JP7294124B2 - electric compressor - Google Patents

Description

The present invention relates to electric compressors.

Patent Document 1 discloses a conventional electric compressor. This electric compressor includes a housing, a drive shaft, a motor mechanism, and a compression mechanism. The drive shaft, motor mechanism and compression mechanism are all provided within the housing. The drive shaft is rotatable about the drive shaft within the housing. The motor mechanism rotates the drive shaft around the drive axis. The compression mechanism is driven by the drive shaft and compresses the refrigerant as a fluid.

More specifically, the motor mechanism has a stator and a rotor. A stator is secured within the housing. A drive shaft is fixed to the rotor. The rotor is arranged in the stator and is rotatable around the drive shaft together with the drive shaft. The rotor has a rotor body, a plurality of permanent magnets, and a pair of plates. The rotor body is made of a plurality of steel plates laminated in the direction of the drive shaft. Each permanent magnet is provided on the rotor body. Each plate is thicker than each steel plate. Each plate sandwiches the rotor body in the direction of the drive axis.

Further, each steel plate and each plate are formed with an insertion hole and a plurality of communication holes. A drive shaft is inserted through the insertion hole. Each communication hole is positioned on the outer peripheral side of the insertion hole and arranged in the circumferential direction of the insertion hole.

In this electric compressor, the drive shaft is fixed to the rotor main body and thus to the rotor by being fitted into the insertion holes formed in the respective steel plates. Also, although there is no specific description in the document, the rotor body and each plate are generally fastened with fasteners.

In this electric compressor, the rotor, and thus the motor mechanism, rotates the drive shaft around the drive shaft in the housing. This activates the compression mechanism to compress the refrigerant.

JP 2013-90479 A

In the above-described conventional electric compressor, the rotor body, that is, each steel plate, is constrained in the drive shaft direction by the plates, and pressed in the drive shaft direction by sandwiching the rotor body in the drive shaft direction. be done. Here, each steel plate is thinner than each plate. As a result, the insertion hole formed in each steel plate can be deformed so as to extend in the radial direction due to the load when each steel plate is pressed in the drive shaft center direction. In particular, in a structure in which each plate and the rotor body are fastened with a fastener, the periphery of the fastener is locally strongly pressed, so in each steel plate, the inner peripheral surface of the insertion hole may locally protrude inward. It will be. In this case, in this electric compressor, the portion protruding inward on the inner peripheral surface of the insertion hole interferes with the drive shaft, so that the drive shaft can be suitably fitted into the insertion hole formed in each steel plate. The problem arises that the drive shaft cannot be suitably fixed to the rotor.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electric compressor capable of suitably fixing a drive shaft to a rotor.

The electric compressor of the present invention includes a housing,
a drive shaft provided within the housing and rotatable about a drive axis;
a motor mechanism provided in the housing for rotating the drive shaft;
An electric compressor comprising a compression mechanism provided in the housing and driven by the drive shaft to compress a fluid,
The motor mechanism has an annular stator fixed within the housing and a rotor disposed within the stator,
The rotor includes a rotor body made of a plurality of steel plates laminated in the drive shaft center direction, a plurality of permanent magnets provided in the rotor body, and a wall thickness greater than that of each of the steel plates. a pair of plates sandwiched in the direction of the drive axis; and a plurality of fasteners for fastening the rotor body and the plates in the direction of the drive axis,
Each of the steel plates and each of the plates includes an insertion hole through which the drive shaft is inserted, a plurality of communication holes positioned on the outer peripheral side of the insertion hole and arranged in the circumferential direction of the insertion hole, and a circumference of the insertion hole. a fastening hole through which the fastener is inserted and positioned between the communicating holes adjacent in the direction, and a fastening hole not positioned between the communicating holes adjacent in the circumferential direction of the insertion hole and through which the fastener is inserted. A fastening hole through which the fastener other than the fastener inserted in the fastening hole positioned between the communicating holes adjacent in the circumferential direction of the hole is inserted is formed,
The drive shaft is fitted into the through hole formed in each steel plate,
A notch is formed in each of the plates so as to allow communication between the through hole formed in each of the plates and the communication hole and to face the rotor main body.

In the electric compressor of the present invention, the rotor body is composed of a plurality of steel plates laminated in the drive shaft center direction, and each steel plate is thinner than each plate. In this electric compressor, the rotor body is held between the pair of plates in the drive axis direction, and the rotor body and the plates are fastened together in the drive axis direction by fasteners. Here, in this electric compressor, a notch is formed in each plate, and this notch communicates the insertion hole and the communication hole formed in each plate, and faces the rotor main body.

In addition, the restraining force on the rotor body in the direction of the drive shaft is reduced at the portions where the notches exist in each plate. Thus, in this electric compressor, when the rotor body and each plate are fastened together in the drive axis direction by the fastener, each steel plate is easily deformed in the drive axis direction toward the notch side. As a result, in each steel plate, that is, in the rotor body, the inner peripheral surface of the insertion hole is less likely to locally protrude inward. can be made

Therefore, according to the electric compressor of the present invention, the drive shaft can be preferably fixed to the rotor.

Here, in the present invention, the position of the notch provided in each plate is the position between the through hole and the communicating hole that have already been formed through. Since this portion has relatively lower rigidity than other portions in each plate, the effect of providing the notch on the rigidity of each plate as a whole is small. Therefore, in this electric compressor, the drive shaft can be suitably fitted into the insertion hole formed in each steel plate without substantially reducing the rigidity of the rotor as a whole.

The notch preferably extends through each plate in the direction of the drive axis. In this case, the notches can be formed at the same time as the through holes and communication holes are formed in each plate, which facilitates the processing of each plate. Therefore, with this electric compressor, the productivity is improved, and the manufacturing cost can be reduced. In addition, since the notches pass through the plates in the direction of the drive shaft, when the rotor main body and the plates are fastened in the direction of the drive shaft, the steel plates move toward the notches. Since it becomes easier to deform in the center direction, it becomes more difficult for the insertion holes formed in each steel plate to deform in the radial direction.

According to the electric compressor of the present invention, the drive shaft can be preferably fixed to the rotor.

FIG. 1 is a schematic diagram showing an electric compressor of an embodiment. FIG. 2 is an enlarged cross-sectional view of the main part showing the X portion of FIG. 1, relating to the electric compressor of the embodiment. FIG. 3 relates to the electric compressor of the embodiment, and is a front view of a rotor body and permanent magnets as seen from the front side. FIG. 4 is a front view of the first plate viewed from the front side in the electric compressor of the embodiment. FIG. 5 is a rear view of the second plate viewed from the rear side, relating to the electric compressor of the embodiment. FIG. 6 is a front view of the rotor viewed from the front side, relating to the electric compressor of the embodiment. FIG. 7 is a front view of the electric compressor of the embodiment, as seen from the front side, showing a state in which the drive shaft is fixed to the rotor. FIG. 8 is a front view of the rotor of the electric compressor of the comparative example as seen from the front side. FIG. 9 relates to an electric compressor of a comparative example, and is a front view of a rotor body and permanent magnets as seen from the front side, showing deformation of a specific region due to heating.

Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. Specifically, the electric compressor of the embodiment is a scroll type electric compressor. This electric compressor is mounted on a vehicle (not shown) and constitutes a refrigeration circuit of the vehicle.

As shown in FIG. 1, the electric compressor of the embodiment includes a housing 1, a drive shaft 3, a motor mechanism 5, and a compression mechanism 7. As shown in FIG. The housing 1 has a housing body 11 , a first cover 13 and a second cover 15 .

In this embodiment, the solid-line arrows shown in FIG. 1 define the longitudinal direction and the vertical direction of the electric compressor. 2 onward, corresponding to FIG. 1, the front-rear direction and the vertical direction of the electric compressor are defined. It should be noted that each of these directions is an example for convenience of explanation, and the posture of the electric compressor is appropriately changed according to the vehicle or the like in which it is mounted.

As shown in FIG. 2, the housing body 11 has a front wall 11a and a peripheral wall 11b. The front wall 11 a is located at the front end of the housing body 11 and extends in the radial direction of the housing body 11 . The peripheral wall 11b is connected to the front wall 11a and extends rearward in the direction of the drive axis O of the drive shaft 3 from the front wall 11a. The front wall 11a and the peripheral wall 11b form a substantially cylindrical housing body 11 extending in the drive axis O direction. Here, the direction of the drive axis O is parallel to the longitudinal direction of the electric compressor. Thus, the housing body 11 has a bottomed cylindrical shape extending in the direction of the drive axis O, that is, in the front-rear direction of the electric compressor.

Further, the housing body 11 is formed with a suction port 11c and a plurality of bolt holes 11d. Furthermore, a motor chamber 111 is formed inside the housing body 11 .

The suction port 11 c extends in the radial direction of the housing body 11 and communicates the outside of the housing body 11 with the motor chamber 111 . In addition, the suction port 11c is connected to an evaporator (not shown) via a pipe (not shown). As a result, the low-temperature, low-pressure refrigerant gas that has passed through the evaporator is sucked into the motor chamber 111 . Refrigerant gas is an example of "fluid" in the present invention. That is, the motor chamber 111 also functions as a suction chamber. As shown in FIG. 1 , each bolt hole 11 d extends in the direction of the drive axis O and opens at the rear end of the housing body 11 . Note that FIG. 1 illustrates one of the plurality of bolt holes 11d.

The first cover 13 is positioned on the front side of the housing body 11 in the direction of the drive axis O. As shown in FIG. The first cover 13 is fixed to the front wall 11a of the housing body 11 with a plurality of bolts (not shown). The first cover 13 is formed in a cylindrical shape with a bottom, and accommodates an inverter circuit (not shown) inside.

The second cover 15 is located on the rear side of the housing body 11 in the direction of the drive axis O. As shown in FIG. The second cover 15 is fixed to the rear end of the housing body 11 with a plurality of bolts 15a. Note that FIG. 1 illustrates one of the plurality of bolts 15a. The second cover 15 is formed in a cylindrical shape with a bottom, and a discharge chamber (not shown) is formed inside. The discharge chamber is connected to a condenser (not shown) by a pipe (not shown).

As shown in FIGS. 1 and 2 , the drive shaft 3 is provided inside the housing body 11 including the inside of the motor chamber 111 . As shown in FIG. 2, the drive shaft 3 has a cylindrical shape extending in the direction of the drive axis O, and has a small diameter portion 3a, a large diameter portion 3b, and a tapered portion 3c. The small diameter portion 3 a is located on the front end side of the drive shaft 3 . The large diameter portion 3b is located on the rear side of the small diameter portion 3a. The large diameter portion 3b is formed to have a larger diameter than the small diameter portion 3a. The tapered portion 3c is located between the small diameter portion 3a and the large diameter portion 3b. The tapered portion 3c is connected at its front end to the small diameter portion 3a. The tapered portion 3c is connected to the large-diameter portion 3b at its rear end while increasing in diameter toward the rear.

The drive shaft 3 is rotatably supported by the front wall 11 a of the housing body 11 via a radial bearing 19 at the small diameter portion 3 a. As a result, the drive shaft 3 is rotatable around the drive axis O within the motor chamber 111 .

The motor mechanism 5 is provided inside the motor chamber 111 . The motor mechanism 5 has a stator 5a and a rotor 5b. The stator 5 a is fixed to the inner peripheral surface of the peripheral wall 11 b inside the motor chamber 111 . The stator 5a is connected with an inverter circuit.

The stator 5 a has a stator core 501 and coil ends 503 . Stator core 501 is formed in a cylindrical shape. A coil 505 is wound around the stator core 501 . The coil end 503 has an annular shape that protrudes forward and backward in the direction of the drive axis O from the stator core 501 .

The rotor 5b is arranged inside the stator 5a. The rotor 5 b has a rotor body 51 , multiple magnet cores 52 , a first plate 53 , a second plate 54 , a rotor weight 55 and multiple fastening pins 56 . Each magnet core 52 is an example of a "permanent magnet" in the present invention. Also, the first plate 53 and the second plate 54 are examples of "plates" in the present invention.

The rotor body 51 is formed of a plurality of electromagnetic steel plates 510 having the same shape. Each electromagnetic steel sheet 510 is an example of a "steel sheet" in the present invention. As shown in FIG. 3, each electromagnetic steel plate 510 is formed in a disc shape. A fixing hole 51 a is formed at the center of each electromagnetic steel plate 510 , that is, at the center of the rotor body 51 . Further, in each electromagnetic steel plate 510, five through holes 51b are formed on the outer peripheral side of the fixing hole 51a. Furthermore, in each electromagnetic steel plate 510, first pin holes 555 to 558 and ten accommodation holes 51c are formed on the outer peripheral side of each through hole 51b. The fixing hole 51a, the through holes 51b, the first pin holes 555 to 558, and the receiving holes 51c penetrate the electromagnetic steel plate 510 in the drive axis O direction. Here, the fixing holes 51a, the through holes 51b, the first pin holes 51c, and the receiving holes 51c are separated from each other and do not communicate with each other.

The fixing hole 51 a is formed as a round hole aligned with the large diameter portion 3 b of the drive shaft 3 . More strictly, the fixing hole 51a is formed in a round hole having a diameter slightly smaller than that of the large diameter portion 3b. Each through hole 51b is formed in a substantially fan shape, and is arranged at equal intervals in the circumferential direction of the fixing hole 51a. Each of the first pin holes 555 to 558 is formed as a circular hole and arranged in the circumferential direction of the fixed hole 51a on the outer peripheral side of each through hole 51b. Here, among the first pin holes 555 to 558, the first pin hole 555 and the first pin hole 556 are adjacent to each other in the circumferential direction of the fixed hole 51a and are located on the outer peripheral side of each through hole 51b. 51b. On the other hand, although the first pin holes 557 and 558 are located on the outer peripheral side of each through hole 51b, they are not arranged between the through holes 51b adjacent in the circumferential direction of the fixed hole 51a. do not have. Accordingly, the fixing hole 51a, the through holes 51b, and the first pin holes 555 and 556 are examples of the "insertion hole", the "through hole", and the "fastening hole" in the present invention, respectively. More specifically, the fixing hole 51a, the through holes 51b, and the first pin holes 555 and 556 are defined as "insertion holes formed in each steel plate,""through holes formed in each steel plate," and "through holes formed in each steel plate." It is an example of "a formed fastening hole". Each accommodation hole 51c is formed in a rectangular shape, and is arranged in the circumferential direction of the fixing hole 51a on the outer peripheral side of each through hole 51b. The shape and number of the through holes 51b, the first pin holes 555 to 558, and the receiving holes 51c can be appropriately designed .

As shown in FIG. 2, each electromagnetic steel plate 510 is laminated on each other in the drive axis O direction. At this time, the electromagnetic steel plates 510 are arranged so that the fixing holes 51a are aligned in the direction of the drive axis O, and the through holes 51b, the first pin holes 555 to 558, and the accommodation holes 51c are aligned with the drive axis. They are aligned in the O direction. Thus, the rotor body 51 is formed. That is, in the rotor main body 51, the fixing hole 51a, the through holes 51b, the first pin holes 555 to 558, and the receiving holes 51c penetrate in the drive axis O direction. Thereby, the rotor main body 51 forms a substantially cylindrical body extending in the direction of the drive axis O. As shown in FIG. In addition to the plate thickness of each magnetic steel plate 510, the number of each magnetic steel plate 510 is simplified and illustrated in FIG. 2 for ease of explanation.

Further, by forming the fixing holes 51a and the through holes 51b, as shown in FIG. The location is designated as a specific area 511 . On the other hand, in the rotor main body 51, a portion located on the outer peripheral side of the through holes 51b is an outer peripheral region 512. As shown in FIG. That is, the first pin holes 555 to 558 and the receiving holes 51c are arranged in the outer peripheral area 512. As shown in FIG. Further, in the rotor main body 51, portions between the through-holes 51b are connected portions 513, respectively. Each connecting portion 513 is connected to the specific area 511 and the outer peripheral area 512 . That is, in the rotor main body 51, the specific region 511 and the outer peripheral region 512 form a substantially cylindrical body with the through holes 51b and the connecting portions 513 existing therebetween. Here, the thickness of the specific region 511 in the radial direction of the rotor body 51 is thinner than the thickness of the outer peripheral region 512 in the radial direction of the rotor body 51 .

As shown in FIGS. 2 and 3, each magnet core 52 is formed in a rectangular columnar shape extending in the drive axis O direction. The length of each magnet core 52 in the direction of the drive axis O is substantially the same as the length of the rotor body 51 in the direction of the drive axis O. As shown in FIG. Each magnet core 52 is housed in each housing hole 51c. Thereby, as shown in FIG. 3, each magnet core 52 is arranged in the circumferential direction of the fixing hole 51a in the outer peripheral region 512 of the rotor body 51. As shown in FIG.

As shown in FIG. 2 , the first plate 53 is positioned forward of the rotor body 51 in the direction of the drive axis O. As shown in FIG. The first plate 53 is formed of a disk-shaped metal plate. More specifically, the first plate 53 is made of a plate material that is thicker in the drive axis O direction than each of the electromagnetic steel plates 510 . That is, the first plate 53 is thicker than each electromagnetic steel plate 510 . Further, as shown in FIGS. 6 and 7, the first plate 53 has a disk shape with a smaller diameter than each electromagnetic steel plate 510, that is, the rotor body 51. As shown in FIG.

As shown in FIG. 4, a first insertion hole 53a is formed in the center of the first plate 53. As shown in FIG. Further, in the first plate 53, five first communication holes 53b are formed on the outer peripheral side of the first insertion hole 53a. Further, in the first plate 53, second pin holes 535 to 538 are formed on the outer peripheral side of each first communicating hole 53b. The first insertion hole 53a, the first communication hole 53b, and the second pin holes 535 to 538 penetrate the first plate 53 in the direction of the drive axis O, respectively. Here, the first communication hole 53b and the second pin holes 535 to 538 are separated from each other and do not communicate with each other.

The first insertion hole 53a is formed as a round hole. More precisely, as shown in FIGS. 2 and 7, the first insertion hole 53a is formed in a circular shape having a larger diameter than the fixing hole 51a of the rotor body 51 and the large diameter portion 3b of the drive shaft 3. ing. The first communication holes 53b are formed in a substantially fan shape that matches the through holes 51b of the rotor body 51, and are arranged at equal intervals in the circumferential direction of the first insertion holes 53a. The second pin holes 535 to 538 are circular holes aligned with the first pin holes 555 to 558 of the rotor body 51, and arranged in the circumferential direction of the first insertion hole 53a. Here, of the second pin holes 535 to 538, the second pin hole 535 and the second pin hole 536 are located on the outer peripheral side of each first communication hole 53b and are adjacent in the circumferential direction of the first insertion hole 53a. It is arranged between the matching first communication holes 53b. On the other hand, the second pin hole 537 and the second pin hole 538 are located on the outer peripheral side of each first communication hole 53b, but are located between the first communication holes 53b adjacent in the circumferential direction of the first insertion hole 53a. not placed in between. Accordingly, the first insertion hole 53a, the first communication holes 53b, and the second pin holes 535 and 536 are examples of the "insertion hole", the "through hole", and the "fastening hole" in the present invention, respectively. More specifically, the first insertion hole 53a, each first communication hole 53b, and each second pin hole 535, 536 are defined as "the insertion hole formed in each plate", "the through hole formed in each plate", and It is an example of "a fastening hole formed in each plate . "

Moreover, as shown in FIG. 4, the first plate 53 has a first restricting portion 53d, a first outer peripheral portion 53e, and five first through holes 53a and first communication holes 53b. 1 bridge portion 53f is formed. The first restricting portion 53d is positioned between the first insertion hole 53a and each first communication hole 53b. The first outer peripheral portion 53e is located on the outer peripheral side of each first communication hole 53b. Each first bridge portion 53f is located between each first communication hole 53b. Each first bridge portion 53f is connected to the first restraint portion 53d and the first outer peripheral portion 53e.

Further, the first plate 53 is formed with five first notches 53g. 53 g of each 1st notch is an example of the "notch" in this invention. Each first notch 53g is located between the first insertion hole 53a and each first communication hole 53b. Each first notch 53g extends in the radial direction of the first plate 53 and connects to the first insertion hole 53a and each first communication hole 53b. Further, each first notch 53g penetrates the first plate 53 in the drive axis O direction. Accordingly, in the first plate 53, the first restraining portions 53d are cut out in the radial direction of the first plate 53 by the first notches 53g. That is, the first restraining portion 53d is divided into five pieces by each first notch 53g.

As shown in FIG. 2, the second plate 54 is located on the rear side of the rotor body 51 in the direction of the drive axis O. As shown in FIG. As with the first plate 53 , the second plate 54 is also formed of a plate material having a greater thickness in the drive axis O direction than each of the electromagnetic steel plates 510 . The second plate 54 also has a disc shape with a smaller diameter than each electromagnetic steel plate 510 , that is, the rotor body 51 .

As shown in FIG. 5, the second plate 54 is formed with a second insertion hole 54a, five second communication holes 54b, and third pin holes 545-548. Of the third pin holes 545 to 548, the third pin hole 545 and the third pin hole 546 are adjacent to each other in the circumferential direction of the second insertion hole 54a on the outer peripheral side of each second communication hole 54b. It is arranged between the two communication holes 54b. On the other hand, although the third pin hole 547 and the third pin hole 548 are located on the outer peripheral side of each of the second communication holes 54b, they are located between the second communication holes 54b adjacent in the circumferential direction of the second insertion holes 54a. not placed in between. Further, the second plate 54 is formed with a second restraint portion 54d, a second outer peripheral portion 54e, and five second bridge portions 54f. Further, in the second plate 54, second cutouts 54g are formed between the second insertion holes 54a and the respective second communication holes 54b. The second insertion hole 54a, the second communication holes 54b, and the third pin holes 545 and 546 are also defined as "through holes formed in each plate", "through holes formed in each plate", and "through holes formed in each plate" in the present invention, respectively. It is an example of "a fastening hole formed in each plate." Each second notch 54g is also an example of a "notch" in the present invention. The configuration of the second plate 54 is the same as that of the first plate 53, including the configuration of the second insertion hole 54a and the like, so detailed description thereof will be omitted. That is, in the second plate 54 as well, the second restraining portions 54d are cut out in the radial direction of the second plate 54 by the respective second cutouts 54g. Therefore, the second restraining portion 54d is also divided into five pieces by the second notches 54g .

As shown in FIG. 4, the rotor weight 55 is formed of a substantially arc-shaped metal plate. As shown in FIG. 2, the rotor weight 55 is thicker than the first and second plates 53 and 54 . Further, as shown in FIG. 4, the rotor weight 55 is formed with a fourth pin hole 55a. Each of the fourth pin holes 55a and 55b is formed as a round hole aligned with the second pin holes 537 and 538 of the first plate 53, and passes through the rotor weight 55 in the drive axis O direction. The shape and plate thickness of the rotor weight 55 can be appropriately designed.

As shown in FIG. 2, in the rotor 5b, a rotor weight 55, a first plate 53, a rotor main body 51, and a second plate 54 are arranged in this order from the front side in the direction of the drive axis O. Each magnet core 52 is already provided in the rotor main body 51 . In the rotor 5b, the fixing hole 51a of the rotor main body 51 and the first and second insertion holes 53a and 54a of the first and second plates 53 and 54 are aligned in the direction of the drive axis O, and each of the rotor main bodies 51 is aligned. The through hole 51b and the first and second communication holes 53b and 54b of the first and second plates 53 and 54 are aligned in the drive axis O direction. Further, in the rotor 5b, the first pin holes 555 to 558 of the rotor main body 51, the second and third pin holes 535 to 538 and 545 to 548 of the first and second plates 53 and 54, and the rotor weight 55 The fourth pin holes 55a and 55b are aligned in the drive axis O direction. In this state, as shown in FIG. 6, each fastening pin 56 extends in the direction of the drive shaft center O with respect to each of the first to fourth pin holes 555 to 558, 535 to 538, 545 to 548, 55a, and 55b. The front and rear ends of each connecting pin 56 are crimped.

Thus, in the rotor 5b, the rotor main body 51, the first and second plates 53 and 54, and the rotor weight 55 are fastened together in the direction of the drive axis O and integrated. That is, in the rotor 5b, the rotor main body 51 is sandwiched between the first and second plates 53 and 54 from both sides in the drive axis O direction. These prevent the electromagnetic steel plates 510 forming the rotor body 51 from being separated from each other in the rotor 5b.

Further, the rotor main body 51 is sandwiched between the first and second plates 53 and 54 from both sides in the drive axis O direction, so that the fixing hole 51a and the first and second insertion holes 53a and 54a are aligned in the drive axis O direction. are in communication with each other. Further, each through hole 51b and each of the first and second communication holes 53b and 54b are also in communication with each other in the drive axis O direction. Here, the through holes 51b and the first and second communication holes 53b and 54b are blocked by the rotor weight 55 on the first plate 53 side, that is, on the front side in the direction of the drive axis O. .

As shown in FIG. 6, in the rotor 5b, the first restraining portion 53d of the first plate 53 is in surface contact with the specific region 511 of the rotor body 51 from the front side in the drive axis O direction. Similarly, the second restraint portion 54d of the second plate 54 is in surface contact with the specific region 511 from the rear side in the direction of the drive axis O (see FIG. 2). As a result, the specific region 511 and thus the rotor body 51 are restrained in the direction of the drive axis O by the first restraining portion 53d and the second restraining portion 54d. On the other hand, as shown in FIG. 6, each first notch 53g of the first plate 53 is out of contact with the specific region 511. As shown in FIG. Although detailed illustration is omitted, each of the second notches 54g of the second plate 54 is similarly not in contact with the specific region 511. As shown in FIG. That is, the specific region 511 is out of contact with the first plate 53 and the second plate 54 at the locations where the first and second notches 53g and 54g are present, and is not constrained in the direction of the drive axis O. .

Also, the first outer peripheral portion 53e of the first plate 53 and the second outer peripheral portion 54e of the second plate 54 are in surface contact with the outer peripheral region 512 of the rotor body 51 from both sides in the drive axis O direction. Accordingly, each magnet core 52 provided in the rotor main body 51 faces the first and second plates 53 and 54, more specifically, the first and second outer peripheral portions 53e and 54e in the direction of the drive axis O. there is In this way, the first and second outer peripheral portions 53e and 54e prevent the magnet cores 52 from falling out of the receiving holes 51c in the direction of the drive axis O. As shown in FIG. Further, the first bridge portions 53f of the first plate 53 and the second bridge portions 54f of the second plate 54 are in surface contact with the connection portions 513 of the rotor body 51 from the front-rear direction.

As shown in FIGS. 2 and 7, the drive shaft 3 is fitted to the rotor 5b, more specifically, shrink-fitted and fixed. When the drive shaft 3 is shrink-fitted to the rotor 5b, the rotor 5b is induction-heated. Specifically, the periphery of the fixing hole 51a, that is, the first and second restraining portions 53d and 54d including the specific region 511 are heated by induction heating, and the diameter of the fixing hole 51a is expanded by thermal expansion. Then, in this state, the large-diameter portion 3b is inserted in the drive axis O direction through the fixing hole 51a and the first and second insertion holes 53a and 54a. In this way, the drive shaft 3 is fixed to the rotor 5b by shrink-fitting the large-diameter portion 3b into the fixing hole 51a. As a result, the rotor 5b and the drive shaft 3 are integrated so that they can rotate about the drive axis O as one. Since the first and second insertion holes 53a and 54a are formed to have a larger diameter than the large diameter portion 3b, only the large diameter portion 3b is inserted through the first and second insertion holes 53a and 54a. , and the large-diameter portion 3b is not fixed.

A known scroll-type compression mechanism is employed as the compression mechanism 7 shown in FIG. The compression mechanism 7 is arranged inside the housing body 11 so as to face a fixed scroll fixed to the inner peripheral surface of the peripheral wall 11 b on the rear side of the motor chamber 111 , and is rotatable and movable by the drive shaft 3 . Scroll and have. The fixed scroll and the movable scroll are meshed to form a compression chamber therebetween. Illustrations of the fixed scroll, the movable scroll, and the compression chamber are omitted.

In the electric compressor constructed as described above, the low-temperature, low-pressure refrigerant gas that has passed through the evaporator is sucked into the motor chamber 111 through the suction port 11c, as indicated by the dashed arrow in FIG. Further, power is supplied to the motor mechanism 5 by the inverter circuit. As a result, the rotor 5b rotates together with the drive shaft 3 around the drive axis O, and the compression mechanism 7 operates. Refrigerant gas sucked into the motor chamber 111 flows from the first plate 53 side through the first communication holes 53b, the through holes 51b, and the second communication holes 54b, and flows through the compression mechanism 7. introduced into That is, in this electric compressor, each through hole 51b and each of the first and second communication holes 53b and 54b function as introduction passages for introducing the refrigerant gas into the compression mechanism 7. As shown in FIG. Thus, the refrigerant gas introduced into the compression mechanism 7 is compressed in the compression chamber and discharged from the discharge chamber through the discharge port to the condenser.

Further, in this electric compressor, the stator 5a and the rotor 5b can be cooled by the refrigerant gas in the motor chamber 111. As shown in FIG. Furthermore, in this electric compressor, the rotor 5b can also be suitably cooled by the refrigerant gas flowing through the through holes 51b and the first and second communication holes 53b and 54b. In addition, since each through hole 51b and each of the first and second communication holes 53b and 54b function as introduction passages, it is not necessary to separately provide an introduction passage in the housing body 11. FIG.

Here, in this electric compressor, in the rotor 5b, the rotor main body 51 and the first and second plates 53 and 54 are displaced from each other, so that the magnet cores 52 are dropped from the rotor main body 51, or the rotor main body 51 is formed. It is required that the electromagnetic steel plates 510 are not separated from each other in the drive axis O direction. Therefore, in this electric compressor, it is necessary to firmly fasten the rotor main body 51 and the first and second plates 53 and 54 in the direction of the drive axis O using the connecting pins 56 . Therefore, in the rotor body 51, that is, in the electromagnetic steel plates 510 and the first and second plates 53 and 54, the periphery of each connecting pin 56 is strongly pressed locally. In this regard, in this electric compressor, even if each electromagnetic steel plate 510 is thinner than the first and second plates 53 and 54, each connecting pin 56 allows the rotor main body 51 and the first and second plates 53 and 54 to be connected. is fastened in the direction of the drive axis O, the inner peripheral surface of the fixing hole 51a is less likely to locally protrude inward. This action and effect will be specifically described based on a comparison with a comparative example.

As shown in FIG. 8, in the electric compressor of the comparative example, the first notch 53g is not formed between the first insertion hole 53a and the first communication holes 53b in the first plate 53 of the rotor 5b. . Although not shown, the second notch 54g is not formed between the second insertion hole 54a and the second communication holes 54b in the second plate 54 as well.

As a result, in the electric compressor of the comparative example, the first and second restraining portions 53d and 54d are not divided, and each of the first and second restraining portions 53d and 54d has a substantially annular shape. These first and second restraining portions 53 d and 54 d are in surface contact with the specific region 511 . Thus, in the electric compressor of the comparative example, substantially the entire specific region 511 is restrained from both sides in the drive axis O direction by the first and second restraining portions 53d and 54d. Other configurations of the electric compressor of the comparative example, including other configurations of the rotor 5b, are the same as those of the electric compressor of the embodiment. do.

In the electric compressor of the comparative example, the rotor main body 51 and the first and second plates 53 and 54 are fastened in the direction of the drive axis O by the connecting pins 56, so that the rotor main body 51, that is, the electromagnetic steel plates 510 are driven. It is pressed in the axial center O direction. Here, each electromagnetic steel plate 510 is thinner than the first and second plates 53 and 54 . Further, substantially the entire specific region 511 is restrained from both sides in the drive axis O direction by the first and second restraining portions 53d and 54d. Accordingly, in the electric compressor of the comparative example, each electromagnetic steel plate 510 including the specific region 511 cannot be deformed in the drive shaft center direction. That is, each electromagnetic steel sheet 510 cannot escape the deformation accompanying the load when pressed in the direction of the drive axis O in the direction of the drive axis O. Therefore, as shown in FIG. 9, the fixing hole 51a is deformed to extend in the radial direction by the load when each electromagnetic steel plate 510 is pressed in the direction of the drive axis O. As shown in FIG. Specifically, the first pin hole 555 and the first pin hole 556 are part of the electromagnetic steel sheet 510 in the radial direction of the electromagnetic steel sheet 510 toward the drive axis O without the through hole 51b interposed therebetween, that is, A connecting portion 513 exists in a spoke shape up to the fixing hole 51a. As a result, the strain deformation due to the pressing force acting locally around the first pin holes 555 and 556 propagates through the spoke-shaped region of the connection portion 513, that is, the electromagnetic steel plate 510, and the fixing holes 51a Appears as a local protrusion around.

As a result, in the electric compressor of the comparative example, the inner peripheral surface of the fixing hole 51a tends to locally protrude inward. Here, in the electric compressor of the comparative example, since the first and second restraining portions 53d and 54d are heated by induction heating, the above-described deformation of the fixing hole 51a becomes more pronounced. For these reasons, in the electric compressor of the comparative example, the large diameter portion 3b of the drive shaft 3 cannot be suitably fitted into the fixing hole 51a, and the drive shaft 3 cannot be suitably fixed to the rotor 5b.

On the other hand, in the electric compressor of the embodiment, as shown in FIGS. Notches 53g and 54g are formed respectively. In the electric compressor of the embodiment, as shown in FIGS. 2, 6 and 7, the first and second restraining portions 53d and 54d contact the specific region 511 to move the specific region 511 in the direction of the drive axis O. The first and second cutouts 53g and 54g are not in contact with the specific region 511 while being restrained from both sides. Accordingly, the first and second notches 53g and 54g do not constrain the specific region 511 in the drive axis O direction. Therefore, in the electric compressor of the embodiment, the contact areas of the first and second restraining portions 53d and 54d with respect to the specific region 511 are reduced by the presence of the first and second notches 53g and 54g. In particular, in the electric compressor of the embodiment, five first and second notches 53g and 54g are formed in the first and second plates 53 and 54, respectively. Therefore, the contact area of the specific region 511 with the first restraining portion 53d as a whole is sufficiently small, and the contact area of the specific region 511 with the second restraining portion 54d as a whole is sufficiently small. As a result, in the electric compressor of the embodiment, when the rotor main body 51 and the first and second plates 53 and 54 are fastened together by the connecting pins 56 in the direction of the drive axis O, The restraint in the direction of the drive axis O to the specific region 511 by 54d is reduced.

Thus, in the electric compressor of the embodiment, when the rotor main body 51 and the first and second plates 53 and 54 are fastened by the connecting pins 56 in the direction of the drive axis O, each electromagnetic steel plate 510 is connected to the first cutting edge. It becomes easier to deform in the direction of the drive axis O toward the notch 53g side or the second notch 54g side. In other words, each electromagnetic steel plate 510 can release deformation accompanying a load in the drive axis O direction when pressed in the drive axis O direction. Here, in the electric compressor of the embodiment as well, the first and second restraining portions 53d and 54d are heated by induction heating. It becomes easier to deform in the direction of the drive axis O toward the side. Therefore, as shown in FIG. 6, in the electric compressor of the embodiment, the inner peripheral surface of the fixing hole 51a is suppressed from locally protruding inward. As a result, as shown in FIG. 7, in the electric compressor of the embodiment, it is possible to suitably fit the large-diameter portion 3b into the fixing hole 51a.

Therefore, according to the electric compressor of the embodiment, the drive shaft 3 can be preferably fixed to the rotor 5b.

In particular, in this electric compressor, the first and second notches 53g and 54g respectively penetrate the first and second plates 53 and 54 in the drive axis O direction. Therefore, in this electric compressor, the first and second plates 53 and 54 are provided with first and second insertion holes 53a and 54a, first and second communication holes 53b and 54b, and second and third pin holes 535 to 538. When forming 545 to 548, it is possible to form the first and second notches 53g and 54g at the same time. Further, for example, recessed grooves are formed in the first and second plates 53 and 54 to communicate the first and second insertion holes 53a and 54a with the first and second communication holes 53b and 54b, respectively. are made into the first and second notches 53g and 54g, the processing of the first and second plates 53 and 54 is also facilitated. Therefore, the electric compressor has high productivity, and the manufacturing cost can be reduced accordingly.

Each first notch 53g cuts out the first restraining portion 53d in the radial direction of the first plate 53, and each second notch 54g cuts out the second restraining portion 54d in the radial direction of the second plate 54. notched in As a result, in this electric compressor, the restraining force, that is, the rigidity required to separate the magnetic steel plates 510 from each other by the first and second plates 53 and 54 and to prevent the magnet cores 52 from falling out of the receiving holes 51c is secured. However, by dividing the first and second restraining portions 53d and 54d into five, the rigidity of the first and second restraining portions 53d and 54d as a whole can be preferably reduced. In this respect as well, in this electric compressor, it is possible to suitably reduce the restriction in the direction of the drive axis O to the specific region 511 by the first and second restriction portions 53d and 54d.

Further, in this electric compressor, five through holes 51b are formed in the rotor body 51 around the outer periphery of the fixing hole 51a. In the first and second plates 53 and 54, five first and second communication holes 53b and 54b are formed corresponding to each through hole 51b. As a result, in this electric compressor, the refrigerant gas drawn into the motor chamber 111 can preferably flow through the through holes 51b and the first and second communication holes 53b and 54b. In this way, in this electric compressor, the flow rate of the refrigerant gas flowing inside the rotor 5b can be suitably increased, and the refrigerant gas can be suitably introduced into the compression mechanism 7. As shown in FIG. Further, in this electric compressor, the flow rate of the refrigerant gas flowing through the inside of the rotor 5b is increased, so that the rotor 5b can be sufficiently cooled by the refrigerant gas.

Although the present invention has been described above with reference to the embodiments, it is needless to say that the present invention is not limited to the above embodiments, and can be appropriately modified and applied without departing from the scope of the invention.

For example, in the electric compressor of the embodiment, the first and second notches 53g and 54g penetrate the first and second plates 53 and 54 in the drive axis O direction. However, the first and second cutouts 53g and 54g may be formed without penetrating the first and second plates 53 and 54 in the direction of the drive axis O, like a concave groove.

In addition to the fixing hole 51a, the large-diameter portion 3b of the drive shaft 3 may also be fixed to the first insertion hole 53a and the second insertion hole 54a.

Furthermore, in shrink-fitting the large-diameter portion 3b of the drive shaft 3 into the fixing hole 51a, the rotor 5b may be heated using a heating furnace or the like instead of induction heating.

Further, instead of shrink fitting, the large diameter portion 3b of the drive shaft 3 may be fitted into the fixing hole 51a by press fitting or the like.

Furthermore, as the compression mechanism 7, a vane compression mechanism, a swash plate compression mechanism, or the like may be employed.

Also, the compression mechanism 7 may compress a fluid other than the refrigerant gas.

Furthermore, in the electric compressor of the embodiment, the through holes 51b and the first and second communication holes 53b and 54b are made to function as introduction passages for the refrigerant gas, so that the refrigerant gas sucked into the motor chamber 111 can pass through the respective passages. This refrigerant gas cools the rotor 5b while flowing through the hole 51b and the first and second communication holes 53b and 54b. However, the present invention is not limited to this, and the rotor 5b can be made lighter by drawing the refrigerant gas into a place other than the motor chamber 111 in the housing 1 for each through hole 51b and each of the first and second communication holes 53b and 54b. It may be made to function as a lightening portion for softening.

INDUSTRIAL APPLICABILITY The present invention can be used for air conditioners such as vehicles.

DESCRIPTION OF SYMBOLS 1... Housing 3... Drive shaft 5... Motor mechanism 5a... Stator 5b... Rotor 7... Compression mechanism 51... Rotor main body 51a... Fixing hole (insertion hole)
51b... Through hole (communication hole)
52... Magnet core (permanent magnet)
53... First plate (plate)
53a... First insertion hole (insertion hole)
53b... First communicating hole (communicating hole)
53g... First notch (notch)
54 ... second plate (plate)
54a... Second insertion hole (insertion hole)
54b...Second communication hole (communication hole)
54g...Second notch (notch)
56 ... fastening pin (fastener)
510... Electromagnetic steel sheet (steel sheet)
535, 536... Second pin holes (fastening holes)
545, 546... Third pin hole (fastening hole)
555, 556... First pin holes (fastening holes)
O... Drive shaft center

Claims (2)

a housing;
a drive shaft provided within the housing and rotatable about a drive axis;
a motor mechanism provided in the housing for rotating the drive shaft;
An electric compressor comprising a compression mechanism provided in the housing and driven by the drive shaft to compress a fluid,
The motor mechanism has an annular stator fixed within the housing and a rotor disposed within the stator,
The rotor includes a rotor body made of a plurality of steel plates laminated in the drive shaft center direction, a plurality of permanent magnets provided in the rotor body, and a wall thickness greater than that of each of the steel plates. a pair of plates sandwiched in the direction of the drive axis; and a plurality of fasteners for fastening the rotor body and the plates in the direction of the drive axis,
Each of the steel plates and each of the plates includes an insertion hole through which the drive shaft is inserted, a plurality of communication holes positioned on the outer peripheral side of the insertion hole and arranged in the circumferential direction of the insertion hole, and a circumference of the insertion hole. a fastening hole through which the fastener is inserted and positioned between the communicating holes adjacent in the direction, and a fastening hole not positioned between the communicating holes adjacent in the circumferential direction of the insertion hole and through which the fastener is inserted. A fastening hole through which the fastener other than the fastener inserted in the fastening hole positioned between the communicating holes adjacent in the circumferential direction of the hole is inserted is formed,
The drive shaft is fitted into the through hole formed in each steel plate,
An electric compressor according to claim 1, wherein each plate is formed with a notch that communicates with the through hole formed in each plate and the communication hole and faces the rotor main body. 2. The electric compressor according to claim 1, wherein said notch penetrates each of said plates in the direction of said drive shaft.

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