaft 16, and thus also for the rotational support of the rotor 10. In the assembled state, an annular seal 19 provides a seal between the rotor 10 and the bearing washers 18.

[0135] End wall 30 closes the motor compartment axially away from the conveyor section at its rear. End wall 30 serves as a partition between the motor compartment and the electronics compartment, where electronic components 34 are mounted on circuit board 33, as shown in the lower figure. An annular seal 31 is provided between the motor housing 6 and end wall 30 to ensure fluid-tight isolation between the electronics compartment and the motor compartment. A thin film-like gap filler 32 is provided between end wall 30 and circuit board 33. In the assembled state, the disc-shaped end wall 30, the film-like gap filler 32, and the circuit board 33 form an axially stacked structure. Cover 35 closes the rear of the electronics compartment.

[0136] In the assembled state, the conveyor housings 1 and 4 are axially fitted together with the motor housing 6 and connected to each other in a non-movable manner. For example, they are joined by a threaded connection. To manufacture the connection structure, the conveyor housings 1 and 4 are equipped with connecting elements 1a, and the motor housing 6 is equipped with connecting elements 6a. These elements are fixedly connected to each other by connecting elements 9 (e.g., screw elements). The connecting element 1a is a straight axial channel formed in the housing component 1. The connecting element 6a is an axial groove or channel formed correspondingly to the connecting element 1a on the motor housing 6. If the connecting element 9 is designed as a threaded element as in the embodiment, the connecting element 6a can be equipped with a matching internal thread. However, it is advantageous that the connecting element 9 is inserted into the connecting element 6a, thereby ensuring that the conveyor housing 1 is firmly fixed to the motor housing 6.

[0137] The layered structure consisting of end wall 30, gap filler 32, and circuit board 33 is connected by threads or preferably as described below. Figure 12 The motor housing 6 is fixedly connected to the electronic compartment using a riveting-like method. After the layer structures 30, 32, and 33 (especially the circuit board 33) are arranged and fixed, the electronic compartment is sealed with a cover 35. The cover 35 can be connected to the motor housing 6 preferably by a material bonding method, such as friction welding.

[0138] For mounting a pump, such as in the motor compartment of an internal combustion engine, a pure electric vehicle, or a hybrid internal combustion engine and electric vehicle, a mounting structure 37 is provided. The mounting structure 37 can preferably be connected to the pump via a shock absorber 36. In this embodiment, the shock absorber 36 is formed as a damping ring, such as an elastomer ring. The shock absorber 36 is fitted onto the outer circumference of the motor housing 6 and advantageously surrounds the motor housing 6 with a certain elastic tension. In this embodiment, the shock absorber 36 is fitted relative to the inner circumference of the outer circumference of the motor housing 6 with a certain fit clearance. The mounting structure 37 forms a sleeve. It includes two relatively movable components, in this embodiment, two semi-shell-shaped structural members, which are fitted to the shock absorber 36 from the outside and tightened with a certain tension by suitable fasteners (e.g., threaded connections), thereby mounting the motor housing 6 and the entire pump in the mounting position via the shock absorber 36. The mounting structure 37 may have one or more connectors 38 by which the mounting structure 37 and the pump can be secured in the mounting position, for example, in the motor compartment of a motor vehicle.

[0139] Figure 2The pump is shown in its central longitudinal section in its assembled state, extending the drive shaft 16 and the axis of rotation R of the rotor 10. A helical delivery chamber is visible, connecting the centrally axial inlet 2 to the tangential outlet 3. The drive chamber is closed by a back plate 4 on its rear side facing the drive motors 10 and 20. Within the delivery chamber, the impeller 15 can rotate about the axis of rotation R. During rotational drive, fluid is drawn in through inlet 2 and flows toward the end face of the impeller 15, deflecting radially outward as is known in radial delivery pumps, ultimately exiting tangentially at the outer circumference of the impeller 15 and discharging through outlet 3. The back plate 4 is axially opposed to the rear side of the impeller 15 and forms a seal with the impeller 15, such as a labyrinth seal, to separate the delivery chamber from the motor housing. The back plate 4 can form an axial press fit with the delivery housing component 1 and the motor housing 6, i.e., axially pressed against the motor housing 6. If the backplate 4 is made of plastic, it can be additionally or alternatively welded to the motor housing 6, for example by ultrasonic welding, laser welding, mirror welding, rotary welding or vibration welding.

[0140] The impeller 15 is fixedly connected to the drive shaft 16, and is also fixedly connected to the rotor 10 via the drive shaft. The rotor 10 and the impeller 15 are arranged coaxially with each other along the drive shaft 16.

[0141] The motor housing 6 forms a rotary bearing structure 8 for radial support of the drive shaft 16, which in this embodiment serves as radial support for the rotating assembly consisting of the rotor 10, impeller 15, and drive shaft 16. The rotary bearing structure 8 includes a sleeve-shaped structural region surrounding an axial section of the drive shaft 16 to radially support the drive shaft 16, thereby supporting the rotor 10 and impeller 15. This axial section extends between a front shaft section and a rear shaft section, wherein the drive shaft 16 and impeller 15 are connected in an anti-rotational manner in the front shaft section, and the drive shaft 16 and rotor 10 are connected in an anti-rotational manner in the rear shaft section. In addition to the rotary bearing structure 8, the bearing arrangement of the drive shaft 16 also includes a bearing bushing 17 that extends into the sleeve-shaped structural region of the rotary bearing structure 8 and is preferably connected to the rotary bearing structure 8 without rotation. Furthermore, the bearing arrangement also includes a bearing gasket 18 for axial support of the rotor 10. Figure 1 ), and a seal 19 extending around the drive shaft 16 and disposed between the rotor support 11 and the bearing gasket 18 ( Figure 1 ).

[0142] The rotor 10 includes a rotor support 11 fixedly connected to and extending radially outward from the drive shaft 16, a magnet support 12, and a plurality of permanent magnets 13. These permanent magnets are distributed on the rotor support 11 around the rotation axis R and are held in position by the magnet support 12. The magnet support 12 may preferably be formed as a lamination group composed of axially stacked rotor laminations.

[0143] The rotary bearing structure 8 has a radially extending, for example, annular, connecting bracket that rigidly connects the sleeve-shaped structural region to a radially outer region of the motor housing 6. The connecting bracket of the rotary bearing structure 8 extends radially outward and inward toward the drive shaft 16 until it reaches the sleeve-shaped structural region, which extends into the annular gap between the drive shaft 16 and the rotor 10. This results in a nested, space-saving arrangement of the drive shaft 16, the rotor 10, and the rotary bearing structure 8. Furthermore, the drive shaft 16 is advantageously arranged axially to provide radial support between its rotationally fixed connection to the rotor 10 and its rotationally fixed connection to the impeller 15.

[0144] The stator 20 surrounds the rotor 10. The stator 20 has stator teeth 21 carrying electrical coils 25, a primary insulation layer 26 between the stator teeth 21 and the coils 25, and a secondary insulation layer 28. The primary insulation layer 26 and the secondary insulation layer 28 fluid-tightly enclose the coils 25. The coils 25 can be energized through contact plates 40 and connected electrical connection wires 25a. Between the rotor 10 and the stator 20, a running gap 14 extends circumferentially along the axis of rotation R, its radially inner side defined by the rotor 10 and its radially outer side defined by the stator 20.

[0145] Drive motors 10 and 20 are designed as wet-running units. The fluid conveyed by impeller 15 is used to cool drive motors 10 and 20. For this purpose, a small branch from the high-pressure fluid region is diverted from the conveyed fluid flow, directed through the motor housing to cool drive motors 10 and 20, and preferably also including end walls 30, and through which the circuit board 33 with electronic components 34 is cooled, before finally being returned to the low-pressure fluid region. The diverted branch is driven by the pressure difference formed between the two fluid regions during fluid conveying. The descriptions of "higher pressure" and "lower pressure" are intended only to indicate that a pressure difference exists between such fluid regions, sufficient to generate and sustain partial flow. Preferably, the diversion is branched off from the main flow conveyed by impeller 15 in the conveying housings 1 and 4, and / or returns to the main flow in the conveying housings 1 and 4. This diversion can be particularly downstream of impeller 15 and / or upstream of impeller 15.

[0146] Figure 3A cooling path is visible, along which some fluid flows through the motor nacelle. The cooling path extends from the cooling path inlet 4a, located in the high-pressure fluid region, to the motor nacelle, where it leads to the operating gap 14, passes through the operating gap 14 to the back of the rotor 10, and then extends from there via the drive shaft 16 to the cooling path outlet 16a, leading to the low-pressure fluid region. The cooling path inlet 4a is positioned upstream of the cooling path outlet 16a on the main flow path conveyed by the impeller 15, thus establishing a pressure differential sufficient to drive the branch section. The cooling path inlet 4a passes through the operating gap formed by the impeller 15 and the back plate 4. Through the cooling path inlet 4a, leaking fluid enters the motor nacelle from the outer circumference of the impeller 15. Downstream of the operating gap 14, the fluid enters the motor nacelle and contacts the end wall 30, cooling the circuit board 33 and, consequently, the electronic components 34 through the end wall 30 and the gap filler 32. The cooling path outlet 15a opens towards the inlet 2 on the front side of the impeller 15.

[0147] The cooling path extends through the operating gap 14 and passes through one or more channels 8a of the rotary bearing structure 8. A corresponding through hole 8a extends upstream of the operating gap 14 through the connecting bracket of the rotary bearing structure 8.

[0148] The drive shaft 16 is designed as a hollow shaft. Fluid located between the rotor 10 and the end wall 30 within the motor nacelle flows into the drive shaft 16 from its rear end and exits at its front end into a low-pressure fluid region. In this embodiment, the drive shaft 16 extends through the impeller 15, and a cooling path outlet 16a is formed at the front end face of the drive shaft 16. In a variation, the impeller 15 may constitute a cooling path outlet.

[0149] The drive motors 10 and 20 are cooled not only from the operating gap 14. To enhance the cooling effect, additional fluid from the high-pressure fluid region is guided 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 diverted fluid can merge with the fluid that has passed through the operating gap 14 in the motor compartment, and is also guided back to the low-pressure fluid region at the cooling path outlet 16a via the drive shaft 16.

[0150] Compared to using either of these measures alone, the combination of operating gap cooling and stator internal cooling achieves more efficient cooling and enhances on-demand heat dissipation. This is attributed to a combination of factors. Coolant flow rate can be increased and more precisely adapted to demand. Furthermore, the area of ​​the stator 20 involved in heat exchange is increased, and these areas can be selected more precisely according to requirements. Additionally, the ratio of operating gap flow to cooling channel flow can be used to optimize cooling performance, thereby more accurately matching the required cooling effect.

[0151] In an exemplary embodiment, cooling channel 29 is connected to the high-pressure fluid region via one or more channels 4b passing through the back plate 4. These one or more channels 4b collectively constitute the cooling path inlet. Therefore, the fluid is cooled not only by the inevitable leakage through the impeller 15 operating gaps, but also by the fact that the fluid reaches the drive motors 10, 20 for cooling.

[0152] The exemplary embodiment's cooling path comprises two parallel sub-paths that branch independently in the high-pressure fluid region and converge within the motor nacelle: one located downstream of the operating gap 14 and cooling channel 29, and the other upstream of or at the drive shaft 16. In a variant, the two cooling paths, one through the operating gap 14 and the other through the internal cooling channel 29 of the stator 20, can each extend independently from the high-pressure fluid region to the low-pressure fluid region. In other variants, the cooling path through the motor nacelle may also branch into two paths only within the motor nacelle. However, the supplementary cooling fluid flowing in through the additional cooling path inlet 4b replenishes the unavoidable leakage fluid flowing through the cooling path inlet 4a, allowing this independent additional cooling path inlet to more precisely match actual cooling requirements in a structurally simple manner.

[0153] like Figure 4 and Figure 5 As shown, the stator 20 includes a stator core having a plurality of stator teeth 21 extending radially from an annular stator yoke 22 surrounding the axis of rotation R to free tooth tips 23. Wires are wound around the stator teeth 21 to form an electrical coil 25. The stator teeth 21 serve as pole shoes. The stator cores 21, 22, and 23 are preferably configured as laminations consisting of axially stacked stator laminations. The stator laminations may have… Figure 4 The visible cross-section.

[0154] The stator 20 includes the aforementioned primary insulating layer 26, which surrounds each stator tooth 21 and covers the gaps between the stator teeth 21. The primary insulating layer 26 is formed between the stator cores 21, 22, 23 and the coil 25 to provide electrical insulation for the coil 25. The primary insulating layer 26 acts like a skin covering the stator cores 21, 22, 23. It advantageously encloses the stator cores 21, 22, 23, leaving only the circumferential surface defining the operating gap 14 on the stator cores. The sliding surface 24 at the tooth tip 23 remains free. Preferably, the primary insulating layer 21 is slightly recessed at the tooth tip 23 behind the sliding surface 24, but otherwise preferably completely encloses the stator cores 21, 22, 23, thus also covering their end faces and outer circumference. If the stator cores 21, 22, 23 employ a laminated structure, the primary insulating layer 26 prevents fluid seeping between the stator laminations from contacting the coil 25.

[0155] Secondary insulating layers 28 are formed in the gaps between the stator cores 21, 22, and 23, serving to electrically isolate the coil 25 from the fluid flowing through the operating gap 14. The primary insulating layer 26 and the secondary insulating layer 28 together enclose the coil 25, isolating it from fluid contact. Therefore, the secondary insulating layers 28 also surround the coil 25 at both end faces. Furthermore, they cover the outer circumference of the stator cores 21, 22, and 23. Preferably, the secondary insulating layers 28 completely and fluid-tightly enclose the stator cores 21, 22, and 23 and the coil 25, except for the sliding surfaces 24 of the stator teeth 21 defining the operating gap 14. Electrical connection wires 24a pass through only the secondary insulating layers 28, but they are fluid-tightly surrounded by the secondary insulating layers 28. The sliding surfaces 24 on the tooth tips 23 of the stator teeth 21 are also not covered by the insulating material of the secondary insulating layers 28. Preferably, the secondary insulation layer 21 is slightly recessed at the tooth tip 23 behind the circumferential surface of the corresponding stator tooth 24, but otherwise, the insulation layer preferably completely covers the stator cores 21, 22, and 23.

[0156] Since neither the primary insulation layer 26 nor the secondary insulation layer 28 covers the sliding surface 24 of the stator teeth 21 that defines the operating gap 14, that is, the sliding surface 24 of each stator tooth 14 remains uncovered by the insulation layers 26 and 28, therefore Figure 5 The width of the running clearance 14 marked with "w" may have a smaller advantage. The running clearance width w is the net distance between the sliding surface 24 of each stator tooth 21 and the rotor 10, measured in the radial direction. If the running clearance width w varies circumferentially, for example, in this embodiment, the rotor 10 has a radially convex circumferential region, then the width w should be measured at the radially narrowest point of the running clearance 14.

[0157] In an advantageous embodiment, the circumferential surfaces 24 of the stator core 21 are exposed. However, in principle, they can be coated with a protective varnish, such a thin layer as to not cause a significant increase in the operating clearance width w. In any case, if a protective varnish is applied, it is also thinner than the skin-like primary insulation layer 26.

[0158] Cooling channels 29 axially pass through the secondary insulation layer 28 in the gaps between the stator cores 21, 22, and 23. Specifically, in each gap, a cooling channel 29 extends through the secondary insulation layer 28. The secondary insulation layer 28 surrounds each cooling channel 29 infinitely and directly forms the channel wall of the corresponding cooling channel 29. The cooling channels 29 are used to enhance the cooling of the coil 25 from the corresponding gap toward the adjacent stator teeth 21. Therefore, the coil 25 and the stator cores 21, 22, and 23 can be cooled deeply and effectively, starting from both the operating gap 14 and the cooling channels 29. If the stator cores 21, 22, and 23 adopt a lamination structure, fluid can penetrate from the operating gap 14 into the interior of the lamination assembly between the stator laminations and directly reach the primary insulation layer 26, thereby achieving a more efficient cooling effect.

[0159] The primary insulation layer 26 and the secondary insulation layer 28 together prevent fluid from contacting the coil 25. To shield the coil 25, the primary insulation layer 26 and the secondary insulation layer 28 are continuously connected in contact around each stator tooth 21 in the tooth tip 23 region, forming a fluid-impermeable seal. Therefore, the secondary insulation layer 28 can apply a specific pressure towards the stator cores 21, 22, and 23 upon contact, thereby achieving the desired seal through force closure. Alternatively or supplementarily, the insulation layers 26 and 28 can be joined by material bonding, such as by adhesive bonding and / or fusion of contact surfaces, or by using an adhesive. In the tooth tip 23 region, the insulation layers 26 and 28 can have an infinitely looping engagement geometry around each stator tooth 21, these structures interlocking to improve the seal through form fit. This connection feature can also be combined with material bonding and / or force bonding. The two insulators 26 and 28 can be joined to each other at any point of contact by material bonding and / or force bonding. In a preferred embodiment, the primary insulation layer 26 and the secondary insulation layer 28 are interconnected by a specific bonding structure at least within a special bonding area, which extends in a ring around each stator tooth 21 and is located between the coil 25 and the operating gap 14.

[0160] Figure 6 The stator cores 21, 22, and 23, along with their coils 25 and primary insulation layer 26, are shown, but the secondary insulation layer 28 has not yet been fabricated. Figure 7 As shown Figure 6Enlarged detail of the tooth tip 23. The primary insulation layer 26 wraps around the stator cores 21, 22, and 23 in a skin-like manner up to near the tooth tip 23. "Up to near the tooth tip" means that the primary insulation layer 26 wraps around the stator cores 21, 22, and 23 in the direction towards the tooth tip 23, extends beyond the coil 25, and provides sufficient contact area between the coil 25 and the tooth tip 23 for a fluid-tight connection with the secondary insulation layer 28 to be manufactured. At the tooth tip 23, at least the sliding surface 24 remains uncovered by the primary insulation layer 26.

[0161] To ensure enhanced shielding security for coil 25, the primary insulation layer 26 features a unique engagement characteristic in the aforementioned engagement region (extending around each stator tooth 21 between coil 25 and operating gap 14): each stator tooth 21 is provided with multiple annular engagement geometries 27 extending side-by-side around the stator tooth 21, shaped as infinitely encircling rib-like protrusions extending from the stator tooth 28. Each engagement geometry 27 protrudes beyond half the thickness of the primary insulation layer 25 from the otherwise macroscopically smooth surface.

[0162] exist Figure 5 The thickness D of the primary insulating layer 26 and the height d of the bonding geometry 27 are indicated. Accordingly, each bonding geometry 27 has a height d measured relative to an adjacent smooth surface region, which is greater than 0.2D or greater than 0.4D. Advantageously, the height d is less than 3D or less than 2D.

[0163] The primary insulation layer 26 is made of electrically insulating plastic. Good thermal conductivity of the plastic is advantageous. The plastic can be a pure polymer material, or preferably a filled polymer material. This plastic can be thermoplastic or thermosetting. The primary insulation layer 26 can be manufactured, in particular, by injection molding. For this purpose, the stator cores 21, 22, and 23 are placed in an injection mold and encapsulated with plastic. Upon solidification, the plastic forms the primary insulation layer 26, in a primary injection-molded encapsulation form. The connecting geometry 27 is preferably formed directly within the mold during the injection molding process.

[0164] Before injection molding, contact piece 40 (attached) Figure 2 , 9 (10) can also be positioned in an injection mold, so that it is encased in plastic by the primary insulation layer 26 along with the stator core 21, and thereby fixed in the desired position. Contact piece 40 in Figure 6 Not shown. Only the retaining geometries 26a, made of plastic and consisting of primary insulating layers 26, are visible. These geometries each surround the retaining section of the contact piece 40, wherein after the primary insulating layer 26 is formed, each contact piece extends outward at its retaining geometry 26a to connect to electromechanical equipment, and remains free in its inner section to connect to the coil 25. Figure 2Two contact pieces 40 can be seen in the middle. Figure 9 In the middle, they protrude from the secondary insulation layer 28. Figure 10 The stator core with injection-molded primary insulation layer 26 and fixed contact piece 40 are shown.

[0165] The stator cores 21, 22, and 23 can be completely encased in the plastic of the primary insulation layer 26 during injection molding and then re-exposed at their circumferential surfaces 24 through an additional process. However, during injection molding, the circumferential surfaces 24 preferably remain unaffected by the plastic of the primary insulation layer 26. Therefore, it would be advantageous if the primary insulation layer 26 were slightly recessed behind the circumferential surfaces 24 (i.e., the subsequent sliding surfaces 24) during spraying, as detailed in the appendix. Figure 5 and 7 The details are most clearly visible in the display. This helps prevent the formation of so-called webbed tissue.

[0166] To manufacture coil 25, stator cores 21, 22, and 23 (in this embodiment, injection molded) with primary insulation layer 26 are wound with conductive material. The resulting coil 25 can be connected via contact piece 40 (with...) Figure 2 , 9 When energized (10), these contact pieces extend from the retaining geometry 26a on the outer circumference of the stator yoke 22 and are connected to the coil 25 via electrical connection wires 25a. The coil 25 is connected to the contact pieces 40 before the secondary insulation layer 28 is fabricated. For example, the connection can be made by resistance welding.

[0167] Along with the primary insulation layer 26, a retaining geometry 26b for connecting the wire 25a can also be formed, suitably made of the plastic of the primary insulation layer 26. The retaining geometry 26b is shaped such that the connecting wire 25a of the coil 25 rests against the outer circumference of the retaining geometry 26a and extends circumferentially along the outer circumference to its corresponding contact piece 40. The contact piece 40 can be injection molded with the plastic of the primary insulation layer 26 during its formation, thereby securing it in place.

[0168] The stator cores 21, 22, and 23, with coils wound around them and equipped with contact pieces 40, will be placed in another injection mold for secondary injection molding in a subsequent process to form the secondary insulation layer 28. This time, the secondary insulation layer 28 is covered with plastic material, ensuring that the coils 25 are completely and reliably sealed, effectively preventing the infiltration of fluids from the motor compartment. After the second injection molding, only the contact pieces 40 still protrude from the secondary insulation layer 28.

[0169] The secondary insulating layer 28 is also made of electrically insulating plastic. It is more advantageous if the plastic used for the secondary insulating layer 28 has good thermal conductivity. The plastic of the secondary insulating layer 28 can be a pure polymer material, or more preferably a filled polymer material. This plastic can be a thermoplastic or thermosetting plastic.

[0170] Figure 8 and Figure 9 The image shows the state of the stator 20 after it has been covered with plastic containing the secondary insulation layer 28. Figure 8 The stator 20 is oriented towards the impeller 15 ( Figure 2 The 3D diagram in front of it, and Figure 9 This is a perspective view of the stator 20 facing away from the impeller 15. Through this secondary injection molding, the coil 25 and the stator cores 21, 22, and 23 are completely sealed and encased in plastic by the secondary insulation layer 28, thus exposing only the tooth tips 23 or at least their circumferential direction. The sliding surface 24 should remain separate from the secondary insulation layer 28. During the secondary injection molding process, the motor housing 6, the wiring housing 7, and the rotating bearing structure 8 are integrally molded from the same plastic, along with the secondary insulation layer 28.

[0171] The rotary bearing structure 8 has a central sleeve-shaped structural area, and an annular disc-shaped connecting bracket that connects the sleeve-shaped structural area to the outer ring area of ​​the motor housing 6. Also clearly visible are the contact pieces 40 extending axially from the secondary insulation layer 28 on the back side of the stator 20, such that they extend into the electronic component chamber when the pump is assembled.

[0172] The stator 20 also includes connecting elements 6b, which protrude axially in a pin-like manner from the back of the stator 20. The connecting elements 6b are also molded directly from the plastic during the plastic injection molding process of the secondary insulation layer 28. They are used to position and secure relative to the stator 20 to the end wall 30, the gap filler 32, and the circuit board 33. Figure 1 A layered structure composed of ).

[0173] On one side of the stator 20 forming the wiring housing 7, an electrical connection element 42 extends outward from the back of the stator 20 or the pump's electronics compartment to the wiring housing 7. An internal contact section 43 and an external contact section 45 are visible on the connection element 42. The internal contact section 43 extends freely axially from the back of the stator, enabling it to make an electrical connection with a corresponding electrical connection point on the circuit board 33. The external contact sections 45 each extend freely axially within the wiring housing 7, allowing connection via corresponding interfaces to an external power source and / or controller (e.g., a motor controller in a motor vehicle, especially an automobile) through a corresponding plug-in connection.

[0174] exist Figure 10 and Figure 11 The diagram specifically shows connection elements for connecting the stator 20 to an external power supply and control system. This includes contact pieces 40 and connecting elements 42 and 46. Figure 10 In the image, the stator core with coils wound around it and the secondary insulation layer 28, which also forms the motor housing 6, are shown separately. Figure 10The winding stator core is shown after the contact pieces 40 are connected. In this state, the winding stator core is molded by plastic covering of the secondary insulation layer 28, forming a motor housing 6 with a wiring housing 7 and a rotary bearing structure 8.

[0175] Before injection molding with the plastic of the secondary insulation layer 28, connecting elements 42 and 46 are positioned in the injection mold relative to the wound stator core and are also encapsulated with the plastic of the secondary insulation layer 28, so that after injection molding, they are embedded in the plastic of the secondary insulation layer 28 and fixed in place, with only their inner contact section 43 and outer contact section 45 protruding freely from the plastic body. Connecting elements 42 and 46 are U-shaped in their respective side views, having two side arms, one forming the inner contact section 43 and the other forming the outer contact section 45, and an intermediate connecting section 44 connecting the two side arms. After the secondary insulation layer 28 is formed, the motor housing 6 is also formed, with each connecting leg 44 extending radially outward from the corresponding inner contact section 43 to the wiring housing 7, where it transitions into the outer contact section 45, which protrudes from the plastic substrate in the wiring housing 7.

[0176] Connecting elements 42 and / or 46 may have a rougher surface in their connecting section 44 region than their contact sections 43 and 45. For example, at the respective connecting sections 44, the surface may be corrugated or treated by other means such as embossing or laser structuring. The greater roughness improves the adhesion between the plastic and the embedded connecting section 44 and enhances the sealing effect along the embedded length.

[0177] exist Figure 12 In the detailed view, it can be seen that the end wall 30, the gap filler 32, and the circuit board 33 are positioned and fixed to the motor housing 6 by this connection method. In the installed state shown, the connecting element 6b passes through the layer structures 30, 32, and 33, which have corresponding channels for this purpose. The connecting element 6b is used to form a riveted connection. During assembly, the end wall 30, the gap filler 32, and the circuit board 33 are mounted on the back of the stator 20. The positioning of the motor housing 6 is such that the connecting element 6b passes through the corresponding channels of the layer structures 30, 32, and 33, and each protrudes beyond the circuit board 33 with a head section. Subsequently, the head sections are fused or welded on, so that the connecting element 6b locks the circuit board 33 from the rear, thereby fixing it to the motor housing 6.

[0178] Figure 13The improved stator 20 is shown in the backlash region in a cross-section. The first improvement is that the stator teeth 21 and the secondary insulation layer 28 together form a sliding surface that remains at least substantially smooth circumferentially around the motor axis R. This surface is formed by alternating combinations of the sliding surfaces 24 of the stator teeth 21 and the sliding surfaces 28a of the secondary insulation layer 28 circumferentially. Due to the at least substantially smooth composite sliding surfaces 24, 28a, eddies in the fluid within the operating gap 14 are reduced or completely avoided.

[0179] exist Figure 14 The image shows a magnified view of the tooth tip 23 region of stator tooth 21 and a region of the adjacent tooth gap. This involves... Figure 13 The detail marked X. In the enlarged view, it can be seen that the sliding surface 28a formed by the secondary insulation layer 28 does not precisely and smoothly connect to the sliding surface 24 of the stator tooth 21, but is slightly recessed from it. Therefore, the composite sliding surfaces 24 and 28a each have flat grooves in the tooth gap region. In the axial direction, i.e., parallel to the motor axis R, these grooves can extend through the entire length of the secondary insulation layer 28, or be confined at the two end faces of the stator core, thus forming a groove structure. However, the radial offset between the sliding surfaces 24 and 28a, and the resulting non-uniformity of the composite sliding surfaces 24 and 28a, is significantly smaller than... Figure 4 and Figure 5 The situation is illustrated in the embodiments of the two insulating layers 26 and 28.

[0180] The second improvement involves extending the secondary insulation layer 28 radially inward, i.e., towards the motor axis R, beyond and around the primary insulation layer 26. Viewed from the bottom of the tooth gap, they interlock and extend to the side of the stator tooth 21 in the tooth tip 23 region. This geometric modification improves the sealing effect with the operating gap 14. In principle, the primary insulation layer 26 could extend radially inward to the sliding surface 28a to form the sliding surface 28a together with the secondary insulation layer 28. However, forming the sliding surface 28a solely through the secondary insulation layer 28 not only facilitates sealing around the operating gap 14 but also results in a smooth sliding surface 28a.

[0181] exist Figure 15In the embodiment, the joining geometry is modified relative to joining geometry 27 and is therefore referred to as joining geometry 27a. The improvement lies in that the bosses of the primary insulating layer 26 extending into or embedded in the secondary insulating layer 28 have flat outer circumferential edges at their outer ends. The bosses of joining geometry 27 each taper at their outer circumferential edges, i.e., each forming a pointed tip in the illustrated cross-section; while the bosses of the improved joining geometry 27a each form two edges at their outer circumferential edges. In this embodiment, they are rectangular in the illustrated cross-section. This results in a sealing effect similar to a labyrinth seal, the only difference being that no relative rotational movement occurs between the insulators 26 and 28. The bosses of the joining geometry can also take other shapes, but are preferably those with one or more edges, such as a single pointed tip or two edges located at the outer circumferential edge. The joining geometries, such as joining geometries 27 and 27a, with their multiple boss designs and the resulting comb-like engagement, have ensured the formation of a favorable long sealing gap between the insulators 26 and 28. Forming a single tip or multiple edges, each with its own tip, is particularly advantageous for sealing because the plastic of the primary insulation layer 26 melts in the tip or edge regions during the overmolding process through the plastic of the secondary insulation layer 28. This creates a material bond in the form of a molten zone, at least locally at each tip or edge, resulting in a better sealing joint area. For completeness, it should be noted that the molten zone preferably loops infinitely around the tip or edge of the corresponding notch of each stator tooth 21.

[0182] Figure 16 The improved motor housing 6 is shown in a perspective view, facing the rear opposite to the conveyor chamber. As previously described, the motor housing 6 is formed directly during the molding of the secondary insulation layer 28, and can in particular be made of the same plastic as the secondary insulation layer 26. (Compared to...) Figures 1 to 12 Unlike the previous embodiment, the motor housing 6 has an additional function. Specifically, a mounting geometry 6c is additionally formed on the motor housing 6. The mounting geometry 6c is designed for bolt-mounting the pump. The mounting geometry 6c includes multiple mounting flanges that protrude from the body of the motor housing 6, forming so-called independent fixing or mounting flanges. Each mounting flange has through holes for fasteners (e.g., fixing screws). The mounting geometry 6c is an integral part of the secondary injection molding or secondary insulation layer 28. It is formed directly together with the secondary insulation layer 28 during its formation.

[0183] The assembly geometry 6c contains multiple channels, each for a fastener, such as a fixing screw. To achieve vibration damping, the assembly geometry 6c may include resilient connecting elements arranged in the channel areas, which are connected to the mounting flange, for example, by form-locking and / or force-locking methods.

Claims

1. A pump for conveying fluids, such as cooling fluids and / or lubricating fluids, said pump comprising: A delivery housing (1, 4) having an inlet (2) and an outlet (3) for the fluid. An impeller (15) is rotatable within the conveying housing (1, 4) for conveying the fluid from the inlet (2) to the outlet (3). as well as An electric drive motor (10, 20) includes a rotor (10) and a stator (20), the rotor (10) being rotatable about a motor axis (R) and connected to the impeller (15) to drive the impeller, the stator (20) and the rotor (10) together forming an operating clearance (14) around the motor axis (R), the stator (20) comprising: Stator core (21, 22, 23) having stator teeth (21) and tooth gaps, the stator teeth (21) pointing at least substantially radially toward the motor axis (R), and the tooth gaps remaining between the stator teeth (21); The wire is wound around the stator teeth (21) to form an electrical coil (25). A primary insulating layer (26), formed between the corresponding stator tooth (21) and the coil (25) surrounding the stator tooth (21), serves to electrically insulate it; and A secondary insulating layer (28) is formed in the tooth gap for electrically insulating adjacent coils (25). Each of the stator teeth (21) includes a sliding surface (24) at the tooth tip (23), the sliding surface facing the rotor (10) radially and being disposed opposite to the rotor through the running gap (14), and the sliding surface does not cover the primary insulation layer (26) and the secondary insulation layer (28). Furthermore, in each of the one or more of the tooth gaps, a cooling channel (29) through which coolant can flow extends axially through the secondary insulation layer (28).

2. The pump according to claim 1, wherein, The primary insulation layer (26) and the secondary insulation layer (28) are connected circumferentially around each stator tooth (21) at least in the tooth tip (23) region in a fluid-impermeable manner, preferably by a material bonding method, thereby isolating the coil (25) from the operating gap (14).

3. The pump according to claim 1 or 2, wherein, In the tooth tip (23) region of the corresponding stator tooth (21), the primary insulation layer (26) and the secondary insulation layer (28) include one or more engagement geometries (27; 27a) extending circumferentially around the corresponding stator tooth (21), the geometries interlocking to form an annular engagement region that is fluid-tight upon engagement.

4. The pump according to any one of claims 1-3, wherein, The primary insulating layer (26) and the secondary insulating layer (28) form a joint area extending annularly around each of the stator teeth (21) in the tooth tip (23) region, wherein the interlocking depth between the microstructure of the primary insulating layer (26) and the microstructure of the secondary insulating layer (28) in the joint area is greater than the depth of the bottom of the tooth gap.

5. The pump according to any one of claims 1-4, wherein, The primary insulating layer (26) is made of a first plastic, and the secondary insulating layer (28) is made of a second plastic; The primary insulating layer (26) and the secondary insulating layer (28) are fused together in a circumferentially extending engagement area around each stator tooth (21) in the tooth tip (23) region; and Within the annular joint area, the hybrid structure formed by the first plastic and the second plastic has a greater depth (d) than the bottom of the tooth gap.

6. The pump according to any one of claims 1-5, wherein, The primary insulation layer (26) completely encloses the stator core (21, 22, 23) to the tooth tip (23) such that only the tooth tip (23) is not covered by the primary insulation layer (26) at least at the sliding surface (24) that defines the operating gap (14).

7. The pump according to any one of claims 1-6, wherein, Each of the cooling channels (29) is a through hole extending axially through the secondary insulating layer (28), preferably a straight axial through hole.

8. The pump according to any one of claims 1-7, wherein, The cooling path for the fluid begins at the cooling path inlet (4a, 4b) in the delivery housing (1, 4) leading to the high-pressure area, passes through the operating gap (14) and / or the corresponding cooling channel (29), and extends to the cooling path outlet (16a) in the delivery housing (1, 4) leading to the low-pressure area.

9. The pump according to any one of claims 1-8, wherein, The rotor (10) and impeller (15) of the drive motor (10, 20) are arranged coaxially along a transmission shaft (16) that is rotatable about the rotation axis (R), and the transmission shaft is preferably formed as a hollow shaft.

10. The pump according to any one of claims 1-9, wherein, The secondary insulation layer (28) completely encloses the stator core (21, 22, 23) and the coil (25) to the tooth tip (23), such that only the tooth tip (23) of the stator core (21, 22, 23) is not covered by the secondary insulation layer (28) at least at the sliding surface (24) that defines the operating gap (14).

11. The pump according to any one of claims 1-10, wherein, The secondary insulation layer (28) and the motor housing (6) surrounding the stator core (21, 22, 23) and / or the assembly geometry (6c) for mounting the pump and / or the wiring housing (7) for connecting to an external system to power and / or control the drive motor (10, 20) and / or the rotary bearing structure (8) for radially supporting the drive shaft (16) which is non-rotatably connected to the rotor (10) and / or the impeller (15) are integrally formed by a one-time molding process, for example as a plastic casting.

12. The pump according to any one of claims 1-11, wherein, The secondary insulation layer (28) forms a wiring housing (7) for one or more electrical connection elements (42, 46), and the stator (20) can be connected to an external power supply system and / or controller, for example by plug-in connection, through the wiring housing (7) and the corresponding electrical connection elements (42, 46).

13. The pump according to claim 11 or 12, wherein, The corresponding electrical connection elements (42, 46) are embedded in the secondary insulation layer (28) and are thereby positioned and fixed relative to the motor housing (6) and / or the wiring housing (7).

14. The pump according to any one of claims 1 - 13, comprising a rotary bearing structure (8) for rotatably mounting the rotor (10), wherein the secondary insulation layer (28) and the rotary bearing structure (8) are integrally formed by one - shot molding, for example as a plastic injection molding.

15. The pump according to any one of claims 1-14, wherein, The operating clearance (14) has a radial operating clearance width w, which is measured radially with respect to the rotational axis (R) between the sliding surface (24) of one of the stator teeth (23) and the circumference of the rotor (10) opposite across the operating clearance (14), and the primary insulation layer (26) has a thickness D in the region of the tooth tip (23), where w < D or w < 0.5×D.

16. The pump according to any one of claims 1 - 15, wherein the primary insulation layer (26) and the secondary insulation layer (28) radially retract in the tooth gap region behind the sliding surface (24) of the stator teeth (23); or conversely the primary insulation layer (26) and the secondary insulation layer (28) are flush - butt - jointed with the sliding surface (24) of the stator teeth (23) in the tooth gap region.

17. The pump according to any one of claims 1 - 16, the pump being used as a cooling medium pump for transporting a water / ethylene glycol mixture and / or a dielectric heat - conducting oil to perform cooling or temperature control of the following objects, the temperature control including cooling and / or heating: an internal combustion engine and / or transmission components of a fuel - driven vehicle transmission system and / or components of a battery - driven electric vehicle transmission system and / or battery cells of a motor vehicle traction battery.

18. A method of manufacturing a stator for an electric drive motor (10, 20), preferably the stator (20) of the drive motor (10, 20) of the pump according to any one of claims 1 - 17, comprising the following steps: a. Molding an electrically insulating first plastic around a stator core (21, 22, 23), the stator core including stator teeth (21) and tooth gaps, the stator teeth being at least substantially radially directed with respect to the motor axis (R) and having exposed tooth tips (23), the tooth gaps remaining between the stator teeth (21) to form a primary insulation layer (26) that surrounds the stator teeth (21) and preferably lines the tooth gaps; b. Winding the stator teeth (21) with the primary insulation layer (26) with electric wire to form an electric coil (25); c. Injecting - molding an electrically insulating second plastic layer around the stator core (21, 22, 23) and the coil (25) to form a secondary insulation layer (28), the secondary insulation layer (28) wrapping the coil (25) and the stator core (21, 22, 23) and extending to cover the coil (25) up to the tooth tips (23); d. When spraying the secondary insulation layer (28), forming cooling channels (29) axially penetrating the secondary insulation layer (28) in the tooth gap region for guiding the fluid that cools the stator; Wherein, at the tooth tip (23), the sliding surface (24) is used to form an operating gap (14) with the rotor (10) of the drive motor (10, 20), and the sliding surface is not covered by the primary insulation layer (26) and the secondary insulation layer (28).

19. The method according to claim 18, wherein, The primary insulating layer (26) and the secondary insulating layer (28) are injection molded in such a manner that the sliding surface (24) remains uncontaminated with the first plastic and the second plastic during the injection molding process, or the plastic attached to the sliding surface (24) is removed after injection molding, preferably by cutting.

20. The method according to claim 18 or 19, wherein, The primary insulation layer (26) in the area of ​​the tooth tip (23) is injection molded in the form of one or more bosses and / or grooves by one or more engagement geometries (27; 27a) surrounding each of the stator teeth (21), and each engagement geometry (27; 27a) contacts and melts or welds with the second plastic when the secondary insulation layer (28) is sprayed, so that the corresponding engagement geometry (27; 27a) is embedded in the secondary insulation layer (28) in the fused state, or forms a micro-mixed structure with the first plastic in the fused state.

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