Motor, electric compressor comprising same, and method for manufacturing said motor

Abstract

[Problem] To provide a motor that comprises a bus bar unit and that is capable of relaxing dimensional tolerance and positional tolerance. [Solution] A motor 4 comprises: a stator 21 comprising a core 22 and an insulator 27 which is provided to the core 22 and around which magnet wires 23 are wound; and a bus bar unit 26 formed by molding, with a resin, a bus bar which electrically connects the magnet wires 23 coming out of slots of the stator 21 and a three-phase terminal 33. The motor comprises: a keyway 31 which is formed on the outer periphery of the insulator 27; and a leg part 43 which is formed on the bus bar unit 26 and extends into the keyway 31. The width of a claw section 47 of the leg part 43 is smaller than the width of the keyway 31.

Description

Motor, Electric Compressor Equipped with the Same, and Method for Manufacturing the Same

[0001] The present invention relates to a motor including a bus bar unit formed by resin-molding a bus bar that electrically connects magnet wires emerging from respective slots of a stator to three-phase terminals, an electric compressor including the same, and a method for manufacturing the same.

[0002] Conventionally, a motor for driving a compression element of an electric compressor has been composed of a stator and a rotor that rotates inside the stator. Among these, the stator is composed of a core formed by laminating electromagnetic steel sheets, a plurality of teeth protruding from the core in the inner diameter direction, and magnet wires wound around each tooth. Since the core and the magnet wires need to be insulated, an insulator made of an insulating resin is provided at the end of the core, and the magnet wires are wound around this insulator to achieve insulation between the core and the magnet wires.

[0003] Further, at the end (lead side) of the stator, a bus bar unit in which a metal bus bar and three-phase terminals (terminals connected to an inverter) are resin-molded is provided, and the magnet wires emerging from respective slots of the stator are electrically connected to the three-phase terminals by the bus bar. In this case, the bus bar unit (referred to as a bus bar holder in the following document) was attached to the motor by engaging it with the core of the stator (see, for example, Patent Document 1).

[0004] On the other hand, the inside of the casing of the electric compressor is partitioned into a motor chamber and an inverter chamber by a partition wall. The motor is fixed in the motor chamber, and the inverter is attached to the inverter chamber. Then, the three-phase terminals of the bus bar unit are inserted from the motor chamber side into through-holes formed in the partition wall, and the tips thereof face the inverter chamber and are configured to be electrically connected to the inverter.

[0005] WO2020 / 013078

[0006] However, if the busbar unit is fixed to the motor in a way that prevents it from moving, as described in Patent Document 1 above, the degree of freedom of position is lost. Therefore, when assembling it into through holes formed in the casing partition or at the inverter connection points, high positional accuracy and dimensional accuracy of the parts are required, which leads to problems with ease of installation.

[0007] The present invention has been made to solve the aforementioned conventional technical problems, and aims to provide a motor equipped with a busbar unit that can relax dimensional tolerances and positional tolerances, an electric compressor equipped with the same, and a method for manufacturing the same.

[0008] The motor of the present invention comprises a stator having a core and an insulator provided on the core around which magnet wires are wound, and a busbar unit formed by molding busbars made of resin to electrically connect the magnet wires coming out of each slot of the stator to three-phase terminals, characterized in that it has a keyway formed on the outer circumference of the insulator or core, and legs formed on the busbar unit that enter into the keyway, the width of which is smaller than the width of the keyway.

[0009] The motor of the second invention is characterized in that the keyway in the above invention is formed on the outer circumference of the insulator.

[0010] The electric compressor of the third invention comprises a motor room in which the motors of each of the above inventions are housed, an inverter room in which an inverter for supplying power to the motor is attached, a partition wall separating the motor room and the inverter room, and a casing having through holes formed in the partition wall, wherein the busbar unit has a resin part for molding three-phase terminals, the three-phase terminals protruding from the resin part, passing through the through holes from the motor room side, and their tips facing the inverter room.

[0011] The electric compressor of the fourth invention is characterized by comprising an O-ring that seals the gap between the resin portion of the portion in which the three-phase terminal protrudes and the through hole in the partition wall, wherein the O-ring is inserted into the through hole from the inverter room side and held by the resin portion on the motor room side, and an O-ring retaining member is attached to the inverter room side of the partition wall.

[0012] The fifth invention of the electric compressor is characterized in that, in the above invention, the busbar unit is held by the partition wall with three-phase terminals inserted into through holes in the partition wall and a retaining member attached to the partition wall.

[0013] The sixth invention is a method for manufacturing an electric compressor comprising a motor room containing a motor, an inverter room equipped with an inverter for supplying power to the motor, a partition wall separating the motor room and the inverter room, and a casing having through holes formed in the partition wall, wherein the motor comprises a stator having a core and an insulator provided on the core around which magnet wires are wound, a busbar unit formed by molding busbars out of resin to electrically connect magnet wires coming out of each slot of the stator to three-phase terminals, a keyway formed on the outer circumference of the insulator or core, and legs formed on the busbar unit that enter into the keyway, the busbar unit having a resin part for molding the three-phase terminals, the three-phase terminals protruding from the resin part, the width of the legs of the busbar unit being smaller than the width of the keyway, and the three-phase terminals being inserted into the through holes from the motor room side, passing through the through holes and having the tips of the three-phase terminals facing the inverter room.

[0014] The seventh invention is a method for manufacturing an electric compressor, characterized in that, in the above invention, an O-ring that seals the gap between the resin part of the portion where the three-phase terminal protrudes and the through-hole in the partition wall is inserted into the through-hole from the inverter room side, the motor room side is held in place by the resin part, and an O-ring retaining member is attached to the inverter room side of the partition wall, and in this state the busbar unit is held in place by the partition wall.

[0015] According to the present invention and the sixth invention, a keyway is formed on the outer circumference of the insulator or core, and the busbar unit is provided with legs that enter into the keyway, and the width of these legs is made smaller than the width of the keyway, so that the busbar unit can rotate in the circumferential direction of the motor.

[0016] In other words, because the busbar unit has more flexibility in its position, even when it is used in an electric compressor such as the third invention, in which the three-phase terminals of the busbar unit are inserted into a through-hole in the partition wall from the motor room side, and the tips of the three-phase terminals are brought out through the through-hole to face the inverter room, the dimensional tolerances required for the busbar unit and the casing of the electric compressor, as well as the positional tolerances required when assembling the electric compressor, are relaxed. This makes it possible to improve the productivity of parts and the efficiency of assembly.

[0017] In this case, if the keyway is formed on the outer circumference of the insulator, as in the second invention, the problem of adverse effects on the motor's characteristics, as can occur when it is formed on the core, can be resolved.

[0018] Furthermore, as in the fourth and seventh inventions, an O-ring is provided to seal the gap between the resin part of the busbar unit where the three-phase terminals protrude and the through-hole in the partition wall. By configuring this O-ring to be inserted into the through-hole from the inverter room side and held in place by the resin part on the motor room side, the processability of the electric compressor casing is improved, and the insertion state of the O-ring can be confirmed from the inverter room side, thus improving quality. In addition, by attaching an O-ring retention member to the inverter room side of the partition wall, it is possible to prevent the O-ring from coming out of the through-hole and the inconvenience of refrigerant or oil entering the inverter room from the motor room.

[0019] Furthermore, as in the fifth invention, by configuring the busbar unit so that the three-phase terminals are inserted into the through-holes in the bulkhead and a retaining member is attached to the bulkhead, the position of the busbar unit is fixed and it can be stably attached to the bulkhead.

[0020] This is a schematic longitudinal cross-sectional side view of an electric compressor according to one embodiment, equipped with the motor of the embodiment (Embodiment 1). This is a side view of the stator and busbar unit constituting the motor of Figure 1. This is a perspective view of the busbar unit of the motor of Figure 2. This is a longitudinal cross-sectional side view of the main part of the motor of Figure 2. This is an enlarged front view of the legs of the busbar unit of the motor of Figure 2 and the keyway portion of the inverter. This is a plan view of the electric compressor of Figure 1 as seen from the inverter room side. This is a cross-sectional view taken along line A-A in Figure 6. This is a cross-sectional view taken along line B-B in Figure 6. This is a diagram illustrating the procedure for mounting the motor to the casing. This is a cross-sectional view corresponding to Figure 7 of an electric compressor of another embodiment (Embodiment 2). This is a cross-sectional view corresponding to Figure 8 of an electric compressor of another embodiment. This is a cross-sectional view corresponding to Figure 7 of yet another embodiment of an electric compressor (Embodiment 3). This is a cross-sectional view corresponding to Figure 8 of yet another embodiment of an electric compressor. This is a cross-sectional view corresponding to Figure 7 of yet yet another embodiment of an electric compressor (Embodiment 4). This is a cross-sectional view corresponding to Figure 8 of yet yet another embodiment of an electric compressor. This is an enlarged view of the winding connection part of an electric compressor illustrating yet yet another embodiment (Embodiment 5). This is a diagram illustrating the busbar unit in the embodiment of Figure 16. This is a plan view of the sealing member in the case of Figure 17. This is a plan view of the inverter chamber in the through-hole portion in the case of Figure 17. This is a diagram illustrating the installation procedure of the busbar unit in the case of Figure 17. This is a diagram illustrating another embodiment of the busbar unit corresponding to Figure 17 (Embodiment 6). This is a plan view of the sealing member in the case of Figure 21. This is a plan view of the inverter chamber in the through-hole portion in the case of Figure 21.

[0021] Embodiments of the present invention will be described in detail below with reference to the drawings.

[0022] Figure 1 is a schematic longitudinal cross-sectional side view of the electric compressor 1 equipped with the motor 4 of the embodiment, Figure 2 is a side view of the stator 21 and busbar unit 26 of the motor 4, Figure 3 is a perspective view of the busbar unit 26, and Figure 4 is a cross-sectional view of the main part of the motor 4.

[0023] (1) Electric Compressor 1 In Figure 1, the electric compressor 1 of the embodiment is an inverter-integrated scroll-type electric compressor in which a scroll compression element 3 as an example of a compression element and a motor 4 of the embodiment are housed in a metal casing 2 such as aluminum. The inside of the casing 2 is divided into a motor room 15 and an inverter room 17 by a partition wall 10, and the motor 4 is housed in the motor room 15 and fixed to the casing 2 by shrink fitting.

[0024] Furthermore, a scroll compression element 3 is also housed in the motor chamber 15. The scroll compression element 3 in this embodiment consists of a fixed scroll 6 fixed to the casing 2 and a movable scroll 7 that revolves around the fixed scroll 6 without rotating relative to it, due to the rotation shaft 8 of the motor 4. The spiral wrap 11 formed on the fixed scroll 6 and the spiral wrap 12 formed on the movable scroll 7 are arranged to interlock.

[0025] Refrigerant is introduced into the casing 2 from a refrigerant introduction passage (not shown) and is drawn in from the outside into a compression chamber formed between the two wraps 11 and 12. As this compression chamber narrows towards the center due to the orbital motion of the movable scroll 7, the drawn-in refrigerant is compressed and discharged from the center through the discharge chamber 14 and a refrigerant discharge passage (not shown). Also, because the inside of the casing 2 is at low pressure, refrigerant also passes around the motor 4, and the motor 4 is cooled by this refrigerant.

[0026] At the end of the casing 2, located on the opposite side of the scroll compression element 3, the inverter chamber 17 described above is formed, as shown in Figure 1, to house the inverter 16 for driving the motor 4. The three-phase terminal 33 of the busbar unit 26, which will be described in detail later, penetrates the partition wall 10 described above, which forms the bottom wall of the inverter chamber 17, and its tip faces into the inverter chamber 17 and is connected to a connection terminal 18 provided on the inverter 16. Since this connection terminal 18 and the three-phase terminal 33 are connected by press-fitting, the motor 4 and the inverter 16 are electrically connected, and power is supplied from the inverter 16 to the motor 4.

[0027] (2) Motor 4 Next, the motor 4 of the embodiment will be described. The motor 4 of the embodiment is a permanent magnet synchronous motor and consists of a stator 21 made of a core 22 made of multiple electromagnetic steel sheets laminated together, magnet wires 23 (windings; Figure 4) and insulators 25 and 27, and a magnet-embedded rotor 24 (also made of multiple electromagnetic steel sheets laminated together) which is fixed to the rotating shaft 8 and rotates inside the stator 21.

[0028] The core 22 of the stator 21 has multiple teeth 28 corresponding to the magnetic poles, and the slots 29 between each tooth 28 are shaped to be open toward the center (Figure 4). An insulator 25 is attached to the end of the core 22 on the scroll compression element 3 side, and an insulator 27 is attached to the end of the core 22 on the inverter chamber 17 side, and the magnet wire 23 is wound around these insulators 25 and 27.

[0029] As a result, the insulators 25 and 27 are fixed to the core 22, and are positioned between the core 22 and the magnet wire 23, providing insulation. In this embodiment, the insulators 25 and 27 are formed in an annular shape by injection molding of an insulating synthetic resin such as LCP, PPS, or PBT.

[0030] Furthermore, multiple keyways 31 (three in this embodiment) are formed on the outer circumferential surface of the insulator 27 in the embodiment, extending in the axial direction of the stator 21 (Figures 2 and 4). Note that the keyways 31 may be formed on the core 22 instead of the insulator 27. However, forming them on the insulator 27 as in this embodiment reduces the adverse effect on the characteristics of the motor 4 compared to forming them on the core 22.

[0031] (3) Busbar Unit 26 Next, the busbar unit 26, which is fixed to the inverter chamber 17 side of the stator 21, will be described. The busbar unit 26 is a connecting member for electrically connecting the magnet wires 23 coming out of each slot 29 of the core 22 of the stator 21 and the three-phase terminals 33 described above. It is made by molding a metal (conductive material) busbar 36 with a resin part 37 (insulating hard resin) that has the shape shown in Figure 3.

[0032] In this embodiment, the busbar 36 has an annular shape and is integrally provided with a plurality of winding connection parts 41 that protrude outward from the circle. Each winding connection part 41 is formed to correspond to the number of magnet wires 23 coming out of each slot 29. In addition, the aforementioned three-phase terminals 33 are arranged along the arc of the busbar 36 and their bases are electrically connected to the busbar 36.

[0033] The busbar 36 and the three-phase terminal 33 are then molded by the resin part 37 (inserter molding), forming a busbar unit 26 in which the busbar 36, the three-phase terminal 33, and the resin part 37 are integrated. In this case, the busbar 36 is embedded within the annular part 42 of the busbar unit 26, and each winding connection part 41 protrudes in the radial direction of the annular part 42, protruding from and exposed from the resin part 37.

[0034] Furthermore, only the bases of the three three-phase terminals 33 are embedded in the resin portion 37, and they protrude in the axial direction of the ring portion 42, with their tips exposed from the resin portion 37 (Figures 2 and 3). In this case, the resin portion 37 in the part from which each three-phase terminal 33 protrudes has a large-diameter portion 37A and a small-diameter portion 37B at its tip, and each three-phase terminal 33 protrudes and is exposed from this small-diameter portion 37B (Figure 3).

[0035] Furthermore, the annular portion 42 of the busbar unit 26 has multiple legs 43 (three in this embodiment) that extend radially outward (radially) from the outside of the circle of the annular portion 42 by integral molding of resin. In this case, one leg 43 is formed extending outward from a position opposite the circle of the annular portion 42 from the three-phase terminal 33, and the remaining two legs 43 are formed extending outward from the annular portion 42 where the three-phase terminals on both sides of the three-phase terminal 33 are located.

[0036] Each leg portion 43 is bent at a right angle in the opposite direction to the three-phase terminal 33, and their tips are designated as claw portions 47. On the other hand, the aforementioned keyway 31 of the insulator 27 is formed at positions corresponding to the claw portions 47 of each leg portion 43 of the busbar unit 26. Furthermore, the width of the claw portion 47 of the leg portion 43 is smaller than the width of the keyway 31 formed in the insulator 27 (Figure 5).

[0037] With the above configuration, when attaching the busbar unit 26 to the stator 21, the claw portions 47 of each leg portion 43 of the busbar unit 26 are inserted into the keyway 31 of the insulator 27 from the axial direction. At this time, the width of the claw portion 47 is smaller than the width of the keyway 31 of the insulator 27 (Figure 5), so the claw portion 47 is positioned to a certain extent so that it can move in the circumferential direction (circumferential direction of the motor 4) and the axial direction (axial direction of the motor 4) within the keyway 31. After inserting the claw portions 47 of the leg portions 43 of the busbar unit 26 into the keyway 31 of the insulator 27 and positioning them to a certain extent, the lead portions 23A of the magnet wires 23 coming out of each slot 29 are welded to the winding connection portion 41 of the busbar 36.

[0038] (4) Partition wall 10 of casing 2 The inverter chamber 17 described above is located at the end of casing 2 on the opposite side from the scroll compression element 3 when viewed from the motor 4, and is separated from the motor chamber 15 by a partition wall 10. The inverter 16 (circuit board) that drives the motor 4 is installed inside this inverter chamber 17. The inverter 16 passes through (penetrates) three through holes 51 formed in the partition wall 10 of casing 2, and is electrically connected to the motor 4 via the aforementioned three-phase terminal 33, one end of which faces from the motor chamber 15 to the inverter chamber 17, and the aforementioned connection terminal 18 on the inverter 16 side.

[0039] Figure 6 is a plan view of the electric compressor 1 as seen from the inverter room 17 side, Figure 7 is a cross-sectional view taken along line A-A in Figure 6, and Figure 8 is a cross-sectional view taken along line B-B in Figure 6. The inverter room 17 has an opening on the side opposite the partition wall 10, and this opening is closed by a cover 52 (Figure 6 shows the state with the cover 52 removed). This cover 52 is attached to the casing 2 after the inverter 16 is installed in the inverter room 17, but it does not create an airtight seal, so the inverter room 17 is at atmospheric pressure.

[0040] (5) O-ring 53 In Figures 1, 7, and 8, 53 is an O-ring made of an elastic material that serves as a sealing material. The O-ring 53 is inserted into each through-hole 51 from the inverter chamber 17 side, with the three-phase terminals 33 inserted into each through-hole 51 and its tip facing the inverter chamber 17. At this time, a chamfered portion 54 is formed on the partition wall 10 at the opening edge of each through-hole 51 on the inverter chamber side, making it easier to insert the O-ring into the through-hole 51. The motor chamber 15 side of the O-ring 53 is held by the large-diameter portion 37A (the stepped portion between the large-diameter portion 37A and the small-diameter portion 38B) of the resin portion 37 of the busbar unit 26. In this state, the O-ring 53 seals the gap between the small-diameter portion 37B of the resin portion 37 and the through-hole 51.

[0041] Then, an O-ring 53 retention member 56 is attached to the inverter chamber 17 side of the partition wall 10 in the area corresponding to the three through holes 51. In this embodiment, the retention member 56 consists of a metal plate member 57 attached to the inverter chamber 17 side of the partition wall 10 by bolts 59, and a resin anti-loosening ring 58 positioned between the plate member 57 and the O-ring 53 and fitted into the through holes 51. The anti-loosening ring 58 has a shape that matches the inclination of the chamfered portion 54 of the through hole 51. The plate member 57 also has three holes 61 through which each small diameter portion 37B passes.

[0042] (6) Assembly procedure for motor 4 Next, the assembly procedure for the motor 4 and inverter 16 of the electric compressor 1 configured as described above will be explained. The motor 4, to which the busbar unit 26 has been attached as described above, is housed in the motor chamber 15 of the casing 2 as shown by the arrow in Figure 9, with the busbar unit 26 facing the partition wall 10. The three-phase terminal 33 is inserted into the through hole 51 of the partition wall 10, and the tip of the three-phase terminal 33 is brought into the inverter chamber 17 by passing through the through hole 51.

[0043] Next, the core 22 of the motor 4 is fixed by shrink-fitting it to the inner surface of the casing 2. Here, the through-hole 51 has a dimension that allows the large-diameter portion 37A of the resin portion 37 of the busbar unit 26 to enter, and the stepped portion between the large-diameter portion 37A and the small-diameter portion 38B is located within the through-hole 51. Note that even if there is some error in the positional relationship between the busbar unit 26, the core 22, and the casing 2 at this time, since the busbar unit 26 is movable in the circumferential direction as described above, if the tip of the three-phase terminal 33 can enter the through-hole 51, then afterwards it enters the through-hole 51 in the order of the small-diameter portion 37B and the large-diameter portion 37A, and the three-phase terminal 33 can pass through the through-hole 51. Therefore, the dimensional tolerances required for the busbar unit 26 and the casing 2, and the positional tolerances required when assembling the electric compressor 1 are relaxed.

[0044] After that, the O-ring 53 is inserted into each through-hole 51 from the inverter chamber 17 side, and the motor chamber 15 side of the O-ring 53 is held by the stepped portion between the large-diameter portion 37A and the small-diameter portion 38B of the resin portion 37 of the busbar unit 26. In this state, the O-ring 53 is positioned in the gap between the small-diameter portion 37B of the resin portion 37 and the through-hole 51 to seal.

[0045] Next, the retaining ring 58 for preventing removal of the retaining member 56 is inserted into and fitted into each through-hole 51 to match the inclination of the chamfered portion 54. Next, the plate member 57 is arranged on the inverter chamber 17 side of the partition wall 10 in such a way that the small-diameter portion 37B of each three-phase terminal 33 is inserted into the hole 61 of the plate member 57, and is attached to the partition wall 10 with bolts 59. In this state, the busbar unit 26 is held by the partition wall 10. Also, since the retaining member 56 is provided on the inverter chamber 17 side of the O-ring 53, leakage of refrigerant and oil from the motor chamber 10 side to the inverter chamber 17 is prevented.

[0046] After that, the inverter 16 is housed and attached in the inverter chamber 17, and at the same time the connection terminal 18 is connected to one end of the three-phase terminal 33. And finally, the cover 52 is attached to the casing 2 to close it.

[0047] As described above, a key groove 31 is formed on the outer periphery of the insulator 27 (or the core 22), and the bus bar unit 26 is provided with a claw portion 47 of a leg portion 43 that enters the key groove 31. Since the width of the claw portion 47 of the leg portion 43 is set to a dimension smaller than the width of the key groove 31, the bus bar unit 26 can rotate in the circumferential direction of the motor 4.

[0048] That is, since there is a degree of freedom in the position of the bus bar unit 26, even in the case of the electric compressor 1 in which the three-phase terminals 33 of the bus bar unit 26 are inserted into the through hole 51 of the partition wall 10 from the motor chamber 15 side and the tip of the three-phase terminals 33 faces the inverter chamber 17 through the through hole 51, the dimensional tolerances required for the bus bar unit 26 and the casing 2 of the electric compressor 1, and the positional tolerances required when assembling the electric compressor 1 are relaxed. As a result, the productivity of the parts can be improved and the assembly workability can be improved.

[0049] In this case, in the embodiment, since the key groove 31 is formed on the outer periphery of the insulator 27, the problem of adversely affecting the characteristics of the motor 4 as in the case of forming it on the core 22 can also be solved.

[0050] Further, in the embodiment, an O-ring 53 for sealing the gap between the small-diameter portion 37B of the resin portion 37 of the bus bar unit 26 where the three-phase terminals 33 protrude and the through hole 51 of the partition wall 10 is provided, and this O-ring 53 is inserted into the through hole 51 from the inverter chamber 17 side and the motor chamber 15 side is held at the stepped portion between the large-diameter portion 37A and the small-diameter portion 37B of the resin portion 37. Therefore, there is no need to configure a stepped shape for holding the O-ring 53 in the through hole 51, the workability of the casing 2 of the electric compressor 1 is improved, and since the insertion state of the O-ring 53 can be confirmed from the inverter chamber 17 side, the quality can also be improved.

[0051] Further, since a configuration is adopted in which a retaining member 56 for the O-ring 53 is attached to the inverter chamber 17 side of the partition wall 10, it is possible to prevent the inconvenience that the O-ring 53 is pushed out from the through hole 51 into the inverter chamber 17 by the pressure on the motor chamber 15 side and comes off, and refrigerant and oil enter the inverter chamber 17 from the motor chamber 15.

[0052] Furthermore, in this embodiment, the busbar unit 26 is held by the partition wall 10 with the three-phase terminal 33 inserted into the through hole 51 of the partition wall 10 and the plate member 57 of the retaining member 56 attached to the partition wall 10. As a result, the position of the busbar unit 26 is fixed, and it can be stably attached to the partition wall 10.

[0053] In this embodiment, the retaining member 56 is configured to have a plate member 57 fixed to the inverter chamber 17 side of the partition wall 10, and a retaining ring 58 positioned between the plate member 57 and the O-ring 53 and fitted into the through hole 51. This makes it possible to prevent the O-ring 53 from coming off with a relatively simple configuration.

[0054] Furthermore, in this embodiment, a chamfered portion 54 is formed on the partition wall 10 at the opening edge of the through hole 51 on the inverter chamber 17 side, making it easier to insert the O-ring 53 into the through hole 51. In addition, since the anti-slip ring 58 is shaped to match the inclination of the chamfered portion 54, the O-ring 53 can be more reliably prevented from coming loose.

[0055] Next, Figures 10 and 11 show cross-sectional views of electric compressors 1 of other embodiments, corresponding to Figures 7 and 8 described above. Components indicated by the same reference numerals in each figure as those in Figures 7 and 8 are assumed to perform the same or similar functions.

[0056] In this embodiment, the anti-detachment ring 58 of the aforementioned retaining member 56 is shaped to match the gap between the end of the chamfered portion 54 of the partition wall 10 on the motor chamber 15 side and the small diameter portion 37B of the resin portion 37. This anti-detachment ring 58 also ensures that the O-ring 53 is not easily dislodged.

[0057] Next, Figures 12 and 13 show cross-sectional views of another embodiment of the electric compressor 1, corresponding to Figures 7 and 8 described above. Components in each figure that are given the same reference numerals as those in Figures 7 and 8 perform the same or similar functions.

[0058] In this embodiment, the aforementioned retaining member 56 does not have a retaining ring 58. Instead, a projection 62 is provided around the hole 61 of the plate member 57 that enters into the through hole 51, and this projection 62 is shaped to match the gap dimension between the end of the chamfered portion 54 on the motor chamber 15 side and the small diameter portion 37B of the resin portion 37.

[0059] This configuration makes it possible to more reliably prevent the O-ring 53 from coming off using the protrusion 62 of the plate member 57, without using a separate component such as the aforementioned anti-slip ring.

[0060] Next, Figures 14 and 15 show cross-sectional views of another embodiment of the electric compressor 1, corresponding to Figures 7 and 8 mentioned above. Components in each figure that are indicated by the same reference numerals as those in Figures 12 and 13 perform the same or similar functions.

[0061] In this embodiment as well, the aforementioned retaining member 56 does not have a retaining ring 58. Instead, a projection 62 is provided around the hole 61 of the plate member 57 that enters into the through hole 51, and this projection 62 is shaped to match the inclination of the chamfered portion 54.

[0062] Even with this configuration, it is possible to reliably prevent the O-ring 53 from coming off using the protrusion 62 of the plate member 57 without using separate components such as the aforementioned anti-slip ring.

[0063] Next, we will describe yet another embodiment of the electric compressor 1 with reference to Figures 16 to 20. Figure 16 is an enlarged view of the winding connection portion 41 of the electric compressor 1 in this embodiment, and Figures 17 to 19 illustrate the busbar unit 26, through hole 51, and sealing member 63 of this embodiment. In each figure, components indicated by the same reference numerals as in Figures 1 to 15 are considered to have the same or similar functions.

[0064] In this embodiment, as in the previously described embodiment, a keyway 31 is formed in the insulator 27 of the motor 4, and the claw portion 47 of the leg portion 43 of the busbar unit 26 enters the keyway 31, allowing it to move in the axial direction. However, the sealing structure of the through hole 51 portion is different.

[0065] In this embodiment, the lead portion 23A of the magnet wire 23 is connected to the winding connection portion 41 of the busbar unit 26 with a predetermined slack in its length. This slack is set to a length greater than the distance the busbar unit 26 is pulled towards the partition wall 10, as will be described later, and is assumed to be guided to bend in a certain direction before being pulled (left side of Figure 16).

[0066] Furthermore, in this embodiment, three terminal holding portions 37C are formed upright on the resin portion 37 of the busbar unit 26, and the three-phase terminals 33 protrude from each terminal holding portion 37C. Two bolt holes 64 are formed on the surface of the busbar unit 26 on the terminal holding portion 37C side, and bolt holes 66 and 67 are also formed in the sealing member (gasket) 63 and partition wall 10 at positions corresponding to each bolt hole 64. In addition, holes 68 are formed in the sealing member 63 at positions corresponding to each terminal holding portion 37C.

[0067] Next, the installation procedure for the busbar unit 26 in this embodiment will be described with reference to Figure 20. As described above, after the busbar unit 26 is installed on the insulator 27, the sealing member 63 is placed on the side of the busbar unit 26 facing the terminal holding portion 37C. At this time, each terminal holding portion 37C passes through the hole 68 of the sealing member 63. Also, at this time, the lead portion 23A of the magnet wire 23 is in the state shown on the left side of Figure 16.

[0068] In this state, the motor 4 is shrink-fitted into the casing 2. At this time, each three-phase terminal 33 corresponds to each through-hole 51, and the bolt holes 64 correspond to each bolt holes 66 and 67 (left side of Figure 20). In this state, two bolts 71 are inserted into the bolt holes 67 and 66 from the inverter room 17 side (center of Figure 20), and their ends are screwed into the bolt holes 64 of the busbar unit 26. By screwing in these bolts 71, the busbar unit 26 is pulled towards the bulkhead 10 side, and finally fixed to the motor room 15 side of the bulkhead 10 via the sealing member 63, as shown on the right side of Figure 20.

[0069] During this installation process, the lead portion 23A extends as shown on the right side of Figure 16 (the excess length extends), so the lead portion 23A will not come off the winding connection portion 41. Then, with the busbar unit 26 attached to the partition wall 10 as described above, each three-phase terminal 33 passes through each through hole 51, and its tip faces the inverter room 17.

[0070] In this manner, the lead portion 23A of the magnet wire 23 is connected to the winding connection portion 41 of the busbar unit 26 with a predetermined allowance in its length, and a bolt 71 that penetrates the bulkhead from the inverter room 17 side is screwed into the busbar unit 26, pulling the busbar unit 26 towards the bulkhead 10 side and fixing it to the motor room 15 side of the bulkhead 10. As a result, the three-phase terminal 33 is inserted into the through hole 51, passes through the through hole 51, and its tip faces the inverter room 17, so that the busbar unit 26 and the motor 4 can be attached to the casing 2 independently. Furthermore, the allowance in the lead portion 23A can absorb any misalignment between the busbar unit 26 and the motor 4, thereby improving the ease of installation of the busbar unit 26.

[0071] In this case, as in the embodiment, a keyway 31 is formed in the insulator 27 of the motor 4, and a claw portion 47 of the leg portion 43 that enters the keyway 31 is formed on the busbar unit 26, and by making this claw portion 47 movable in the axial direction within the keyway 31, the busbar unit 26 can be held by the motor 4 and pulled towards the partition wall 10 by screwing in the bolt 71.

[0072] Furthermore, by interposing a sealing member 63 between the partition wall 10 and the busbar unit 26, as in the embodiment, it becomes possible to ensure a seal between the motor room 15 and the inverter room 17.

[0073] Furthermore, in this embodiment, the slack provided in the lead portion 23A is set to a dimension greater than the distance by which the busbar unit 26 is pulled towards the bulkhead 10 by screwing in the bolt 71, so that the busbar unit 26 can be fixed to the bulkhead 10 without any problems.

[0074] Next, with reference to Figures 21 to 23, we will describe another embodiment of the electric compressor 1 shown in Figures 16 to 20. In this case, the busbar unit 26 has one terminal holding portion 37D, and three three-phase terminals 33 protrude from this terminal holding portion 37D. Therefore, there is only one hole 68 in the sealing member 63, and only one through-hole 51 in the partition wall 10. The rest is the same as in Figures 16 to 20. This configuration also produces the same effects as described above.

[0075] 1 Electric compressor 2 Casing 3 Scroll compression element 4 Motor 8 Rotating shaft 10 Partition wall 15 Motor room 16 Inverter 17 Inverter room 21 Stator 22 Core 23 Magnet wire 23A Lead section 24 Rotor 26 Busbar unit 25, 27 Insulator 29 Slot 31 Keyway 33 Three-phase terminal 36 Busbar 37 Resin part 41 Winding connection part 43 Leg part 47 Claw part 51 Through hole 53 O-ring 54 Chamfered part 56 Retaining member 57 Plate member 58 Anti-loosening ring 62 Protrusion 63 Seal member 71 Bolt

Claims

1. A motor comprising a stator having a core and an insulator provided on the core around which magnet wires are wound, and a busbar unit formed by molding busbars made of resin to electrically connect the magnet wires coming out of each slot of the stator to three-phase terminals, wherein the insulator or the outer circumference of the core has a keyway, and the busbar unit has legs formed thereon that enter the keyway, the width of the legs being smaller than the width of the keyway.

2. The motor according to claim 1, characterized in that the keyway is formed on the outer circumference of the insulator.

3. An electric compressor comprising a motor room containing a motor according to claim 1 or claim 2, an inverter room equipped with an inverter for supplying power to the motor, a partition wall separating the motor room and the inverter room, and a casing having through holes formed in the partition wall, wherein the busbar unit has a resin part for molding the three-phase terminals, the three-phase terminals protruding from the resin part, passing through the through holes from the motor room side, and their tips facing the inverter room.

4. The electric compressor according to claim 3, further comprising an O-ring for sealing the gap between the resin portion of the portion in which the three-phase terminal protrudes and the through hole in the partition wall, wherein the O-ring is inserted into the through hole from the inverter chamber side and held by the resin portion on the motor chamber side, and a retaining member for the O-ring is attached to the inverter chamber side of the partition wall.

5. The electric compressor according to claim 4, characterized in that the busbar unit is held by the partition wall with the three-phase terminals inserted into the through-holes of the partition wall and the retaining member attached to the partition wall.

6. A method for manufacturing an electric compressor comprising a motor chamber containing a motor, an inverter chamber equipped with an inverter for supplying power to the motor, a partition wall separating the motor chamber and the inverter chamber, and a casing having through holes formed in the partition wall, wherein the motor comprises a stator having a core and an insulator provided on the core around which magnet wires are wound, a busbar unit formed by molding busbars out of resin to electrically connect the magnet wires coming out of each slot of the stator to three-phase terminals, a keyway formed on the outer circumference of the insulator or the core, and legs formed on the busbar unit that enter the keyway, the busbar unit having a resin part for molding the three-phase terminals, the three-phase terminals protruding from the resin part, the width of the legs of the busbar unit being smaller than the width of the keyway, and inserting the three-phase terminals into the through holes from the motor chamber side, passing through the through holes, and bringing the tips of the three-phase terminals toward the inverter chamber.

7. The method for manufacturing an electric compressor according to claim 6, characterized in that an O-ring for sealing the gap between the resin portion of the portion in which the three-phase terminal protrudes and the through hole in the partition wall is inserted into the through hole from the inverter chamber side, the motor chamber side is held in place by the resin portion, and a retaining member for the O-ring is attached to the inverter chamber side of the partition wall, and the busbar unit is held in place by the partition wall in that state.

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