Device for driving a compressor and method for manufacturing the device

Abstract

This invention relates to an apparatus for driving a compressor, particularly an electric motor, and a method for manufacturing the apparatus, the apparatus having a rotor and a stator (1) with a stator core (2), the rotor and stator being arranged along a longitudinal axis (7). The stator (1) has: connecting cables (8a) and connecting conduits (8b) arranged on a first end face of the stator (1), the connecting cables being formed as multiple segments of conductors (8) of coils (5); an insulating element (6), the wall of the insulating element being formed in a substantially hollow cylindrical shape and protruding axially beyond the stator core (2) on the first end face of the stator (1); and a cover element (3) having mounting elements (4) having connecting channels for mounting insert connectors (9), each connecting channel being completely enclosed by a wall (4a). The connecting cables (8a) or connecting conduits (8b) are arranged circumferentially on the wall of the insulating element (6). The cover element (3) contacts the first end face of the stator (1) on the stator core (2) in the axial direction and covers the protrusion of the insulating element (6) beyond the wall of the stator core (2). The volume enclosed by the stator core (2), the cover element (3) and the protrusion of the insulating element (6) beyond the wall of the stator core (2) is at least regionally filled with potting compound (12).

Description

Technical Field

[0001] This invention relates to a device for driving a compressor, particularly an electric motor, for compressing a gaseous fluid, specifically a coolant. The compressor can be used in the refrigerant circuit of a motor vehicle's air conditioning system. The device has a rotor and a stator extending along a common longitudinal axis. The stator has connecting cables and connecting lines of multiple sections formed as coil wires. Background Technology

[0002] Compressors known from existing technology for mobile applications—particularly those used in motor vehicle air conditioning systems and for delivering refrigerant through a refrigerant circuit, also known as refrigerant compressors—are typically configured as either reciprocating or scroll compressors with variable displacement. The compressors are driven by pulleys or electrically.

[0003] In addition to an electric motor for driving the appropriate compression mechanism, an electric compressor also has an inverter for driving the electric motor. The inverter is used to convert the direct current from the vehicle battery into alternating current supplied to the electric motor via electrical connections.

[0004] The conventional electric motor of an electrically driven compressor is formed with an annular stator core and a rotor, on which coils are arranged, with the rotor located inside the stator core. The rotor and stator are aligned on a common axis of symmetry or the rotor's axis of rotation and are enclosed by a housing. In order to reduce the installation space inside the power vehicle and to secure the stator in the housing, the clearance between the components of the electric motor, especially the clearance between the stator and the housing, is very narrow.

[0005] The inverter has plug-in connectors for electrical connection to the electric motor. These connectors are formed as separate components and pins and are electrically connected to the connecting lines of the stator coils. The connecting cables are routed along the end faces of the stator core and, in most cases, are not covered by the stator insulation that abuts against the electric motor housing. Furthermore, the gap between the components and the housing is typically very narrow.

[0006] To provide electrical connections and high insulation resistance, such as between connecting lines of conductors, the connecting lines or wires of the phase conductors are electrically insulated from each other and from other conductive parts of the stator and motor housing. The areas of the connecting lines of the individual phases of an electric motor, as sections of the coil conductors, can be plastically insulated, with the conductors specifically made of enameled copper wire.

[0007] Furthermore, depending on the voltage level, sufficient insulation gaps may be required between conductive components, for example, to avoid short circuits caused by insufficient creepage distance and gaps. Insulators may also have defects or voids, particularly pinholes, that are generated during the manufacturing process and substantially reduce insulation resistance, thus posing a risk of electric flashover, particularly to components of the housing. The risk of electric flashover between copper wires is very high if two copper wires with defects in the insulation are arranged side-by-side, and these defects are positioned directly opposite or at least close to each other.

[0008] In particular, the requirements for electrically driven compressors are very high, especially when operating them at high voltages, such as up to 1,000V. For example, international standards require creepage distances and clearances between two conductors or between conductors and adjacent conductive parts to be at least 10mm to 14mm for a specific voltage range. The insulation system for hermetically sealed electric motors used at at least 800V (UHV) is one of the biggest challenges in automotive engineering. Hermetically sealed electric motors are used in air conditioning systems, which are installed inside highly modernized electric motors operating at approximately 400V (EHV). In highly modernized electric motors, the shortest air gap between two coils is typically about 4mm and the shortest creepage distance is typically about 5mm.

[0009] To achieve the required insulation gap or distance, electric motors in existing electrically driven compressors require either a sufficiently large distance between the connecting conduit and other conductive parts of the compressor, or, where the connecting conduit has insufficient distance from other conductive parts, a completely enclosed area. Compared to unenclosed connecting conduits, enclosed connecting conduits allow for narrower gaps between the connecting conduits and other conductive parts of the compressor, depending on the voltage level. When using motors with unenclosed connecting conduits, the motor requires a large installation space, and this large installation space also necessitates considerations for electrically driven compressors. Summary of the Invention

[0010] Technical issues

[0011] The objective of this invention is to provide and improve an apparatus, particularly an electric motor, for driving an electrically driven compressor that drives a gaseous fluid. The apparatus is designed to meet insulation compliance requirements for voltage levels of at least 800V to 1000V, wherein, in particular, the wires or connecting cables or conduits must be electrically insulated from each other and from adjacent conductive components. The apparatus must be designed to be easily and therefore time-efficiently assembled, and it will have as few individual components as possible and be easily constructed to minimize, for example, weight, required space, and manufacturing costs.

[0012] Solution

[0013] The objective of this invention is achieved through an object having the features of the independent patent claims. Other embodiments are described in detail in the dependent patent claims.

[0014] The objective of this invention is achieved by means of a device for driving a compressor of a gaseous fluid, specifically an electric motor, according to the invention. The device has a rotor and a fixed stator with a stator core, the rotor and the fixed stator extending between two end faces along a common longitudinal axis.

[0015] The stator has connecting cables and connecting pipes that are formed as coil conductors, the connecting cables and connecting pipes are arranged on the first end face of the stator, and the stator is preferably positioned in the radial direction on the outer surface of the rotor, thereby enclosing the rotor.

[0016] The conductors in the coil region are preferably made of enameled and wound copper wire, wherein the unwound ends of the conductors extend from the corresponding windings as connecting cables or connecting conduits and each serves as a magnetically inert section of the conductor. The connecting cables—for example, for connectors and for connecting coils of the same phase—are preferably formed in the coil region as enameled only, similar to the conductors in the coil region, while the connecting conduits—for example, for electrical connections to connectors of electric motors—are preferably insulated with a plastic sheath.

[0017] The stator has an insulating element whose wall, which is basically hollow cylindrical in shape, particularly hollow circular cylindrical in shape, protrudes beyond the stator core in the axial direction on the first end face of the stator, wherein connecting cables or connecting pipes are arranged on the wall of the insulating element in the circumferential direction.

[0018] In this context, the term "axial direction" should be understood as the direction of the longitudinal axis of the stator, which also corresponds to the longitudinal axis and rotation axis of the rotor. The end faces aligned in the axial direction are arranged on a plane perpendicular to the longitudinal axis.

[0019] Furthermore, according to the invention, the stator has a cover element with mounting elements having connection channels, each connection channel being surrounded by a wall around its periphery, the connection channels being intended for mounting a plug-in connector. The cover element is located on a first end face of the stator, thereby covering the wall of the insulating element protruding beyond the stator core and the connecting cable or connecting conduit, the cover element being arranged such that it contacts the stator core and completely encloses the stator core around its periphery.

[0020] According to the concept of the present invention, the volume of the stator core, cover element and insulating element protruding beyond the wall enclosure of the stator core is at least regionally filled with potting compound.

[0021] The insulating element is preferably arranged radially such that it contacts the interior of the outer wall of the stator core. The insulating element can then be securely connected to the stator core.

[0022] According to another embodiment of the invention, the twisted section of the conductor wound to form a coil—which is aligned in the direction of the first end face of the stator—is at least regionally shielded by a cover element and encapsulated using a potting compound.

[0023] According to an advantageous embodiment of the invention, the cover element is in the form of a hollow cylindrical tube aligned in the axial direction and is formed as a ring, which preferably has a fully closed periphery and has two axially aligned ring surfaces and one radially aligned ring surface.

[0024] The axially aligned annular surfaces—preferably arranged on the outer and inner radii of the cover element—are aligned parallel to each other and connected to each other via radial annular surfaces. Another advantage of the invention is that the radially aligned annular surfaces are arranged on a plane aligned perpendicular to the longitudinal axis of the stator, and the axially aligned annular surfaces are arranged to be connected to each other with their end faces, such that the cover element has a U-shape in the cross-section through the annular profile.

[0025] At least one end face of an axially aligned annular surface, particularly an end face of an annular surface arranged on the inner radius of the cover element, contacts the stator core. This end face is located distal to and aligned with the radially aligned annular surface. The volume formed between the interconnected annular surfaces can be used to contain potting compound. The annular surfaces are preferably formed to be closed around the entire periphery, wherein only the radial annular surfaces have through openings in the region of the wall of the connecting channel.

[0026] The cover element is preferably made of an electrically insulating material. Therefore, the cover element arranged on the stator core, also in conjunction with a potting compound, is specifically designed to ensure the required insulation clearance.

[0027] Another advantage of the invention is that the mounting element for the plug-in connector is an integral part of the cover element, so that the cover element and the mounting element are formed as a unit, particularly a single-piece injection molded element.

[0028] According to a preferred embodiment of the invention, the connecting cable or connecting conduit of the conductor is arranged such that the connecting cable or connecting conduit contacts the outer surface of the wall of the insulating element and is substantially aligned along the circumferential direction of the wall. The outer portion of the wall of the insulating element preferably has at least one collar, which is formed circumferentially as a recess, particularly a groove, and is intended for mounting a connecting cable or a connecting conduit. The connecting cable or connecting conduit of the conductor can be fully engaged in the collar.

[0029] "Fully coupled" should be understood as the conductor's connecting cable or conduit being arranged in a collar, wherein the conductor is embedded in the collar with its entire diameter. The conductor will not protrude beyond the collar at any position. The maximum diameter of the conductor is less than or corresponds to the depth of the collar.

[0030] At least one collar inside the wall of the insulating element is preferably arranged on a plane aligned perpendicular to the longitudinal axis of the stator. When at least two collars are arranged inside the wall of the insulating element, the collars are preferably arranged on a plane aligned perpendicular to the longitudinal axis of the stator and spaced appropriately apart from each other.

[0031] According to another embodiment of the invention, the insert connector is made of a conductive material, is cylindrical, particularly circular or pin-shaped, and is carried through a connection channel enclosed by a wall of a mounting element of a cover element, wherein preferably a groove is provided between the wall of the mounting element and the insert connector, the groove being formed in a hollow cylindrical shape and intended for mounting a contact element and for containing a potting compound.

[0032] According to another preferred embodiment of the invention, each contact element is formed as a hollow cylindrical sleeve for mounting a plug-in connector. The contact elements are arranged such that the contact elements preferably enclose the plug-in connector with the inner surface of their lateral surfaces and establish electrical contact.

[0033] Another advantage of the invention is that the outer diameter of the contact element substantially corresponds to the inner diameter of the wall of the connecting channel plus a groove formed over the entire periphery and designed to accommodate a potting compound, such that the potting compound can be arranged between the walls of the contact element and the mounting element to enable the contact element to be connected to the mounting element and thus to the cover element.

[0034] According to another advantageous embodiment of the invention, the connecting conduit of the coil wire is in conductive contact at one end of the contact element with an insert connector disposed inside the contact element, wherein the end of the wire is in conductive contact with the contact element, preferably on the end face of the contact element facing the stator alignment.

[0035] The object of the present invention is also achieved by a method according to the invention for manufacturing the device, particularly an electric motor, or a compressor for driving a gaseous fluid. The method comprises the following steps followed during stator assembly:

[0036] - The stator core is arranged to have insulating elements and wires, the wires being wound to form coils and having connecting cables and connecting conduits, wherein the connecting cables and connecting conduits are arranged on the wall of the insulating element, which protrudes beyond the stator core in the axial direction.

[0037] - Cover elements with mounting elements are arranged on the axially aligned end faces of the stator core. Each mounting element is formed with a connection channel, which is completely enclosed by a wall. Each connection channel is formed with a contact element, each contact element being electrically connected to a connecting line of a conductor. A plug-in connector is inserted into each contact element.

[0038] - Use a potting compound to at least regionally fill the following volumes: namely, the volumes formed between the stator core, cover elements, and insulating elements, and the volumes formed between the walls of the mounting elements and the contact elements, and

[0039] - The rotor and stator are arranged on a common longitudinal axis, wherein the stator encloses the rotor in the radial direction.

[0040] Furthermore, a particular advantage of the present invention is that the volume formed as a coherent, consistent hollow space facilitates the filling of the potting compound in a single process step.

[0041] According to another embodiment of the invention, during the filling process, a potting compound is used to at least regionally fill the volume enclosed by the cover element and the twisted sections of the conductors, which are wound to form coils and aligned in the direction of the stator end face. The volume formed between the stator core, the cover element and the insulating element, the volume formed between the wall of the mounting element and the contact element, and the volume enclosed by the cover element and the twisted sections of the conductors are formed as a coherent unit, which is wound to form coils and aligned in the direction of the stator end face.

[0042] Advantageous embodiments of the present invention allow for devices for driving compressors for compressing gaseous fluids, particularly electric motors, and compressors for refrigerants in the refrigerant circuit of a motor vehicle air conditioning system.

[0043] Advantages of the present invention

[0044] The apparatus for driving a compressor for a gaseous fluid according to the invention—which requires a minimum number of components—and the method for manufacturing the apparatus, in general, have several further advantages:

[0045] - The ease of assembling the cover element on the insulating element or stator core, and the ease of fixing the cover element, and the maximum possible electrical insulation of the connecting cables and connecting lines, especially by means of filling the U-shaped cross-section of the cover element with a potting compound, wherein, in one process step, the connecting cables, connecting lines, especially the connecting lines connected to the connectors on the contact elements, and all other conductive connectors arranged inside the volume enclosed by the cover element and the stator core are insulated from each other and hermetically isolated from the external environment; in addition, the current-carrying connectors are completely isolated from the refrigerant, and thus the degree of contamination inside the encapsulation area is minimized;

[0046] - Depending on the voltage level, increase the insulation resistance and reduce the footprint, including insulation of the electrical insertion connection between the insertion connector and the contact element;

[0047] - By providing the required insulation distance—which depends on the voltage level—short-circuit currents are avoided between the conductors and other conductive, passive components;

[0048] - Reduce manufacturing waste caused by insufficient insulation resistance, thereby minimizing costs, and

[0049] - Maximize the lifespan of the compressor.

[0050] When assembling the cover components in a single step, the magnetically inert connections between coils or wires, especially the connecting conduits of wires, and particularly the magnetically inert connections of connecting cables, are completely covered to expand the insulation gap and thus increase the insulation resistance. Furthermore, the end face of the stator aligned with the motor housing is mechanically reinforced, which positively influences the stator's contraction process within the housing. Attached Figure Description

[0051] Further details, features, and advantages of embodiments of the present invention will become apparent from the following description of examples of embodiments with reference to the accompanying drawings. The views illustrate the following:

[0052] Figure 1aThe stator of an electric motor is shown in a perspective view. The electric motor is a device for driving a compressor for a gaseous fluid. The stator is provided with a stator core and a cover element. The cover element is arranged on the first end face of the stator and has a mounting element for mounting a plug-in connector.

[0053] Figure 1b and Figure 1c : Detailed views of the first end face of the stator without the cover element are shown in perspective.

[0054] Figure 1d The cross-sectional view shows the case with the cover element. Figure 1a Detailed view of the stator in the middle;

[0055] Figure 2a and Figure 2b Each of the cover elements is shown in top view, which is shown as having a plug-in connector that inserts into the mounting element—shown in detail—and additional connecting lines;

[0056] Figure 2c The cover element is shown in cross-section through the mounting element, which is used for insertion of the plug-in connector. Detailed Implementation

[0057] Figure 1a The stator 1 of an electric motor is shown in a perspective view. The electric motor serves as a device for driving a compressor of gaseous fluid to deliver refrigerant via a refrigerant circuit, the compressor being specifically designed for use in the air conditioning systems of motor vehicles. The stator 1 is shown in a perspective view as having a stator core 2 and a cover element 3 disposed on a first end face of the stator 1 and fitted with a mounting element 4 for mounting a plug-in connector. Figure 1b and Figure 1c These are detailed views of the first end face of the stator 1, shown in perspective, with coils 5 arranged on the stator core 2 but without a cover element. Figure 1d The cross-sectional view shows the case with cover element 3. Figure 1a Detailed view of stator 1 in the image.

[0058] An electric motor, such as a three-phase AC motor, has a rotor and a stator core 2, the rotor not shown, which is arranged radially on the outer surface of the rotor and thus surrounds the rotor. The stator core 2 and the insulating element 6 extend along a longitudinal axis 7 from a first end face of the stator 1 to a second end face, the longitudinal axis 7 also corresponding to the longitudinal axis of the stator 1 and the axis of rotation of the rotor. The stator core 2 is preferably formed as a stack of sheets, and the insulating element 6 is made of an electrically insulating material. The insulating element 6 is preferably formed as a molded overlay of the stator core 2 and is therefore a single-piece component.

[0059] Each coil 5 is composed of a single wire, also referred to as a conductor 8, which is formed as an electrical conductor and wound around a radially inwardly extending region of the stator core 2. All conductors 8 are made of enameled copper wire. The unwound ends of the conductors 8 are led out from the corresponding windings to serve as connecting cables 8a or connecting conduits 8b, each of which is a magnetically inactive section.

[0060] The connecting cable 8a—which is used to connect coils 5 of the same phase to each other—is formed as a first section of conductor 8 specifically as enameled wire, while the connecting conduit 8b—which is constructed as a connector for electrical connection to an electric motor and serves as a second section of conductor 8—is preferably insulated by a plastic material.

[0061] The radially inwardly extending region of the stator core 2 is in the form of a web and is evenly distributed around the periphery of the outer wall of the stator core 2. An insulating element 6—which electrically insulates the stator core 2 from the conductor 8 of the coil 5—is arranged between the conductor 8 of the coil 5 and the corresponding region of the stator core 2. The insulating element 6 is formed as an axially extending element located at the inwardly aligned end of the web. The torsional section of the insulating element 6, protruding in the manner described above, is used to fix the conductor 8 of the coil 5, which is wound around the web of the stator core 2.

[0062] The stator core 2, coil 5, and insulating element 6 form the stator unit of the electric motor.

[0063] The insulating element 6—which is preferably formed as a molded overlay of the stator core 2—contacts the interior of the outer wall of the stator core 2 in the radial direction with its outer surface facing outward. The wall of the insulating element 6 protrudes beyond the stator core 2 in the axial direction from the end face of the stator 1, as particularly in… Figure 1b and Figure 1c As shown in the diagram, the magnetoactive section of the conductor 8—which is wound to form a coil—is arranged around a region of the insulating element 6 extending radially inward, wherein the insulating element 6 is arranged between the stator core 2 and the conductor 8 of the coil 5.

[0064] The region of the insulating element 6 protruding beyond the stator core 2 has a wall extending radially, which is formed as a substantially hollow cylinder and broken circumferentially. These sections of the conductor 8—which are magnetically inert, not wound to form coils, and routed between the windings of the coil 5 as connecting cables 8a—are arranged such that they extend around the entire periphery of the region of the insulating element 6 protruding beyond the stator core 2, and these sections are incorporated into a collar formed as a groove. Additionally, magnetically inert sections of the conductor 8 forming connecting conduits 8b can also be arranged inside this collar, which is also referred to as the mounting area. The region of the insulating element 6 protruding beyond the stator core 2 on the first end face of the stator 1, together with the magnetically inert sections of the conductor 8, is also referred to as the connecting ring.

[0065] Depending on the motor's voltage level, the relevant clearances, also known as insulation distances, between the motor's conductor 8 and other conductive, metallic components such as the housing or compressor parts must be observed according to relevant standards to prevent, for example, short circuits or flashovers between the conductor 8 and adjacent conductive parts. Compared to the insulation gap without the cover element, the insulation gap is extended due to the installation of the cover element 3, thereby reducing the risk of short circuits or flashovers.

[0066] A cover element 3 with mounting element 4 is arranged on the first end face of the stator 1, thereby covering the wall of the insulating element 6 that protrudes beyond the stator core 2 in the axial direction. The mounting element 4 has a connection channel completely enclosed by the wall 4a and designed for mounting a plug-in connector, such as... Figure 1d As shown in the image.

[0067] With the stator 1 assembled, the cover element 3—formed as a ring around the longitudinal axis 7—is in full contact with the stator 1, and particularly with the stator core 2, in the axial direction, wherein the outer diameter of the cover element 3 is smaller than the outer diameter of the stator core 2. The mounting element 4 for the insertion connector 9 is an integral part of the cover element 3, such that the cover element 3 and the mounting element 4 are formed as a single unit, specifically a one-piece injection molded element. This one-piece form is achieved during the molding process.

[0068] The cover element 3—formed as an axially aligned ring closed around its entire circumference and generally cylindrical, particularly hollow cylindrical, specifically hollow circular cylindrical—has two axially aligned annular surfaces 3a and one radially aligned annular surface 3b. The axial annular surfaces 3a—formed on the outer and inner radii of the cover element 3—are aligned parallel to each other and connected to each other via the radial annular surfaces 3b. The radial annular surfaces 3b—arranged on planes aligned perpendicular to the longitudinal axis 7—connect the axial annular surfaces 3a to each other, such that the cover element 3 has a U-shape in cross-section through the annular profile, the U-shape preferably having similar leg lengths. The first axial annular surface 3a of the axial annular surfaces 3a is formed as the outer wall, while the second axial annular surface 3a of the axial annular surfaces 3a is formed as the inner wall. The radial annular surfaces 3b connect the axial annular surfaces 3a to each other on their end faces. The annular surfaces 3a and 3b are each formed as surfaces that are closed around the entire circumference, wherein the radial annular surface 3b is interrupted only in the region of the wall 4a of the connecting channel so that the insert connector 9 can be installed.

[0069] The volume formed between the ring surfaces 3a and 3b is used to accommodate the region of the insulating element 6 protruding beyond the stator core 2, as well as the connecting cable 8a and connecting conduit 8b of the conductor 8 arranged in this region, and thus the volume is used to accommodate the connecting ring and as a molded part for accommodating the potting compound, wherein the cover element 3—which is formed in a basically hollow cylindrical shape—is arranged such that the inner surface of the first axial ring surface 3a, which forms the outer wall, and the outer surface of the second axial ring surface 3a, which forms the inner wall, are each oriented along the lateral surface of the wall of the region of the insulating element 6 protruding beyond the stator core 2.

[0070] Specifically, the section of the enameled connecting cable 8a of the conductor 8, which is covered by the cover element 3 facing the environment of the stator 1—this section is not wound to form a coil and is led out from or introduced into the corresponding winding—and the connecting conduit 8b, and the twisted section of the conductor 8, which is wound to form a coil 5 and aligned with the first end face of the stator 1. Specifically, the connecting cable 8a and the connecting conduit 8b of the conductor 8 are arranged radially such that the connecting cable 8a and the connecting conduit 8b are protected between the insulating element 6 and the cover element 3. Since both the cover element 3 and the insulating element 6 are electrically insulating components, the conductor 8 formed in the insulating element 6 and covered by the cover element 3 is completely enclosed by the electrically insulating portion.

[0071] The cover element 3 is designed to provide an insulating gap or required insulation resistance between itself and other conductive components, such as the motor housing, particularly by, for example, an extended creepage distance between itself and the motor housing—which depends on the voltage level.

[0072] The following volume, which forms a hollow space, is at least regionally filled or stuffed with potting compound: namely, the volume enclosed by the annular surfaces 3a, 3b and connecting ring of the cover element 3 and by the twisted section of the conductor 8—which is wound to form the coil 5 and aligned in the direction of the first end face of the stator 1—so that the insulating element 6 and the cover element 3 are securely and inseparably connected to the conductor 8 arranged between the insulating element 6 and the cover element 3.

[0073] When the volume or hollow space is filled with a potting compound as an additional adhesive, so-called cemented connections are formed so that any gap closure for current flow and thus possible flow path closure for leakage current or creepage current can be used. In this case, the cover element 3, the insulating element 6, and the connecting cables 8a and connecting conduits 8b arranged on the insulating element 6 are connected to each other and cemented together in particular to avoid creepage distance between adjacent parts and to extend the creepage distance between conductive elements to the required minimum.

[0074] Therefore, adhesive bonding is understood as joining two materials together by means of a suitable adhesive, such as glue, resin, epoxy resin, or other filling material that prevents the flow of current between two conductive parts.

[0075] The cover element 3, therefore, serves not only to protect the connecting ring but also as a molding element for the potting compound, which separates the conductors 8 of different phases from each other. Since the conductors 8 are arranged with very narrow gaps between each other, the required creepage distances and clearances are ensured by filling the entire hollow space between the wall of the insulating element 6 protruding beyond the stator core 2 and the cover element 3 with the potting compound—so that the conductors 8 are embedded in the potting compound. Thus, for example, an insulation system is provided that meets the requirements for applications with ultra-high voltages of at least 800V.

[0076] Furthermore, by covering the insulating element 6 with the cover element 3 and the potting compound—which protrudes beyond the stator core 2 on the end face of the stator 1 and is provided with a completely airtight seal for the conductors 8—arranged on the connecting ring—the refrigerant, as a fluid, is prevented from flowing inside the housing of the electric motor and between the conductors 8.

[0077] After the electric motor or compressor is installed, and especially during operation, the self-disassembly of the connection between the cover element 3 and the insulating element 6 is excluded. The cover element 3 and the insulating element 6 are connected as securely as possible, especially during operation, and these components will not separate without force, such as being disassembled due to vibration.

[0078] Figure 2aand Figure 2b Each is shown in top view as a cover element 3, which is shown as having a plug-in connector 9 that inserts into the mounting element 4—shown in detail—and a connecting conduit 8b, while Figure 2c The cover element 3 is shown in cross-section through the mounting element 4 into which the plug-in connector 9 is inserted. The conductor 8 of each phase is connected to the inverter via the plug-in connector 9—which serves as the electrical connection element between the stator 1 and the inverter.

[0079] A pin-shaped insert connector 9, made of conductive material, is inserted into a connection channel passing through the cover element 3 and the mounting element 4. The connection channel is enclosed by a wall 4a and serves as a component for the electrical connection between the coil 5 of the electric motor and the inverter. A ring-shaped or hollow cylindrical groove 10 is formed between the wall 4a of the mounting element 4 and the insert connector 9, which is particularly... Figure 2a As shown in the figure, the groove 10 is used to mount the contact element 11, which is formed in the form of a sleeve, and to contain the potting compound 12.

[0080] The connecting conduit 8b of the wire 8 of coil 5 is electrically connected at the end 8c of the wire 8 to the insert connector 9 arranged inside the mounting element 4 or the contact element 11 via the contact element 11. The end 8c of the wire 8 contacts the contact element 11 mechanically and electrically on the first end face of the contact element 11 aligned with the stator 1. The second end face of the contact element 11 is aligned in a direction away from the stator 1 and towards the inverter (not shown here).

[0081] The contact element 11—which is also formed in the shape of a hollow cylindrical tube—is arranged such that the contact element 11 encloses the insert connector 9 with an inner surface of its lateral surface in a manner that provides full-area electrical contact. The inner diameter of the inner surface of the contact element 11 is substantially corresponding to or slightly smaller than the outer diameter of the hollow cylindrical insert connector 9, so as to facilitate a press fit between the insert connector 9 and the contact element 11.

[0082] Contact element 11 is arranged inside the connection channel of mounting element 4, wherein the outer diameter of contact element 11 substantially corresponds to the inner diameter of the wall 4a of the connection channel plus the groove 10 for receiving potting compound 12. Therefore, potting compound 12 is arranged between contact element 11 and wall 4a of mounting element 4 so that contact element 11 can be connected to mounting element 4 and thus to cover element 3.

[0083] When the stator 1 is assembled, and after the various components, such as the stator core 2—which has an insulating element 6 and wires 8 each having connecting cables 8a and connecting conduits 8b, cover element 3, contact element 11, and plug-in connector 9, are arranged, the hollow space formed between the cover element 3 and the insulating element 6, and the hollow space formed between the wall 4a and the contact element 11, are filled or plugged with potting compound 12. Since the aforementioned hollow space forms a coherent volume, filling with potting compound 12 can be performed as a single process step, wherein the potting compound 12 fills or occludes the following volumes: namely, the volume enclosed by the annular surfaces 3a, 3b of the cover element 3 and the connecting ring, and the volume enclosed by the twisted section of the wire 8 wound to form the coil 5 and the wall 4a of the mounting element 4 and the contact element 11, such that the cover element 3 is securely and inseparably connected to the insulating element 6 and the wire 8 arranged between the cover element 3 and the insulating element 6, and is securely and inseparably connected to the contact element 11 or the plug connector 9.

[0084] The connecting cables 8a and 8b of the conductor 8, along with the plug connector 9 and the contact element 11, are completely encapsulated or covered by the potting compound 12 and are therefore electrically insulated from each other and from adjacent conductive parts.

[0085] Alternatively, filling with a potting compound can be performed in separate process steps, wherein after the insertion connector 9 is assembled into the mounting element 4 inside the already filled cover element 3, and the contact element 11 is specifically arranged in the mounting element 4, the hollow space formed between the contact element 11 and the wall 4a of the mounting element 4 is filled, thereby insulating the insertion connectors 9 from each other.

[0086] The volume was filled with potting compound 12 to a height of up to Figure 2c The specific levels indicated by dashed lines ensure that all areas crucial for creepage current are filled. With this volume filled, adjacent components, especially conductive components, are insulated from each other, thus preventing the formation of creepage distances—also known as potential paths—that allow creepage current or short-circuit current to form. This interrupts the flow path or path for potential creepage current and minimizes the extension of the stator 1 with the stator core 2, insulating element 6, and conductor 8, particularly in the direction of the longitudinal axis 7. By separating current-carrying components from each other and from other conductive components, the requirements for insulation within the specified voltage range are fully met.

[0087] Industrial applications

[0088] This invention relates to a device for driving a compressor, particularly an electric motor, for compressing a gaseous fluid, specifically a refrigerant. The compressor can be used in the refrigerant circuit of a motor vehicle's air conditioning system. The device has a rotor and a stator extending along a common longitudinal axis. The stator has connecting cables and connecting lines of multiple sections formed as coil wires.

Claims

1. An apparatus for driving a compressor for a gaseous fluid, the apparatus having a rotor and a stator (1) with a stator core (2), the rotor and the stator (1) extending between two end faces along a common longitudinal axis (7), wherein, The stator (1): -Having connecting cables (8a) and connecting conduits (8b), the connecting cables (8a) and the connecting conduits (8b) are formed as multiple sections of conductors (8) of coils (5) arranged on the first end face of the stator (1); -Having an insulating element (6), the insulating element (6) protrudes axially beyond the stator core (2) in a wall of a substantially hollow cylindrical shape on the first end face of the stator (1), wherein the connecting cable (8a) and / or the connecting conduit (8b) are arranged circumferentially around the wall of the insulating element (6); - It has a cover element (3) provided with mounting elements (4), each mounting element (4) having a connection channel for mounting a plug-in connector (9), each of the connection channels being enclosed by a wall (4a) around its periphery, the cover element (3) being arranged to contact the entire area of ​​the stator core (2) in the axial direction around the periphery of the stator core (2) on the first end face of the stator (1), such that the cover element (3) covers the protrusion of the insulating element (6) beyond the wall of the stator core (2) and the connecting cable (8a) and / or the connecting conduit (8b), The volume of the wall enclosure formed by the protrusions of the stator core (2), the cover element (3), and the insulating element (6) beyond the stator core (2) is at least regionally filled with potting compound (12).

2. The apparatus according to claim 1, characterized in that, The twisted portion of the conductor (8) is at least regionally covered by the cover element (3) and encapsulated in the potting compound (12), and the twisted portion of the conductor (8) is wound to form the coil (5) aligned in the direction of the first end face of the stator (1).

3. The apparatus according to claim 1, characterized in that, The cover element (3) has the form of a hollow cylindrical tube aligned in the axial direction.

4. The apparatus according to claim 1, characterized in that, The cover element (3) is formed as a ring, which is closed around its periphery, and the ring has two axially aligned ring surfaces (3a) and one radially aligned ring surface (3b).

5. The apparatus according to claim 4, characterized in that, The axially aligned annular surfaces (3a) are arranged on the outer and inner radii of the cover element (3), and the axially aligned annular surfaces (3a) are aligned parallel to each other and connected to each other via the radial annular surfaces (3b).

6. The apparatus according to claim 4, characterized in that, The radially aligned annular surfaces (3b) are arranged on a plane perpendicular to the longitudinal axis (7), and the axially aligned annular surfaces (3a) are each arranged on an end face and connected to each other on the end face, such that the cover element (3) has a U-shape in the cross section through the annular profile.

7. The apparatus according to claim 6, characterized in that, The cover element (3) is arranged to contact the stator core (2) through one end face of at least one axially aligned annular surface (3a), the end face being located distal to the end face connected to the radially aligned annular surface (3b) and aligned with the end face connected to the radially aligned annular surface (3b).

8. The apparatus according to claim 4, characterized in that, The annular surfaces (3a, 3b) are formed such that the annular surfaces (3a, 3b) are closed over their entire circumference, wherein the radial annular surface (3b) has a through opening in the region of the wall (4a) of the connecting channel.

9. The apparatus according to claim 1, characterized in that, The cover element (3) is made of an electrically insulating material.

10. The apparatus according to claim 1, characterized in that, The connecting cable (8a) and / or the connecting conduit (8b) of the conductor (8) are arranged such that the connecting cable (8a) and / or the connecting conduit (8b) are in contact with the outer surface of the wall of the insulating element (6).

11. The apparatus according to claim 1, characterized in that, The wall of the insulating element (6) has at least one collar for mounting a connecting cable (8a) and / or a connecting conduit (8b), the at least one collar extending fully along the circumferential direction and formed as a recess.

12. The apparatus according to claim 1, characterized in that, The insert connector (9) is made of conductive material and has a cylindrical shape, and is arranged such that the insert connector (9) passes through the connection channel enclosed by the wall (4a) of the mounting element (4) of the cover element (3).

13. The apparatus according to claim 12, characterized in that, A hollow cylindrical groove (10) is formed between the wall (4a) of the mounting element (4) and the insert connector (9), the groove (10) being used to mount the contact element (11) and to contain the potting compound (12).

14. The apparatus according to claim 1, characterized in that, Each plug connector has a contact element (11) formed inside it, each contact element (11) being in the form of a circular hollow cylindrical sleeve for mounting the plug connector (9), wherein the inner surface of the lateral surface surrounds the plug connector (9) to establish electrical contact.

15. The apparatus according to claim 13, characterized in that, The outer diameter of the contact element (11) substantially corresponds to the inner diameter of the wall (4a) of the connecting channel plus the groove (10), which is formed around the entire periphery and is intended to accommodate the potting compound (12).

16. The apparatus according to claim 13, characterized in that, The end (8c) of the connecting conduit (8b) of the conductor (8) is electrically connected via the contact element (11) to a plug-in connector (9) disposed inside the contact element (11).

17. The apparatus according to claim 16, characterized in that, The end (8c) of the conductor (8) has a conductive connection portion that is connected to the contact element (11) on the end face of the contact element (11) facing the stator (1).

18. A method of manufacturing an apparatus for driving a compressor for a gaseous fluid according to any one of claims 1 to 17, the method comprising the following steps when assembling the stator (1): - The stator core (2) is arranged to have an insulating element (6) and a conductor (8), the conductor (8) being wound to form a coil (5) and fitted with a connecting cable (8a) and a connecting conduit (8b), the connecting cable (8a) and the connecting conduit (8b) being arranged on the wall of the insulating element (6), the wall protruding beyond the stator core (2) in the axial direction; -A cover element (3) with mounting elements (4) is arranged on the end face of the stator core (2) aligned in the axial direction, each mounting element (4) being formed with a connecting channel completely enclosed by a wall (4a), wherein, The connection channels are each formed having a contact element (11), each contact element (11) being electrically connected to a connection line (8b) of the wire (8), and a plug-in connector (9) is inserted into each of the contact elements (11), and - The following volumes are at least regionally filled using a potting compound (12): namely, the volume formed between the stator core (2), the cover element (3), and the insulating element (6), and the volume formed between the wall (4a) of the mounting element (4) and the contact element (11), and - The rotor and stator (1) are arranged on a common longitudinal axis (7), wherein the stator (1) encloses the rotor in the radial direction.

19. The method according to claim 18, characterized in that, During the filling process, a potting compound (12) is used to at least regionally fill the following volumes: namely, the volumes enclosed by the capping element (3) and the twisted sections of the conductors (8), the twisted sections of the conductors (8) being wound to form coils (5) and aligned in the direction of the end face of the stator (1), wherein the volumes formed between the stator core (2), the capping element (3) and the insulating element (6), the volumes formed between the wall (4a) of the mounting element (4) and the contact element (11), and the volumes enclosed by the capping element (3) and the twisted sections of the conductors (8), the twisted sections of the conductors (8) being wound to form coils (5) and aligned in the direction of the end face of the stator (1).

20. Use of an apparatus for driving a compressor according to any one of claims 1 to 17, wherein, The compressor is used to compress gaseous fluid, and the device is used as a compressor for refrigerant in the refrigerant circuit of a motor vehicle's air conditioning system.

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