Stator of an electric motor for driving a refrigerant compressor

Abstract

To provide a stator capable of producing the necessary axial and lateral tolerance compensation for contact. [Solution] The conductor wire creates coils divided into at least three phases, a base insulator is formed between the stator core and the wound coils, each coil strand has two wire ends, and includes a base plate as a support element for the stator core and connecting elements, a first connecting element installed on the base plate and connected to each coil strand or the first wire end of each coil through a connecting element to connect all of the coils or coil strands to each other, and a coil connecting device connected to the coil strands or the second wire end of the coil to connect all of the coils or coil strands to each other of this phase, and the coil connecting device is connected to the wire ends of the wound coils or coil strands such that there is a gap between the base insulator and the coil connecting device.

Description

Technical Field

[0001] The present invention relates to a stator of an electric motor for driving a refrigerant compressor, and the present invention is suitable for use in refrigerant compressors for chemical refrigerants and natural refrigerants in mobile applications.

Background Art

[0002] Previous contacts of the individual coils and phases of the stator generally used a coil distributor ring firmly connected to other stator components. When the stator is in direct contact with a motor control device (inverter), such a type of rigid coil distributor ring cannot be used. In this case, the necessary axial and lateral tolerance compensation for contact cannot be used.

Summary of the Invention

Problems to be Solved by the Invention

[0003] An object of the present invention is to provide a stator capable of generating the necessary axial and lateral tolerance compensation for contact.

Means for Solving the Problems

[0004] The stator of an electric motor for driving a refrigerant compressor according to an embodiment for solving the above problems has a stator core (3) having a stator yoke that is substantially hollow cylindrical, with coil webs uniformly distributed along its inner circumference and radially inward with respect to its cross-section. The conductor wire is wound around the coil web to generate coils divided into at least three phases. A base insulator is formed between the stator core and the wound coils. When each of the wound coils or several of the coils are connected in series to the strands of the coils, each strand of the coil has two wire ends that project axially from the base insulator of the stator with respect to the circumferential axis of the stator yoke; and a base plate as a support element for the connecting elements, installed on the base plate and connected to the first wire ends of each strand of the coils or the wire ends that project axially from the base plate of each coil through the connecting elements to connect all the coils or the strands of the coils to each other. As an additional connecting element installed on the base plate, each is connected to the strands of the coils of the phase or the second wire ends of the coils to have an additional connecting element having a connecting element that connects all the coils or the strands of the coils of this phase to each other, including a coil connecting device. The coil connecting device is connected to the wire ends of the wound coils or the strands of the coils that project axially from the base plate such that there is a gap between the base insulator and the coil connecting device.

[0005] The fastening type and the remaining gap between the switching ring and the base insulator allow for both axial and lateral tolerance compensation, so the coil connecting device is also referred to as a "floating" coil connecting device and, in a preferred embodiment, as a "floating" coil connecting ring.

[0006] Due to the advantages of the axial and lateral tolerances, direct contact between the stator and the motor control unit (inverter) is possible. According to an advantageous embodiment of the present invention, each of the connecting elements that connect the phase coils or the coil strands to each other has a connection portion for connecting the same phase to a line element that forms an interface to the motor control unit (inverter). Thus, this connection portion allows an electrical connection between the wire ends of the coil or the coil strands and the electrical line elements of the interface to the motor control unit.

[0007] Generally, the coil connecting device is filled with potting material. In order to insulate the components from the refrigerant and from each other, after winding and connecting the coil or the coil strands to the connecting element, potting occurs with a pre-mounted floating coil connecting device. Potting can strengthen the connection points between the individual energizing elements. In this way, the coils or the coil strands can be connected simultaneously through a star connection and the coils or the coil strands of each phase, ensuring sufficient space and guaranteeing complete insulation between each energizing part.

[0008] According to the concept of the present invention, each of the coils or coil strands of the stator is connected as a star point connection through a first connection element to the coils or coil strands of the stator that operate in parallel. Preferably, a bus bar that connects each coil or each coil strand of each phase to a different coil or a different coil strand from each other to form the star point connection is used for such a purpose. According to an advantageous embodiment, the bus bar has a basic shape of an open arc and is uniformly distributed along the circumference or arc length thereof, and has a plurality of radially outwardly protruding connection elements each having an outer end that accommodates the first wire end of the coil or coil strand. In this case, since the total number of such connection elements of the bus bar corresponds to the total number of coils or coil strands of the stator, the bus bar can contact all the coils or coil strands of the stator through the connection elements and electrically connect them to each other.

[0009] The additional connection elements are similarly each formed as a bus bar having a basic shape of an open arc, uniformly distributed along the circumference or arc length thereof, and having a plurality of radially outwardly protruding connection elements each having an outer end that accommodates the second wire end of the coil. Such a bus bar is designed to generate the connection of all the coils or coil strands of each phase so that the coils or coil strands can operate simultaneously. Also, these three bus bars are preferably designed to allow connection to electrical line elements respectively for connection to an inverter which is a motor drive control unit.

[0010] In the case of a busbar that connects the coils or the strands of the coils of each phase to each other, the total number of the connecting elements leading to the coils or the strands of the coils of this phase corresponds to the total number of the coils or the strands of the coils of this phase. Advantageously, the radii of the arc shapes of the various busbars are different, and the busbars are arranged such that the arc shapes of the various busbars have the same center point or the center points of the arc shapes are located on the same axis that is at least perpendicular to the plane of the arc shapes.

[0011] In a preferred embodiment of the present invention, the busbar that connects all the coils of the stator to each other to show a star point connection is arranged radially outermost and consequently has a larger radius, a larger circumference or a larger arc length than all the other busbars respectively. Also, the open arc of the arc-shaped portion of this busbar has a substantially larger center point angle than the open arcs of the other busbars and consequently has a larger circumferential angle. According to an embodiment of the present invention, the busbar for star point connection is also formed to be circularly closed.

[0012] Other busbars located further radially inward preferably have connecting elements that are formed to be further radially longer than the respective connecting elements of the outer busbar. Generally, the following applies. The further each busbar is arranged inward and the smaller the radius of the open arc of the busbar, the longer the connecting element protruding radially must be in order to create a connection to the second wire end of the coil belonging to each phase or the strand of the coil belonging to each phase.

[0013] Furthermore, the busbars formed to connect the coils or the strands of the coils of each phase are each advantageously designed to allow a connection to an electrical conductor for connection to an inverter which is a motor drive control unit. Therefore, in addition to the connecting elements described above, each such busbar has a radially inward connection portion for each phase to the electrical line element of the interface to the motor drive control unit. Preferably, an annular connection end is formed at the connection portion.

[0014] According to a particularly advantageous embodiment of the invention, the base plate is designed to provide a separate accommodation space for receiving and supporting the connecting element, and, where appropriate, also to provide an accommodation space for the connecting portion for connecting to the line element of the interface to the motor drive control unit. For example, a corresponding arcuate accommodation space having side walls that are at least partially arcuate with respect to the bus bar can be provided by a recess, and if the side walls that are at least partially arcuate are each located between two adjacent bus bars, the side walls simultaneously serve as a partition between the respective adjacent bus bars. Further, the base plate can have an accommodation space for the connecting end portions of the connecting portion. The side walls advantageously serve to support the connecting element and the connecting portion, and at the same time are spacers for the connecting element and the connecting portion that are radially guided onto one or more bus bars with respect to such a bus bar. Preferably, the side walls of the accommodation space are provided with grooves for supporting the connecting element and / or the connecting portion.

[0015] According to a preferred embodiment of the invention, the base plate itself has an annular shape with an outer edge where the outer ring is located. Since the outer ring is preferably a removable part, the wire ends can be guided to the connecting element or the bus bar respectively before assembling the outer ring and the base plate. Here, the wire ends can preferably pass between the outer ring and the outer edge of the base plate so that the wire ends can be electrically connected to the connecting element located on the base plate. After assembly, the outer ring serves as a boundary wall, and the entire area surrounded by the outer ring can be potted with resin.

[0016] According to another embodiment of the present invention, the annular base plate has an inner edge where three convex protrusions are formed and directed radially inward. Each of these convex protrusions on the inner circumference of the base plate forms, together with the corresponding bent portion of the inner side wall, a receiving space for one of the annular connecting ends in the connecting portion for the electrical line element of the interface to the motor drive control unit.

[0017] The preferred design concept of the "floating" coil connection ring allows the coils or coil strands of each phase to be connected to each other in a simple and efficient manner. For example, the most direct way to achieve the connection of such complex coils or coil strands divided into three stages is to use busbars to connect all the coils or coil strands to each other, and design a base plate that enables the individual phases to be connected to the line elements forming the interface to the motor control unit (inverter). The first busbar is connected to the side surfaces of each coil or each coil strand to perform a star point connection function for all the coils. This means that all the coils or coil strands are respectively connected through this element. This means that this busbar is designed to connect each coil or each coil strand of each phase to different coils or different coil strands from each other. The remaining other busbars, three busbars in the case of three phases, are used to generate connections assigned to the phases. Such busbars are designed not only to operate all the coils or coil strands of the phase simultaneously, but also to be connectable to the electrical conductors connected to the motor drive control unit.

[0018] In the case of such a type of wiring pattern, a certain coil connection ring of the base plate shows an advantageous design solution. The base plate to which a removable outer ring is preferably attached serves as a support element for the connection elements of the coils or coil strands and the electrical line elements of the interface to the motor control unit.

[0019] According to another embodiment of the present invention, the sealed tube is inserted into a coil connection device into which electrical line elements, preferably electrical connection pins (E-pins) showing the interface between the stator and the inverter, are inserted respectively. The effect of the sealed tube is to insulate the line elements in a sealed environment and to provide a fixing area for an O-ring for sealing the inside of the sealed environment to the inverter.

Brief Description of the Drawings

[0020] Additional details, features, and advantages of embodiments of the present invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

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Figure 10

Figure 11

DETAILED DESCRIPTION OF THE INVENTION

[0021] FIG. 1 shows a side view of a stator (1) of an electric motor for driving a refrigerant compressor, which stator has a coil connection device (2) also referred to as a floating coil connection ring. The stator (1) includes a stator core (3) having a stator yoke, and the stator core (3) is substantially in the shape of a hollow cylinder, with coil webs uniformly distributed along the inner circumference thereof and radially inwardly of its cross-section. Although not shown in FIG. 1, due to the uniformly distributed arrangement of the coil webs, conductor wires are wound around the periphery of the coil webs distributed along the periphery of the stator core to form coils (4). The distribution of the coils (4) shown in FIG. 1 indicates that a total of 12 coils are arranged inside the stator core. The coils (4) are divided into three phases (4.1, 4.2, 4.3), and each phase is composed of 4 coils. A base insulator (5) is formed between the stator core (3) and the wound coil (4), and each wound coil (4) has two wire ends (6) that axially project the base insulator (5) of the stator (1) with respect to the cylinder axis of the stator yoke, which is in the shape of a hollow cylinder. The coil connection device (2) is connected to the wire ends (6) of the wound coil (4) that axially project the base insulator so that a defined interval (7) is maintained between the base insulator (5) and the coil connection device (2). Interconnection with coils connected in series is also possible. In such a configuration not shown, not all coils have two wire ends that axially project the base insulator, but rather each coil has strands.

[0022] The coil connection device (2) includes a base plate (8) that is substantially annular as a support element for a connection element that is connected to a wire end (6) protruding in the axial direction of the coil. Here, the wire end (6) passes between an outer ring (9) that limits around the coil connection device (2) and the outer edge of the base plate (8), so that the wire end (6) can be electrically connected to the connection element located on the base plate (8). The outer ring (9) is preferably designed as a removable part from the base plate (8). When mounting the coil connection device (2), before the outer ring (9) is attached to the outer edge of the base plate (8), each of the wire or the wire end (6) can be easily guided through the outer edge of the coil of the base plate (8) to the connection element. After the assembly of the coil connection device (2), the outer ring (9) also serves as a boundary wall for resin potting of the entire area surrounded by the outer ring (9).

[0023] Figure 2 shows a plan view of the stator (1) and the coil connection device (2) connected to the wire ends (6) of the stator coils, which is formed in the form of a floating coil connection ring. The design concept of the floating coil connection ring (2) enables the coils of each phase to be connected to each other in the simplest and most effective way. The most direct path for implementing such a complex connection of the coils separated into three phases (4.1, 4.2, 4.3) is to use bus bars (10, 11.1, 11.2, 11.3) as connection elements, and design the base plate (8) so that all the coils can be connected to each other using the bus bars, and each phase (4.1, 4.2, 4.3) can be connected to a line element that forms an interface to the motor control unit (inverter).

[0024] Each of the busbars (10, 11.1, 11.2, 11.3) has an open arc shape with connecting elements (12, 13.1, 13.2, 13.3) protruding radially outward, and the radii of the arc shapes of the various busbars (10, 11.1, 11.2) are different. The busbars (10, 11.1, 11.2, 11.3) are arranged such that the arc shapes of the various busbars (10, 11.1, 11.2, 11.3) have the same center point or the center points of the arc shapes are located on the same axis that is at least perpendicular to the plane shown in FIG. 2. According to FIG. 2, the radially protruding connecting elements (12, 13.1, 13.2, 13.3) are each formed by a connecting element having a fork-type end. The busbar (10) arranged most radially outward has a larger radius, a larger circumference or a larger arc length respectively compared to all other busbars (11.1, 11.2, 11.3). Also, the open arc of the arc-shaped portion of this busbar (10) has a substantially larger center point angle than the open arcs of the other busbars (11.1, 11.2, 11.3), and as a result, a larger circumferential angle. Overall, a total of 12 radially outward protruding connecting elements (12) are uniformly distributed along the circumference or arc length of the external busbar (10). At the wire ends of the coils arranged correspondingly, the busbar (10) is connected to one side of each of the 12 coils. According to FIG. 2, each connecting element (12) of the external busbar (10) has a fork-type end, and when the wire end (6a) is connected to the busbar (10), it is received in the fork-type end of the connecting element (12). In relation to the direction of winding the coil, this is always the same wire end (6a) of the coil. According to the representation of FIG. 2, this is always the right wire end (6a). In such a manner, the external busbar (10) forms a so-called star point connection for all 12 coils of the stator. This means that this busbar (10) is designed in such a way as to connect each coil of each phase to each other.

[0025] The three other busbars (11.1, 11.2, 11.3) located further inward in the radial direction are used to generate connections related to the phases (4.1, 4.2, 4.3). Each of these busbars (11.1, 11.2, 11.3) is designed to generate the connection of all the coils of the phase so that the coils can operate simultaneously. For this purpose, each of these busbars (11.1, 11.2, 11.3) has four connection elements (13.1, 13.2, 13.3) protruding radially outward, and each of these connection elements is uniformly distributed along the circumference or arc length of the arc-shaped region of the corresponding busbar (11.1, 11.2, 11.3). Such connection elements (13.1, 13.2, 13.3) are formed to be longer radially than each of the twelve connection elements (12) of the external busbar (10) in each case. According to the embodiment illustrated in FIG. 2, for each of the busbars (11.1, 11.2, 11.3) of the phases (4.1, 4.2, 4.3), the connection elements (13.1, 13.2, 13.3) of each busbar (11.1, 11.2, 11.3) are designed such that each adjacent connection element (13.1, 13.2, 13.3) of the individual busbars (11.1, 11.2, 11.3) is aligned with each other at an angle of 90°. The more each busbar (11.1, 11.2, 11.3) is arranged further inward and the smaller the radius of the open arc of the busbar, the longer the connection elements (12, 13.1, 13.2, 13.3) protruding radially must be in order to generate the connection - located on the left side - to the wire ends (6b) of the coils belonging to each phase (4.1, 4.2, 4.3). For this purpose, each left wire end (6b) of the coil is received in the fork-shaped end of a corresponding connection element (13.1, 13.2, 13.3) of one of the busbars (11.1, 11.2, 11.3) that connects the coils of the phase (4.1, 4.2, 4.3). Also, these three busbars (11.1, 11.2, 11.3) are designed to allow connection to an electrical conductor for connection to an inverter which is a motor drive control unit respectively.For this purpose, each such bus bar (11.1, 11.2, 11.3) has a radially inward connection (14.1, 14.2, 14.3) for each phase to the electrical line element of the interface to the motor drive control unit. The said connections (14.1, 14.2, 14.3) have an annular connection end as shown in FIG. 2. The base plate (8) is designed to provide the arc-shaped accommodation space for the bus bars (10, 11.1, 11.2, 11.3) by means of a recess, and the side walls (15a, 15b, 15c, 15d, 15e) of the bus bar, which are at least partially arc-shaped, serve simultaneously as the partition walls (15b, 15c, 15d) between two adjacent bus bars (11.1, 11.2; 11.2, 11.3) as long as they are located between two adjacent bus bars, such as the central side walls (15b, 15c, 15d). Further, the base plate has the accommodation spaces (16.1, 16.2, 16.3) for the annular connection ends of the connections (14.1, 14.2, 14.3). In the plan view according to FIG. 2, the base plate itself has an essentially circular ring shape with an outer edge where the essentially removable outer ring (9) is located and an inner edge where three convex protrusions are formed that extend radially inward. Each of these protrusions on the inner circumference of the base plate forms, together with the corresponding bent part of the inner side wall (15e) aligned axially, an accommodation space (16.1, 16.2, 16.3) for one of the annular connection ends in the connections (14.1, 14.2, 14.3).

[0026] FIG. 3 is a perspective view of the star point connection bus bar (10) as an individual component. The bus bar (10) serves the star point connection function for a total of 12 coils, all of which are connected by this individual component. Thus, starting from the basic shape of an open arc, the bus bar (10) has a total of 12 connecting elements (12) that protrude radially outward and have fork-shaped ends that each accommodate one wire end, and are uniformly distributed along the circumference or arc length of the bus bar (10). The uniform distribution of the connecting elements along the arc results in adjacent connecting elements (12) of the bus bar (10) being aligned with each other at an angle of 30° and including connecting elements (12a, 12b) that face each other at the two open ends of the arc in each case. In the perspective view, starting from the upper side of the arc-shaped region of the bus bar (10), initially the connecting elements (12) are predominantly changed as protrusions radially outward in the axial direction by a convex curvature and are directly adjacent to the upper side of the bus bar (10). The fork-shaped ends (17) of the connecting elements (12) are aligned such that a wire end extending axially can flow into the fork-shaped ends (17) from below, that is, starting from the coils of the stator core. In this case, the fork-shaped ends (17) are not located in the same plane as the arc-shaped region of the bus bar (10) but are located slightly above. The position of the connecting elements (12) on the arc-shaped region of the bus bar (10) facilitates the movement of the connecting elements (12) across one or more side walls or partitions when the bus bar is located in the accommodation space of the base plate.

[0027] Figure 4 shows a plan view of an array of three busbars (11.1, 11.2, 11.3). Each busbar has four connecting elements (13.1, 13.2, 13.3) for all four coils of a phase, and each phase also has connecting parts (14.1, 14.2, 14.3) for connection to an electrical conductor. The busbars (11.1, 11.2, 11.3) shown in Figure 4 are each designed to generate a connection related to a phase, and by doing so, all the coils of the phase can be connected to each other to operate these coils simultaneously. Therefore, as described above, each of these busbars (11.1, 11.2, 11.3) has an open arc shape with connecting elements (13.1, 13.2, 13.3) protruding radially outward. The arc-shaped regions of the busbars (11.2, 11.2, 13.3) have the same center point, and the arc-shaped radii of the various busbars (11.1, 11.2, 11.3) are different. The smaller the radius of the busbars (11.1, 11.2, 11.3), the longer the connecting elements (13.1, 13.2, 13.3) become radially. Also, the arc-shaped regions of the various busbars (11.1, 11.2, 11.3) are arranged offset from each other in the circumferential direction or arc direction. Both ensure that the arrangement of a total of twelve fork-shaped ends (18.1, 18.2, 18.3) of the connecting elements (13.1, 13.2, 13.3) is evenly distributed along the circumference of a virtual arc having a circumferential angle of 360°.

[0028] Starting from the upper side of the arc-shaped region of each bus bar (11.1, 11.2, 11.3), each connecting element (13.1, 13.2, 13.3) is initially changed by a convex curvature as a predominantly axially radially outward protrusion and is directly adjacent to the upper side of each bus bar (11.1, 11.2, 11.3). The fork-shaped ends (18.1, 18.2, 18.3) of the connecting elements (13.1, 13.2, 13.3) are aligned so that the axially extending wire ends can flow in from below, that is, starting from the coils of the stator core, into the fork-shaped ends (18.1, 18.2, 18.3). In this case, the fork-shaped ends (18.1, 18.2, 18.3) are not located in the same plane as the arc-shaped region of each bus bar (11.1, 11.2, 11.3), but are located above it. The positions of the connecting elements (13.1, 13.2, 13.3) on the arc-shaped regions of the bus bars (11.1, 11.2, 11.3) facilitate the movement of the connecting elements (13.1, 13.2, 13.3) across one or more side walls or partitions if all the bus bars (10, 11.1, 11.2, 11.3) are located in the accommodation space of the base plate.

[0029] Each bus bar shown in FIG. 4 has a radially inward connecting part (14.1, 14.2, 14.3) with an annular end as an additional connecting element. This provides an annular connection for each phase and enables this phase to be connected to an electrical line element that can be connected to an inverter, which is a motor drive control unit. The three connecting parts (14.1, 14.2, 14.3) are distributed only in a region less than half of the inner circumference of the base plate. The connecting part (14.1) of the bus bar located outermost in the representation of FIG. 4 and having the largest radius of its arc region here is arranged centrally within this array.

[0030] FIG. 5 is a perspective view of the base plate (8) together with the outer ring (9). The base plate (8) performs the function of a support element for the bus bars described above and for the electrical line elements for connection to the inverter.

[0031] The base plate (8) essentially has a circular ring shape with an outer edge where the outer ring (9) is arranged and an inner edge with three convex protrusions that extend radially inward. Together with the corresponding curved portions of the inner sidewall (15e) and the tiles, these respective bulging protrusions on the inner circumference of the base plate form accommodation spaces (16.1, 16.2, 16.3) for the annular connecting ends of the connecting parts that connect the phases to each line element not shown in FIG. 5, where each line element is provided as an interface to the motor control unit. Within each accommodation space (16.1, 16.2, 16.3), circular holes (19.1, 19.2, 19.3) are formed that penetrate the base plate for accommodating each line element. The three accommodation spaces (16.1, 16.2, 16.3) are distributed only in a region less than half of the inner circumference of the base plate. The centrally located accommodation space (16.1) has the largest radius of the arc-shaped regions of the three busbars with the corresponding connecting ends, and thus is provided for the annular connecting end of the outermost busbar.

[0032] A total of four arc-shaped accommodation spaces (20, 21.1, 21.2, 21.3) are formed in the base plate (8) for arc-shaped busbars (10, 11.1, 11.2, 11.3) of the same arc shape at the center point. The first external accommodation space (20) is provided for the external busbar (10) (see Fig. 2). The second external accommodation space (21.1), which is formed inside the first accommodation space (20) to accommodate a busbar for connecting phase coils adjacent in the radial direction, forms an arc having a smaller circumferential angle than the arc of the first accommodation space (20) by having a smaller central angle, and the first arc-shaped accommodation space (20) is not located along the entire arc length beside the second accommodation space (21.1) which is arc-shaped. In the region where the accommodation spaces (20, 21.1) are located adjacent to each other, they are separated from each other by an arc-shaped partition wall (15b). The additional third accommodation space (21.2), which is adjacent to the second accommodation space (21.1) in the radial direction from the inside of the second accommodation space (21.1) and is provided to accommodate an additional busbar for connecting phase coils, is arranged offset in the circumferential direction or arc direction with respect to the second accommodation space (21.1), and the arc-shaped accommodation spaces (21.1, 21.2) are not located beside each other along the entire arc length. In the region where the second accommodation space (21.1) and the third accommodation space (21.2) are located adjacent to each other, they are separated from each other by an arc-shaped partition wall (15c). The additional fourth accommodation space (21.3), which is adjacent to the third accommodation space (21.2) in the radial direction from the inside of the third accommodation space (21.2) and is provided to accommodate an additional busbar for connecting phase coils, is arranged offset in the circumferential direction or arc direction with respect to the third arc-shaped accommodation space (21.2) and the second accommodation space (21.1). In the region where the third accommodation space (21.2) and the fourth accommodation space (21.3) are located adjacent to each other, they are separated from each other by an arc-shaped partition wall (15d).

[0033] In addition, a number of depressions are formed in the base plate for the connecting elements aligned in the radial direction and the radially aligned portions of the connecting parts, each of which is formed in the side walls (15a, 15b, 15c, 15d) basically by rectangular grooves (22) or by several spaced grooves arranged alternately in the radial direction. These depressions are basically formed in several partition walls (15a, 15b, 15c, 15d). Some of the grooves (22) are provided for arranging the radially aligned regions of the connecting parts that serve to connect the phases to the electrical line elements.

[0034] To connect to the base plate (8), the outer ring (9) has at its lower edge radially inner protruding latching elements (23) that are regularly distributed over the entire circumference and have a substantially trapezoidal surface with a decreasing width towards the inside. However, each of the latching elements (23) has a concave curvature at one of its edges. The concave curvature provides a feed-through opening (25) for the wire ends of the stator coil together with the groove of the base plate.

[0035] Figure 6 is a plan view showing the outer ring (9) as a single part away from the base plate. The outer ring (9) is removable from the base plate and is designed as a part that allows the wire to be guided to the bus bar. After assembling the coil connection ring, the outer ring (9) also serves as a boundary wall for the resin for potting the entire area.

[0036] The concave curvature (24) forms a feed-through opening for the wire ends that are axially aligned together with the corresponding opposite regions of the base plate. Also, since the number of radially inner protruding latching elements (23) regularly distributed along the entire circumference of the outer ring (9) corresponds to twice the number of coils, it corresponds to a total of 24, which is the total number of wire ends of the coils.

[0037] FIG. 7 illustrates a sealing tube (26) for an electrical connection pin. An electrical connection pin (E-pin), not shown in FIG. 7, is mounted in one of the sealing tubes (26) as an example of an electrical line element. The effect of the sealing tube (26) is to insulate the electrical connection pin (E-pin) in a sealed environment and to provide a mounting area for an O-ring for sealing the interior of the sealed environment to the inverter.

[0038] One of the electrical connection pins (E-pin) (27) is shown in FIG. 8. The electrical connection pin (27) is an electrical conductor showing the interface between the stator and the motor drive system, i.e., the inverter.

[0039] Different from FIG. 5, which is a perspective view of the base plate (8) together with the outer ring (9), FIG. 9 illustrates a perspective view of the entire coil connection device (2) without potting and wire ends, with the inserted busbars (10, 11.1, 11.2, 11.3), the sealing tube (26) and the electrical connection pin (27). The base plate (8) as a support element for the busbars (10, 11.1, 11.2, 11.3) and the connection pins (27) for connecting to the inverter has not only the necessary depressions (20, 21.1, 21.2, 21.3) and grooves (22) for supporting and spacing apart the electrical conductive busbars (10, 11.1, 11.2, 11.3), the connection elements (12, 13.1, 13.2, 13.3) or the connections (14.1, 14.2, 14.3), but also the annular ends of the connections (14.1, 14.2, 14.3) and the necessary accommodation spaces (16.1, 16.2, 16.3) for the connection pins (27) as electrical line elements. In this way, the coils can be connected simultaneously through star connection and the coils of each phase, and sufficient space is ensured to guarantee complete insulation between each energized part.

[0040] Figure 10 shows the coil connection device (2) after the potting material (28) has been cast into the floating coil connection ring pre-mounted after winding to insulate the components from the refrigerant and from each other. Potting strengthens the connection points between individual energized elements. In this case, the holes (19.1, 19.2, 19.3) for accommodating the line elements are kept free. Also, the outer ring (9) serves as an outer boundary wall for resin potting of the entire area surrounded by the outer ring. The inner side wall (15e) serves as an inner boundary wall for resin potting.

[0041] A perspective view of the completed stator (1) having a cylindrical stator core (3) and a coil connection device (2) filled with potting material (28) is shown in Figure 11. In this case, three connection pins (27), each inserted into a sealed tube (26), flow in together with the sealed tube (26) in the potted coil connection device and are electrically connected to the connection parts of the busbars of individual phases. The coil connection device (2) in the form of the illustrated embodiment of the coil connection ring (2) is connected to the wire ends (6) of the winding coil that axially project the base insulator (5). The corresponding spacing (7) between the base insulator (5) and the coil connection device (2) allows for axial tolerance compensation. At the same time, such a type of fastening also generates lateral tolerance compensation.

Description of the reference numerals

[0042] 1 Stator 2 Coil connection device, coil connection ring 3 Stator core 4 Coil 4.1 Phase, phase coil 4.2 Phase, phase coil 4.3 Phase, phase coil 5 Base insulator 6 Wire end 6a Wire end (for star point connection) 6b Wire end (for phase connection) 7 Spacing 8 Base plate 9 Outer Ring 10 Busbar, Star Point Connection 11.1, 11.2, 11.3 Busbar 12, 13.1, 13.2, 13.3 Connecting Elements 12a, 12b Connecting Elements at the Ends of the Open Arc 14.1, 14.2, 14.3 Connections 15a, 15d Side Walls 15b, 15c Side Walls, Partition Walls 15e Side Wall, Inner Side Wall 16.1, 16.2, 16.3 Accommodation Spaces 17 Fork-Type End of the Busbar (10) 18.1 Fork-Type End of the Busbar (11.1) 18.2 Fork-Type End of the Busbar (11.2) 18.3 Fork-Type End of the Busbar (11.3) 19.1, 19.2, 19.3 Line Element Accommodation Holes 20 Busbar (10) Accommodation Space 21.1 Busbar (11.1) Accommodation Space 21.2 Busbar (11.2) Accommodation Space 21.3 Busbar (11.3) Accommodation Space 22 Groove in the Side Wall 23 Latching Element of the Outer Ring (9) 24 Concave Curved Portion of the Latching Element (23) 25 Feed-Through Opening for the Wire End 26 Sealing Tube 27 Line Element; Electrical Connection Pin; E-pin 28 Potting Material

Claims

1. As a stator (1) of an electric motor for driving a refrigerant compressor, The stator (1) is, Substantially in the shape of a hollow cylinder, having a stator core (3) having a stator yoke with coil webs that are uniformly distributed along the inner circumference thereof and radially inwardly of its cross-section, the conductor wire being wound around the coil webs to form coils (4) divided into at least three phases, a base insulator (5) being formed between the stator core (3) and the wound coils, each of the wound coils or several of the coils (4) being connected in series to the strands of the coils, each strand of each coil (4) having two wire ends (6a, 6b) that project axially from the base insulator of the stator (1) with respect to the circumferential axis of the stator yoke, the stator core (3), and a base plate (8) as a support element for the connecting elements, the base plate (8) being installed and connected to the strand of the coil (4) or the first wire end (6a) of each coil (4) through a connecting element (12) to connect all the coils (4) or the strands of the coils to each other, and as an additional connecting element installed on the base plate (8), each being connected to the strand of the coil of the phase (4.1, 4.2, 4.3) or the second wire end (6b) of the coil (4) to connect all the coils or the strands of the coils of the phase (4.1, 4.2, 4.3) to each other, having an additional connecting element having connecting elements (13.1, 13.2, 13.3), including a coil connecting device (2), The coil connecting device (2) is connected to the wire ends (6a, 6b) of the wound coil (4) or the strands of the coil (4) such that there is a gap (7) between the base insulator (5) and the coil connecting device (2), The base plate (8) has a circular ring shape with an outer edge to which a removable outer ring (9) limiting the circumference of the coil connecting device (2) is attached, a stator (1) of an electric motor for driving a refrigerant compressor, characterized in that.

2. Each of the connecting elements that connect the coils (4) of the phase (4.1, 4.2, 4.3) or the strands of the coil (4) to each other has a connecting portion (14.1, 14.2, 14.3) for connecting in the same phase as the line element (27) that forms an interface to the motor control unit. The stator (1) of the electric motor for driving a refrigerant compressor according to claim 1, characterized in that.

3. The coil connecting device (2) is filled with a potting material to insulate the electrically conductive components from the refrigerant and from each other. The stator (1) of the electric motor for driving a refrigerant compressor according to claim 1 or 2, characterized in that.

4. The first connecting element is formed as a bus bar (10) having a basic shape of an open arc, uniformly distributed along the circumference or arc length thereof, and having a plurality of the connecting elements (12) protruding radially outward, each having an outer end that houses the first wire end (6a) of the coil (4). The total number of the connecting elements (12) of such a bus bar (10) corresponds to the total number of the coils (4) or the strands of the coil of the stator (1). The stator (1) of the electric motor for driving a refrigerant compressor according to claim 1, characterized in that.

5. The additional connecting elements are each formed as a bus bar (11.1, 11.2, 11.3) having a basic shape of an open arc, uniformly distributed along the circumference or arc length thereof, and having a plurality of the connecting elements (13.1, 13.2, 13.3) protruding radially outward, each having an outer end that houses the second wire end (6b) of the coil (4). The total number of the connecting elements (13.1, 13.2, 13.3) corresponds to each of the total number of the coils or the strands of the coil of the phase (4.1, 4.2, 4.3) for each of such bus bars (11.1, 11.2, 11.3). The stator (1) of the electric motor for driving a refrigerant compressor according to claim 4, characterized in that.

6. The radii of the arc shapes of the various busbars (10, 11.1, 11.2, 11.3) are different, and the busbars (10, 11.1, 11.2, 11.3) are arranged such that the arc shapes of the various busbars (10, 11.1, 11.2, 11.3) have the same center point, or the center points of the arc shapes are located on the same axis that is at least perpendicular to the plane of the arc shape. The stator (1) of the electric motor for driving a refrigerant compressor according to claim 5, characterized in that.

7. The base plate (8) is designed to provide separate accommodation spaces (20, 21.1, 21.2, 21.3) for accommodating and supporting the connecting elements, and, where appropriate, also provide accommodation spaces (16.1, 16.2, 16.3) for the connecting portions (14.1, 14.2, 14.3) for connecting to the line elements (27) of the interface to the motor drive control unit. The stator (1) of the electric motor for driving a refrigerant compressor according to claim 2, characterized in that.

8. The wire ends (6a, 6b) pass between the outer ring (9) and the outer edge of the base plate (8), and the wire ends (6a, 6b) are capable of being electrically connected to the connecting elements located on the base plate (8). The stator (1) of the electric motor for driving a refrigerant compressor according to claim 1, characterized in that.

9. The annular base plate (8) has an inner edge formed with a number of radially inward protrusions corresponding to the number of phases, and each of these protrusions on the inner circumference of the base plate (8), together with the corresponding bent portions of the inner side wall (15e), forms the accommodation space (16.1, 16.2, 16.3) for one of the annular connecting ends of the connecting portions (14.1, 14.2, 14.3) for the electrical line elements of the interface to the motor drive control unit. The stator (1) of the electric motor for driving a refrigerant compressor according to claim 7, characterized in that.

10. As the stator (1) of the electric motor for driving a refrigerant compressor, The stator (1) is, As a stator core (3) having a stator yoke that is substantially hollow cylindrical, has coil webs uniformly distributed along the inner circumference thereof, and has coil webs directed radially inward with respect to its cross-section, conductor wires are wound around the coil webs to generate coils (4) divided into at least three phases, a base insulator (5) is formed between the stator core (3) and the wound coils, and each of the wound coils, or when several of the coils (4) are connected in series to coil strands, each strand of each coil has two wire ends (6a, 6b) that axially project the base insulator of the stator (1) with respect to the circumferential axis of the stator yoke. The stator core (3), and a base plate (8) as a support element for the connecting elements, a first connecting element installed on the base plate (8) and connected to each strand of each coil (4) or the first wire end (6a) of each coil (4) through a connecting element (12) to connect all the coils (4) or each strand of each coil (4) to each other, and as an additional connecting element installed on the base plate (8), each connected to the strand of the coil (4) of each phase (4.1, 4.2, 4.3) or the second wire end (6b) of the coil (4), having additional connecting elements having connecting elements (13.1, 13.2, 13.3) that connect all the coils (4) of the phase (4.1, 4.2, 4.3) or the strands of the coil (4) to each other, including a coil connecting device (2). The coil connecting device (2) is connected to the wire ends (6a, 6b) of the wound coils (4) or the strands of the coils (4) such that a gap (7) exists between the base insulator (5) and the coil connecting device (2). Each of the connecting elements that connect the coils (4) of each phase (4.1, 4.2, 4.3) or the strands of the coils (4) to each other has connecting portions (14.1, 14.2, 14.3) for connection of the same phase to line elements (27) that form an interface to a motor control unit. The stator (1) of an electric motor for driving a refrigerant compressor, wherein the connecting portions (14.1, 14.2, 14.3) have annular connecting ends.

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