JP6525371B1 - Rotating electrical machine and elevator door apparatus using the same - Google Patents

Abstract

The rotary electric machine has a housing, a rotation shaft, a rotation angle detection device, an outer cover made of a magnetic body, and an inner cover made of a magnetic body. The rotation angle detection device has a magnetic generator provided at an end of the rotation shaft and a magnetic sensor facing the magnetic generator. The outer cover is attached to the housing on the side opposite to the rotation axis with respect to the magnetic sensor. The inner cover is disposed between the magnetic sensor and the outer cover. An air gap is provided between the portion of the inner cover facing the magnetic sensor and the outer cover.

Description

  The present invention relates to a rotating electrical machine having a rotation angle detection device, and an elevator door device using the same.

  In general, a magnetic sensor detects the rotation angle of a rotating body by a magnetic field from a magnetic generator provided on the rotating body. However, in the presence of an external magnetic field, the rotation angle may be erroneously detected due to the influence of the external magnetic field. Moreover, a magnetic sensor may lead to failure when it is exposed to a strong magnetic field such as a magnet for a long time.

  In a conventional electronic circuit device of an electric motor, a metal plate made of a material having a high permeability is disposed as a magnetic shield in the vicinity of the sensor in order to suppress the influence of the magnetic field caused by the current flowing through the power substrate to the magnetic sensor. (See, for example, Patent Document 1).

  In the conventional magnetic shield device, a box-like inner magnetic shield is provided inside the box-like outer magnetic shield. Further, a plurality of nonmagnetic spacers are interposed between the outer magnetic shield and the inner magnetic shield (see, for example, Patent Document 2).

Patent No. 6182486 gazette Japanese Patent Application Laid-Open No. 57-8000

  The elevator door motor is relatively easily accessible by the elevator user than other elevator equipment. For this reason, when applying a rotating electrical machine having a rotation angle detection device using a magnetic sensor to a door motor of an elevator, in order to reduce the failure rate of the magnetic sensor, the magnet is brought near to the magnetic sensor Measures are necessary.

  On the other hand, in the magnetic shield of Patent Document 1, in order to cope with a strong magnetic field such as a magnet, the thickness of the metal plate is increased. However, since the cover of the door motor is generally manufactured by drawing or bending, when the thickness of the metal plate is increased, the processability is reduced. In addition, the thickness of the entire cover after processing also increases, which hinders the miniaturization of the door motor.

  Further, the magnetic shield device of Patent Document 2 does not consider application to the rotation angle detection device provided at the shaft end of the rotating electrical machine, and has a structure surrounding the object, so the magnetic field from the magnetism generator is also It is cut off.

  The present invention has been made to solve the above-mentioned problems, and can effectively suppress the influence of an external magnetic field on a magnetic sensor provided at the end of the rotation shaft. An object of the present invention is to obtain a rotating electrical machine and an elevator door device using the same.

  The rotary electric machine according to the present invention has a housing having an opening, an axial end provided at the opening, and a rotary shaft rotatably supported by the housing, and a magnetic provided at the axial end. A rotation angle detection device that has a generator and a magnetic sensor facing the magnetic generator, and generates a signal according to the rotation angle of the rotation shaft, opposite to the rotation shaft with respect to the magnetic sensor A magnetic outer cover attached to the housing on the side, and a magnetic inner cover disposed between the magnetic sensor and the outer cover, and a portion of the inner cover facing the magnetic sensor An air gap is provided between the outer cover.

  In the rotating electrical machine of the present invention, the inner cover is disposed between the magnetic sensor and the outer cover. Also, an air gap is provided between the portion of the inner cover facing the magnetic sensor and the outer cover. Therefore, the influence of the external magnetic field on the magnetic sensor provided at the shaft end of the rotating shaft can be efficiently suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing of the rotary electric machine by Embodiment 1 of this invention. It is a front view which shows the magnetism generation unit of FIG. It is sectional drawing in alignment with the III-III line of FIG. It is sectional drawing of the rotary electric machine by Embodiment 2 of this invention. It is the rear view which looked at the sensor substrate of FIG. 4 from the opposite side to the rotating shaft. It is sectional drawing which follows the VI-VI line of FIG. It is a front view which shows a part of elevator car which is an application example of the rotary electric machine of this invention. FIG. 8 is a side view of a portion of the car of FIG. 7;

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1
FIG. 1 is a cross-sectional view of a rotary electric machine according to Embodiment 1 of the present invention. In the figure, the housing 1 has a flat plate-like first shaft support part 1a and a flat plate-like second shaft support part 1b. The second shaft support portion 1b is opposed to the first shaft support portion 1a.

  A circular first opening 1c is provided at the center of the first shaft support 1a. A circular second opening 1 d is provided at the center of the second shaft support 1 b.

  A first bearing 2 is attached to the first opening 1c. The second bearing 3 is attached to the second opening 1d. The rotating shaft 4 is rotatably supported by the housing 1 via first and second bearings 2 and 3.

  A rotor 5 is provided on the rotating shaft 4. The rotor 5 has a rotor core 6 and a plurality of rotor magnets 7. The rotor core 6 is fixed to the rotating shaft 4. The rotor magnet 7 is fixed to the outer peripheral portion of the rotor core 6. The rotor 5 rotates integrally with the rotating shaft 4.

  A stator 8 is fixed to the housing 1. The stator 8 has a stator core 9 and a plurality of stator coils 10. The stator core 9 is fixed to the housing 1. The stator coil 10 is provided on a stator core 9. The stator 8 faces the rotor 5 via a gap.

  The rotation shaft 4 has a first shaft end 4a and a second shaft end 4b. The first shaft end 4 a is an end on the first shaft support 1 a side in the axial direction of the rotation shaft 4. The second shaft end 4 b is an end on the second shaft support 1 b side in the axial direction of the rotation shaft 4.

  The first shaft end 4a is provided in the first opening 1c. Further, the first shaft end 4a is held by the first bearing 2 in the first opening 1c. The second shaft end 4 b protrudes through the second bearing 3 and out of the housing 1.

  A shaft end recess 4 d is provided on the end face 4 c of the first shaft end 4 a. The shaft end recess 4 d is provided at the center of the end surface 4 c. The front shape of the shaft end recess 4d is circular.

  A disk-shaped magnetism generation unit 11 is provided in the shaft end recess 4d. The magnetism generation unit 11 rotates integrally with the rotation shaft 4. In this example, the entire magnetism generation unit 11 is accommodated in the shaft end recess 4d so that the magnetism generation unit 11 does not protrude from the end face 4c.

  Further, the shaft end recess 4 d and the magnetism generation unit 11 are disposed inside the first bearing 2. That is, the shaft end recess 4 d and the magnetism generation unit 11 are arranged at the same position as the first bearing 2 in the axial direction of the rotation shaft 4. Further, the end face 4 c is flush with the end face of the first bearing 2 opposite to the rotor 5.

  A substrate mounting recess 1e is formed on the surface of the first shaft support 1a opposite to the second shaft support 1b. The first opening 1c is provided at the center of the bottom surface of the substrate mounting recess 1e.

  The sensor substrate 12 is fixed in the substrate mounting recess 1e. The sensor substrate 12 is a printed circuit board. The sensor substrate 12 is fixed to the first shaft support 1 a by a plurality of substrate fasteners 13. For example, a bolt is used as each substrate fastener 13. In addition, the sensor substrate 12 closes the first opening 1 c.

  The sensor substrate 12 also has an inner surface 12a and an outer surface 12b. The inner surface 12 a faces the magnetism generation unit 11. The outer surface 12b is located opposite to the inner surface 12a.

  A magnetic sensor 14 is provided on the inner surface 12a. The magnetic sensor 14 is opposed to the magnetism generation unit 11 via a gap. Further, the magnetic sensor 14 detects the phase around the axis of the rotation shaft 4 from the magnetic state generated by the magnetic generation unit 11. For example, a magnetoresistive element is used as the magnetic sensor 14.

  The rotation angle detection device 15 has a magnetism generation unit 11, a sensor substrate 12, and a magnetic sensor 14. Further, the rotation angle detection device 15 generates a signal according to the rotation angle of the rotation shaft 4. When the rotating electrical machine is a motor, a signal generated by the rotation angle detection device 15 is sent to a control unit (not shown) that controls the rotation of the motor.

  An outer cover 16 made of a magnetic material is attached to the surface of the first shaft support 1a opposite to the second shaft end 4b. The outer cover 16 is attached to the housing 1 on the side opposite to the rotation shaft 4 with respect to the magnetic sensor 14.

  Further, the outer cover 16 is fixed to the first shaft support 1 a by a plurality of outer cover fasteners 17. As each outer cover fastener 17, for example, a bolt is used. The outer shape of the outer cover 16 is circular.

  The outer cover 16 has a peripheral edge portion 16a and a cover recess 16b which is an inner portion of the peripheral edge portion 16a. The outer cover fastener 17 is disposed at the peripheral portion 16a. The cover recess 16 b is formed by pushing the portion of the outer cover 16 excluding the peripheral edge portion 16 a to the side opposite to the rotation shaft 4.

  An inner cover 18 which is a flat plate made of a magnetic material is disposed between the magnetic sensor 14 and the outer cover 16. The inner cover 18 is disposed between the sensor substrate 12 and the outer cover 16. Further, the inner cover 18 covers the sensor substrate 12. Further, the inner cover 18 faces the outer surface 12 b with a gap.

  The outer shape of the inner cover 18 is circular. The peripheral portion of the inner cover 18 is sandwiched between the outer cover 16 and the first shaft support portion 1a. Thus, the inner cover 18 is fixed to the first shaft support 1 a. The outer cover 16 also covers the inner cover 18.

  An air gap 19 is provided between the inner cover 18 and the outer cover 16. The air gap 19 is provided between the bottom surface of the cover recess 16 b and the inner cover 18. Further, the air gap 19 is disposed between the outer cover 16 and at least a portion of the inner cover 18 facing the magnetic sensor 14.

  An annular packing 20 is sandwiched between the outer peripheral portion of the outer cover 16 and the first shaft support portion 1 a. Thereby, the packing 20 is fixed to the first shaft support portion 1a.

  FIG. 2 is a front view showing the magnetism generation unit 11 of FIG. 3 is a cross-sectional view taken along the line III-III in FIG. The magnetism generating unit 11 has a case 41 and a disc-shaped magnetism generating body 42. The magnetism generator 42 is accommodated in the case 41.

  The case 41 has a cylindrical portion 41a and a disc-like bottom portion 41b. The bottom 41 b closes one end of the cylindrical portion 41 a in the axial direction. The cylindrical portion 41 a protrudes to the magnetic sensor 14 side more than the surface of the magnetic generator 42 facing the magnetic sensor 14.

  Notches 41 c are provided at a plurality of locations in the circumferential direction of the cylindrical portion 41 a. The notch 41 c is used at the time of positioning of the magnetism generation body 42 in the circumferential direction. In this example, two notches 41c are provided in the cylindrical portion 41a.

  The case 41 is made of a nonmagnetic material. As a material of the case 41, for example, resin, aluminum or brass is used.

  The magnetism generation body 42 integrates two semicircular permanent magnets. The two permanent magnets are oppositely magnetized in the axial direction of the rotation axis 4. That is, the N pole of one permanent magnet and the S pole of the other permanent magnet face the magnetic sensor 14. The center of the magnetism generator 42 is located on the axis of the rotating shaft 4.

  The magnetism generation body 42 can be formed, for example, by magnetizing the material of the bond magnet after injecting it into the case 41. Alternatively, the magnetized disk-like magnetism generating body 42 may be fitted into the case 41.

  In order to detect the relative angle between the rotor magnet 7 and the stator coil 10, the magnetism generating body 42 needs to be adjusted to an angle with respect to the rotor magnet 7. That is, the magnetism generating body 42 needs to be positioned in the circumferential direction of the rotating shaft 4. The notch 41 c is used for circumferential positioning of the magnetism generator 42.

  The case 41 is fixed in the shaft end recess 4d by an adhesive. After the case 41 is inserted into the shaft end recess 4d, before the adhesive cures, the jig or the finger of the worker is hooked on the notch 41c and the case 41 is rotated to position the magnetism generating member 42 in the circumferential direction To be done. After this, the adhesive is cured.

  The end face 4c of the rotating shaft 4 is provided with a mark when positioning the magnetism generating body 42. In this example, the notch 41c is disposed on the extension of the boundary of the two permanent magnets, and the notch 41c itself serves as a mark for positioning on the magnetic generator 42 side.

  In such a rotating electrical machine, an inner cover 18 is disposed between the magnetic sensor 14 and the outer cover 16. Further, an air gap 19 is provided between the portion of the inner cover 18 facing the magnetic sensor 14 and the outer cover 16. Therefore, the influence of the external magnetic field on the magnetic sensor 14 can be suppressed while suppressing the increase in the plate thickness of the outer cover 16 and the inner cover 18. Thereby, the deterioration of the processability of the outer cover 16 and the inner cover 18 is suppressed, and the influence of the external magnetic field on the magnetic sensor 14 provided at the first shaft end 4 a is efficiently suppressed. it can.

  Therefore, even when a strong magnetic field such as a magnet is approached from the outside, the influence of the strong magnetic field on the magnetic sensor 14 can be effectively suppressed.

  Further, the packing 20 is sandwiched between the outer cover 16-and the first shaft support portion 1 a. For this reason, the waterproof property with respect to the sensor substrate 12 can be ensured by simple structure.

  The outer cover 16 is attached to the first shaft support 1 a by an outer cover fastener 17. The edge of the inner cover 18 is sandwiched between the outer cover 16 and the first shaft support 1 a. For this reason, the inner cover 18 can be attached to the first shaft support portion 1a by a simple configuration.

  Further, since both the inner cover 18 and the packing 20 are sandwiched between the outer cover 16 and the first shaft support portion 1a, it is possible to suppress an increase in the axial dimension of the rotary electric machine.

  In addition, the influence of the external magnetic field can be suppressed while securing waterproofness, and the failure rate of the rotation angle detection device 15 can be reduced.

  The magnetism generation unit 11 is provided in the shaft end recess 4 d, and the shaft end recess 4 d and the magnetism generation unit 11 are disposed inside the first bearing 2. Therefore, the magnetic sensor 14 can be disposed close to the end face 4c, and the overall axial dimension can be reduced.

  Further, since the magnetism generating body 42 is accommodated in the case 41, the magnetism generating body 42 can be disposed at a more accurate position in the shaft end concave portion 4d while protecting the magnetism generating body 42.

  Further, since the case 41 made of nonmagnetic material is used, the magnetism generating body 42 can be easily formed in the case 41.

  Moreover, since the notch 41c is provided in the cylindrical part 41a, positioning of the circumferential direction of the magnetic generation body 42 can be performed easily and more correctly.

Second Embodiment
Next, FIG. 4 is a cross-sectional view of a rotating electrical machine according to a second embodiment of the present invention. In the second embodiment, a magnetic inner cover 43 is attached to the sensor substrate 12 instead of the inner cover 18 of the first embodiment. The cross-sectional shape of the inner cover 43 is U-shaped. An air gap 19 is provided between the inner cover 43 and the outer cover 16. The other configuration is the same as that of the first embodiment.

  FIG. 5 is a rear view of the sensor substrate 12 of FIG. 4 as viewed from the side opposite to the rotation axis 4. 6 is a cross-sectional view taken along the line VI-VI of FIG. The inner cover 43 has a rectangular flat cover body 43a and a pair of cover connecting portions 43b.

  The cover body 43 a is disposed between the outer surface 12 b and the outer cover 16. Moreover, the cover main body 43a is facing the outer surface 12b via the clearance gap. Further, the cover main body 43 a covers the magnetic sensor 14 when the sensor substrate 12 is viewed from the outer cover 16 side.

  The cover connection portion 43 b protrudes from the mutually opposing edge portions of the cover main body 43 a toward the sensor substrate 12 and is connected to the sensor substrate 12. Further, each cover connection portion 43 b is soldered to the sensor substrate 12.

  Also with such a configuration, the same effect as that of the first embodiment can be obtained.

  Further, since the inner cover 43 is attached to the sensor substrate 12, the inner cover 43 can be reduced in size and weight.

  Further, since the cover main body 43a is opposed to the outer surface 12b through the gap, the influence of the external magnetic field on the magnetic sensor 14 can be suppressed more efficiently.

  In addition, since the inner cover 43 is soldered to the sensor substrate 12, the inner cover 43 can be easily attached to the sensor substrate 12.

  In the second embodiment, the outer shape of the cover main body 43a is rectangular, but may be, for example, circular.

  Further, the number of cover connection portions 43 b is not particularly limited. Further, the cover connection portion 43b may be provided continuously over the entire circumference of the cover main body 43a. For example, the cover main body 43a may be formed in a disk shape, and the cover connection portion 43b may be formed in a cylindrical shape.

  Moreover, in Embodiment 1, 2, the external shape of the outer cover 16 was made circular, and the annular packing 20 was used. However, the outer shape of the outer cover 16 and the shape of the packing are not particularly limited. For example, the outer shape of the outer cover 16 may be rectangular, and a rectangular packing 20 may be used.

  Further, in the first and second embodiments, the packing 20 is sandwiched between the outer cover 16 and the first shaft support portion 1a. However, the packing 20 may be integrated with the outer cover 16 in advance. Also, the packing 20 may be omitted.

  The magnetic sensor 14 is not limited to the magnetoresistive element, and may be, for example, a Hall element, a Hall IC, or a magnetic encoder.

  Here, FIG. 7 is a front view showing a part of an elevator car that is an application example of the rotating electrical machine of the present invention. FIG. 8 is a side view of a portion of the car of FIG. 7; A car entrance 21 a is provided on the front side which is a surface on the landing side of the car 21. The car entrance 21a is opened and closed by the first and second car doors 22a and 22b.

  The first and second car doors 22a and 22b each include a door panel 23 and a door hanger 24. Each door hanger 24 is fixed to the top of the corresponding door panel 23. Each door hanger 24 is provided with a plurality of hanger rollers 25.

  At the top of the front of the car 21, a girder 27 is fixed. The girder 27 is disposed above the car entrance 21a. A hanger rail 28 is provided at the girder 27. The first and second car doors 22a and 22b are suspended from the hanger rail 28 and move along the hanger rail 28 when the car entrance 21a is opened and closed. In addition, the hanger roller 25 rolls on the hanger rail 28 and moves while opening and closing the first and second car doors 22a and 22b.

  A door motor 29, which is a rotating electric machine, is fixed to one end of the crossbar 27 of the car entrance 21a in the width direction. As the door motor 29, the rotary electric machine of the first or second embodiment can be used. The door motor 29 is disposed such that the rotation axis 4 is horizontal and parallel to the depth direction of the car 21. A first pulley 30 is fixed to the second shaft end 4 b of the rotation shaft 4 of the door motor 29.

  A second pulley 31 is rotatably provided at the other end of the girder 27 in the width direction of the car entrance 21 a. An endless belt 32 is wound around the first pulley 30 and the second pulley 31.

  The first car door 22a is connected to the upper portion of the belt 32 via the first connection member 33a. The second car door 22b is connected to the lower portion of the belt 32 via the second connection member 33b. By rotating the first pulley 30 by the door motor 29, the first and second car doors 22 a and 22 b open and close along the hanger rails 28.

  The door motor 29 is disposed in front of the front of the car 21. The ceiling 21 b of the car 21 is located above the door motor 29. In other words, the door motor 29 is disposed at a lower position than the ceiling 21 b.

  The door device includes the first and second car doors 22a and 22b, the girder 27, the door motor 29, the first pulley 30, the second pulley 31, the belt 32, the first connection member 33a, and the second connection member. It has 33b.

  In such an elevator car 21, since the thin rotary electric machine as shown in the above embodiment is used as the door motor 29, the ceiling 21 b is increased without changing the size of the door device, The design of the car 21 can be improved.

  If the axial dimension of the door motor 29 is large, the door motor 29 can not be disposed in front of the car 21 and needs to be disposed on the ceiling 21 b. In this case, a mechanism for transmitting the output of the door motor 29 from the ceiling 21b to the first pulley 30 is required, and the door apparatus becomes large.

  Moreover, the failure rate of the rotation angle detection apparatus 15 can be reduced with respect to the mischief by the elevator user.

  In addition, the rotary electric machine of this invention is applicable also to electric motors other than the door motor 29 of an elevator, a generator, and a generator motor.

  Reference Signs List 1 housing, 1c first opening, 4 rotation shaft, 4a first shaft end, 12 sensor substrate, 12a inner surface, 12b outer surface, 14 magnetic sensor, 15 rotation angle detection device, 16 outer cover, 16b cover recess, Reference Signs List 17 outer cover fastener, 18, 43 inner cover, 19 air gap, 20 packing, 21a car door, 22a first car door, 22b second car door, 27 girder, 29 door motor (rotary electric machine), 42 magnetism generator , 43a cover body, 43b cover connection part.

Claims (7)

A housing with an opening,
A rotary shaft having an axial end provided in the opening and rotatably supported by the housing;
A rotation angle detection device having a magnetism generator provided at the shaft end and a magnetic type sensor facing the magnetism generator, which generates a signal according to the rotation angle of the rotation shaft ,
An outer cover made of a magnetic material attached to the housing on the side opposite to the rotation shaft with respect to the magnetic sensor, and a magnetic material disposed between the magnetic sensor and the outer cover Equipped with an inner cover
An air gap is provided between the portion of the inner cover facing the magnetic sensor and the outer cover ,
A packing is sandwiched between the outer cover and the housing,
The rotary electric machine wherein the inner cover is flush with the packing . The outer cover is attached to the housing by a plurality of outer cover fasteners,
It said edge portion of the inner cover, the rotary electric machine according to claim 1 Symbol placement is sandwiched between the outer cover and the housing. It further comprises a sensor substrate having an inner surface facing the magnetism generator and an outer surface opposite to the inner surface, the sensor substrate being attached to the housing,
The magnetic sensor is attached to the inner surface,
The inner cover is disposed and the cover body is, the rotary electric machine according to claim 1 Symbol placement and a cover connecting portion connected to the sensor substrate between said outer cover and said outer surface. The rotary electric machine according to claim 3 , wherein the cover body faces the outer surface with a gap. The cover connecting portion, the rotary electric machine according to claim 3 or claim 4 are soldered to the sensor board. The outer cover has a cover recess,
The rotary electric machine according to any one of claims 1 to 5 , wherein the air gap is provided between a bottom surface of the cover recess and the inner cover. The car door, which opens and closes the car entrance,
The rotary electric machine according to any one of claims 1 to 6 , further comprising: a girder disposed above the car doorway, and a door motor provided on the girder for moving the door panel. Elevator door equipment.

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