JP2011144758A - Sealed type motor-driven compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed type motor-driven compressor with excellent operating performance by preventing magnetic flux from leaking off a rotary shaft, as improvement of a conventional sealed compressor having an electric motor whose rotary shaft consists of a magnetic substance, involving such problems that a leakage of magnetic flux through the shaft is inevitable, the interlinkage magnetic flux with a stator decreases, and that the motor efficiency drops accordingly. <P>SOLUTION: A non-magnetic boss 16 is in advance fixed to the bore of a rotor 1, and leakage of the magnetic flux to the shaft is eliminated by fixing the boss to the rotary shaft 4, while a maximum space is secured between a core and the boss, and thereby leakage of the magnetic flux is lessened furthermore. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hermetic electric compressor used for an air conditioner / cooler.

  In general, the rotor and the rotating shaft of a brushless motor used in a conventional hermetic electric compressor are fixed by shrinkage fixing.

JP 2001-012374 A

  However, in the above conventional fixing method, since the rotating shaft is a magnetic body, it is inevitable that the magnetic flux leaks through the shaft, and the interlinkage magnetic flux with the stator is reduced, and the motor efficiency is reduced accordingly. Had.

  The present invention solves such a conventional problem, and an object of the present invention is to provide a sealed electric compressor having excellent performance by preventing leakage from a rotating shaft of magnetic flux.

  In order to solve the above-mentioned conventional problems, the rotor of the brushless motor used in the hermetic electric compressor of the present invention has a non-magnetic boss on the inner diameter and a stress strain between the rotor core and the rotor in advance. It is fixed in the axial direction so as not to occur, and can be held at a position where the influence of the distortion of the boss when the boss and the shaft are fixed is small.

  With the configuration of the rotor of the present invention, it is possible to obtain a hermetic electric compressor that is excellent in performance while suppressing a decrease in interlinkage magnetic flux.

Assembly sectional view of the rotor according to Embodiment 1 of the present invention The perspective view of the fixing boss | hub in Embodiment 1 of this invention Sectional drawing of the hermetic type electric compressor in Embodiment 1 of this invention

  1st invention is a rotor which comprises the brushless motor used for a hermetic type electric compressor, Comprising: A nonmagnetic boss is diameter-adjusted beforehand to the internal diameter of the said rotor which consists of the structure built in the iron plate which laminated | stacked the magnet. By fixing in the direction of the rotation axis so that no distortion occurs in the direction, and mechanically fixing to the rotation axis through the boss, loss due to magnetic flux leakage can be suppressed without causing loss due to core distortion. it can.

  In the second invention, a large space is provided in the boss portion between the boss and the rotor core of the first invention to form a refrigerant passage, and only in a portion that is not easily affected by distortion when the boss is fixed to the shaft. By making contact with the core, it is possible to prevent distortion when the rotating shaft and the boss are fixed from being transmitted to the core.

Embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is an assembled cross-sectional view of a rotor in a first embodiment of a brushless motor of the present invention. In the figure, non-magnetic fixing bosses 16 are fitted in the mounting holes 14 of the stator yoke 12 made of laminated iron plates in which a flat magnet 13 is housed in the direction of the rotation axis of the rotor yoke 12, and the caulking pins 15, 19. And are fixed together with the end plates 17a and 17b.

  FIG. 2 is a perspective view showing the shape of the fixing boss 16. In the figure, a mounting hole 22 of the rotating shaft 4, a pin hole 18 for fixing the yoke in the axial direction, a space 21 for refrigerant passage, and a fitting portion 20 that contacts the mounting hole 14 of the rotor yoke 12 are provided. . Here, the fitting part is an intermediate fit.

  FIG. 3 is a partial cross-sectional view of a hermetic electric compressor using the brushless motor rotor according to the first embodiment of the present invention.

  In the figure, reference numeral 1 denotes the stator, which is squeezed and fixed to the shell shell 6, and forms a motor with the rotor 2 fixed to the rotary shaft 4 of the mechanical part 3 of the compressor. The bearing 5 that supports the rotating shaft is formed integrally with the mechanical portion. The upper and lower shells 7 and 8 and the shell shell 6 form a pressure vessel. The pressure vessel is provided with an accumulator, discharge pipes 9 and 10 and a terminal 11 for supplying power to the motor, thereby forming a compressor. .

  The effects of the rotor configured as described above will be described below.

  First, the rotor yoke and the boss are fixed in the axial direction, and in the radial direction, there is no radial stress strain that works during shrinkage due to the engagement of the intermediate flange.

  In addition, by providing the contact surface between the rotor inner diameter and the boss at a portion where the core distortion is unlikely to occur (in this embodiment, the position of the core caulking pin), the distortion at the time of the boss shrinkage is hardly transmitted to the core. Stress strain can be minimized.

  Furthermore, since the space provided in the boss can have sufficient thickness strength, it can be made larger than the space provided in the laminated core.

  As described above, in this embodiment, it is possible to realize a rotor in which a non-magnetic boss is fixed in advance in the direction of the rotation axis so that no distortion occurs in the radial direction of the core, and the distortion when fixing to the rotation axis is small Therefore, the effect of reducing magnetic flux leakage can be obtained without increasing loss due to core distortion.

  In addition, since the space for the refrigerant passage can be made large, the leakage of magnetic flux to the shaft is further eliminated, and furthermore, the temperature rise is suppressed by the refrigerant flowing closer to the built-in magnet, and loss due to thermal demagnetization also occurs. There is also an effect that it is reduced.

  As described above, the rotor of the present invention can be applied to all hermetic electric compressors using a brushless motor.

1 Rotor
2 Stator 3 Mechanical part 4 Rotating shaft 5 Bearing 6 Body shell 7 Upper shell 8 Lower shell 9 Accum 10 Discharge pipe 11 Power supply terminal 12 Rotor yoke 13 Magnet 14 Mounting hole 22 Mounting hole 15 Caulking pin 19 Caulking pin 16 Boss 17a End plate 17b End plate 18 Pin hole 20 Fitting part 21 Space

Claims (2)

A rotor constituting a brushless motor used in a hermetic type electric compressor, wherein a non-magnetic boss is preliminarily distorted in a radial direction on the inner diameter of the rotor having a structure in which magnets are laminated on an iron plate. A hermetic electric compressor fixed in the direction of the rotation axis so as not to be fixed and mechanically fixed to the rotation axis via the boss. 2. A space is provided on the boss side between the boss for fixing the rotor and the core to form a coolant passage, and the core is contacted only at a portion that is not easily affected by distortion when the boss is fixed to the shaft. Hermetic type electric compressor.