JP5037827B2 - Mounting structure of hall sensor in electric motor - Google Patents

Description

  The present invention relates to a mounting structure for a hall sensor in an electric motor.

  2. Description of the Related Art Conventionally, there is known an electric motor that detects a change in a magnetic pole of a rotor by a Hall sensor, applies a voltage to an exciting coil in response to the change in the magnetic pole, and controls the rotation of a rotor and a rotating shaft connected to the rotor. . At this time, the Hall sensor is disposed in the axial direction of the rotating shaft so as to face the magnetic pole portion of the rotor, and is disposed via a gap so as to maintain insulation with respect to the exciting coil (for example, Patent Documents 1 and 2).

In addition, the electric motor and the speed reducer are integrally joined, and a sealing member is provided at the joint so that the lubricant that lubricates the gear mechanism in the speed reducer does not flow into the case of the electric motor. There are some (see, for example, Patent Document 3).
JP 2005-160296 A JP 2006-25586 A JP 2004-108521 A

  According to the conventional Hall sensor mounting structure of an electric motor, the size in the axial direction is limited by the insulation distance (gap) between the exciting coil and the Hall sensor, and it is difficult to reduce the size. In addition, when the electric motor is joined to the speed reducer and the sealing at the joint between the electric motor and the speed reducer is broken, the lubricant flows into the case of the electric motor and the hall sensor and the hall sensor. There is a risk that they will adhere to the circuit parts and damage them. That is, since metal powder such as wear powder is mixed in the lubricant that lubricates the gear mechanism, there is a possibility that an electrical short circuit will occur if it adheres to the Hall sensor or its circuit part.

  Therefore, the present invention can reduce the size in the axial direction, improve the insulation between the Hall sensor and the exciting coil, and further, when a lubricant that lubricates the gear mechanism flows into the electric motor, It is an object of the present invention to provide a hall sensor mounting structure in an electric motor that can prevent the lubricant from adhering to the hall sensor and the circuit portion of the hall sensor.

The present invention, which has been made to achieve the above object, is a mounting structure for a hall sensor in an electric motor, wherein a rotating shaft and a plurality of magnetic poles are coaxially connected to the rotating shaft in the case and along the circumferential surface thereof. And a plurality of rotors arranged coaxially with the rotor and covering the outer periphery of the rotor via a gap, and projecting radially from the inner periphery of the stator toward the outer periphery of the rotor of the armature core, an excitation coil is concentratedly wound on the armature core are disposed so as to face the magnetic pole in the axial direction of the rotor, the change in the magnetic field of the rotor with the rotation operation of the rotor a Hall sensor detecting detects the amount of rotation of the rotor relative to the scan Te chromatography data, and an insulating material having oil resistance, the insulating material is formed in a ring shape having a shaped cross section of substantially C Along the axial direction The first and second side portions opposed to each other, a third side portion connecting both side portions, and the hole located between the first and second side portions in the radial direction Each of the first and second side portions is connected to the case, and a space in which the Hall sensor is disposed is disposed in the rotor and the stator. The space is defined and sealed via the insulating material .

According to this , since the insulating material is interposed between the excitation coil and the magnetic pole portion of the rotor and the Hall sensor, the insulation between the excitation coil and the Hall sensor can be improved compared with the case where no insulating material is interposed, and Therefore, the size of the electric motor in the axial direction can be reduced. In other words, it is possible to improve the insulation by arranging the exciting coil and the hall sensor through the insulating material rather than arranging them through the gap, so that the gap between the exciting coil and the hall sensor can be reduced and the size in the axial direction can be reduced. Can be downsized.

In addition, the insulating material has oil resistance, the insulating material is formed in an annular shape having a substantially U-shaped cross section, and the first and second side portions opposed to each other disposed along the axial direction, both sides A first side and a second side having a third side part connecting the parts and an annular part located between the first and second side parts in the radial direction and housing the Hall sensor Each of the parts is connected to the case, and a space in which the Hall sensor is arranged is defined and sealed via the insulating material with respect to a space in which the rotor and the stator are arranged . When the electric motor is used by being connected to a gear mechanism such as a speed reducer via a rotating shaft, even if the lubricant that lubricates the gear mechanism flows into the case of the electric motor, the lubricant remains in the Hall sensor and the circuit board. It can prevent so that it may not adhere to.

When the hall sensor is connected to a circuit board, and the hall sensor and the circuit board are provided on the opposite side of the output side of the rotary shaft via the rotor and the stator in the axial direction, an excitation coil and a hall sensor Can be maintained, and even if the lubricant flows into the case of the electric motor from the output side of the rotating shaft, the lubricant can be prevented from adhering to the Hall sensor and the circuit board.

Before SL case, the first case for housing the rotor and the stator is constituted by a second case connected to one axial end of the first case, the inner diameter of the annular portion of the insulating material The first side portion arranged on the side is connected to the second case, and the second side portion arranged on the outer diameter side is connected to the inner periphery of the first case. In this case, the space between the rotor, the stator and the output side of the rotating shaft and the space where the Hall sensor and the circuit board are stored can be sealed with an insulating material.

  The mounting structure of the hall sensor in the electric motor of the present invention has an insulating material interposed between the excitation coil and the magnetic pole part of the rotor and the hall sensor, so that the excitation coil and the hall sensor are compared with the case where no insulating material is interposed. Thus, the axial size of the electric motor can be reduced.

Further , when the electric motor is used by being connected to a gear mechanism such as a speed reducer via a rotating shaft, even if the lubricant that lubricates the gear mechanism flows into the case of the electric motor, the lubricant is It can be prevented from adhering to the circuit board.

Further , the insulation between the exciting coil and the hall sensor can be maintained , and the space between the output side of the rotor, the stator and the rotating shaft and the space where the hall sensor and the circuit board are housed can be sealed with an insulating material.

  Next, an embodiment of the electric ceramic kiln according to the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an electric motor to which a Hall sensor mounting structure in an electric motor according to an embodiment of the present invention is applied. FIG. 2 is a sectional view taken along line YY in FIG. It is SS sectional drawing in FIG.

  As shown in FIGS. 1 to 2, the electric motor 1 is a DC brushless type that includes a stator 2 and a rotor 3 that is coaxial with the stator 2 and disposed inside the stator 2. 4b and the rotating shafts 4a and 4b that are coaxially connected to each other, and a rotor 3 in which a plurality of permanent magnets 15 are arranged in parallel along the peripheral surface thereof, and the rotor 3 that is coaxially disposed with a gap interposed therebetween. 3, a stator 2 that covers the outer periphery of 3, a first case 10, a second case 11, and a third case 12.

  The first case 10, the second case 11, and the third case 12 are integrally fixed via bolts 13. The third case 12 is provided with a mounting hole 12a and a fitting hole 12b for connection with a speed reducer that transmits the driving force of the electric motor 1.

  The rotor 3 is configured integrally with the rotation shafts 4a and 4b so as to protrude on both sides in the axial direction, and the rotation shafts 4a and 4b rotate around the third case 12 and the second case 11 via bearings 14 and 16, respectively. It is supported freely. The rotation shaft 4a located on the third case 12 side is for transmitting a rotational driving force to a gear mechanism such as a speed reducer, and is provided so as to protrude outward from the third case 12. It has been.

  The rotor 3 includes a permanent magnet (so-called magnetic pole in the present invention) 15 along the circumferential direction. The permanent magnet 15 is made of a ferrite-based anisotropic rare earth magnet and has an S pole and an N pole in the radial direction (that is, on the outer peripheral surface side and the inner peripheral surface side). The plurality of permanent magnets 15 are arranged such that the respective S poles and N poles appear alternately on the outer peripheral surface side of the rotor 3.

  The permanent magnet 15 has S poles and N poles alternately arranged so as to face the exciting coil 9. In this embodiment, the permanent magnet 15 is composed of 10 poles, and the exciting coil 9 is composed of 12 U, V, and W three-phase elements alternately.

  The stator 2 includes a plurality of armature cores 2a that are press-fitted and supported in the first case 10 and project radially from the inner peripheral surface thereof toward the outer peripheral surface of the rotor 3, and each armature core 2a is excited. The coil 9 is concentratedly wound.

  The electric motor 1 detects a change in the magnetic field of the rotor 3 as the rotor 3 rotates, and detects a relative amount of rotation of the rotor 3 with respect to the stator 2 and a plurality of hall sensors 20a, 20b, 20c and a hall sensor 20a. , 20b, 20c are provided with a circuit board 21 mounted thereon. The hall sensors 20a, 20b, 20c and the circuit board 21 are provided on the opposite side of the output side rotating shaft 4a via the rotor 3 and the stator 2 in the axial direction.

  And the electric motor 1 rotates the rotor 3 and the rotating shafts 4a and 4b by energizing the exciting coil 9 through the cable, and changes the magnetic poles of the permanent magnet 15 to the Hall sensors 20a, 20b and 20c and the circuit board. The rotation speed and positioning are controlled by a controller (not shown).

  Next, the hall sensors 20a, 20b, 20c and the circuit board 21 are covered with an insulating material 22. Further, the circuit board 21 is fixed to the second case 11 via a metal fitting not shown, and the hall sensors 20a, 20b, and 20c are fixed to the circuit board 21.

  The insulating material 22 is formed in an annular shape having a substantially U-shaped cross section, and the first side portion 22 a and the second side portion 22 b facing each other in the U shape are arranged along the axial direction of the rotor 3. The third side portion 22c connecting the side portions 22a and 22b is disposed between the exciting coil 9 and the permanent magnet 15 of the rotor 3 and the plurality of hall sensors 20a, 20b, and 20c, and the hall sensors 20a, 20b, A plurality of 20c are accommodated along the annular portion 22d via the circuit board 21.

  The insulating material 22 is formed using a resin having electrical insulation properties, and the thickness of the third side portion 22c is set so as to satisfy desired insulating properties. Furthermore, the insulating material 22 is formed using a resin having oil resistance so that the lubricant that lubricates the gear mechanism is not eroded by the lubricant.

  In addition, the insulating material 22 has a first side portion 22a disposed on the inner diameter side of the annular portion 22d connected to the second case 11, and a second side portion 22b disposed on the outer diameter side defined by the first side portion 22a. It is comprised so that it may connect with the inner periphery of case 10 of this. A space in which the hall sensors 20a, 20b, and 20c are arranged is defined via an insulating material 22 with respect to a space in which the rotor 3, the stator 2, and the rotation shafts 4a and 4b are arranged.

  Next, the operation and effect of the mounting structure of the hall sensors 20a, 20b, 20c in the electric motor 1 of the embodiment will be described.

  The mounting structure of the hall sensors 20a, 20b, 20c in the electric motor 1 of the present embodiment is because the insulating material 22 is disposed between the excitation coil 9 and the permanent magnet 15 of the rotor 3 and the hall sensors 20a, 20b, 20c. Compared with the case where the insulating material 22 is not provided, the insulation between the exciting coil 9 and the hall sensors 20a, 20b, 20c can be improved, and the size of the electric motor 1 in the axial direction can be reduced.

  In addition, the mounting structure of the hall sensors 20a, 20b, and 20c in the electric motor 1 of the present embodiment is such that the hall sensors 20a, 20b, and 20c are connected to the circuit board 21, and the hall sensors 20a, 20b, and 20c and the circuit board 21 are Since it is provided on the opposite side of the rotating shaft 4a on the output side via the rotor 3 and the stator 2 in the axial direction, and the insulating material 22 is provided so as to cover the Hall sensors 20a, 20b, 20c and the circuit board 21, When the motor 1 is used by being connected to a gear mechanism such as a speed reducer via the rotating shaft 4a, even if a lubricant that lubricates the gear mechanism flows into the electric motor 1, the lubricant remains in the hall sensors 20a, 20b, It can prevent so that it may not adhere to 20c and the circuit board 21. FIG.

  In addition, the mounting structure of the hall sensors 20a, 20b, 20c in the electric motor 1 of the present invention is such that the insulating material 21 is formed in an annular shape having a substantially U-shaped cross section, and opposite side portions 22a in the U-shape are opposed to each other. 22b is disposed along the axial direction of the rotor 3 and the stator 2, and a third side 22c that connects the side portions 22a and 22b is formed between the exciting coil 9 and the permanent magnet 15 of the rotor 3 and the hall sensors 22a and 22b. A space in which the hall sensors 20a, 20b, and 20c are accommodated along the annular portion 22d and the hall sensors 20a, 20b, and 20c are disposed is a space in which the rotor 3 and the stator 2 are disposed. On the other hand, since it is defined via the insulating material 22, the insulation between the exciting coil 9 and the Hall sensors 20a, 20b, 20c can be improved, and the lubricant can rotate on the output side. Also flows into the electric motor 1 from 4a side, the lubricant can be prevented so as not to adhere to the Hall sensor 22a, 22b and the circuit board 21.

  In addition, the mounting structure of the hall sensors 20a, 20b, and 20c in the electric motor 1 of the present invention includes a first case 10 in which the case of the electric motor 1 houses the rotor 3 and the stator 2, and a shaft of the first case 10. The first side portion 22a, which is configured by the second case 11 connected to one end in the direction and arranged on the inner diameter side of the annular portion 22d of the insulating material 22, is coupled to the second case 11 and has an outer diameter. Since the second side portion 22b arranged on the side is connected to the inner periphery of the first case 10, a space and a hole for housing the rotor 3, the stator 2, and the rotating shafts 4a, 4b, and 20c. The space between the sensors 20a, 20b, 20c and the circuit board 21 can be sealed with an insulating material 22.

  As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example, Various sun can be taken.

It is sectional drawing of the electric motor to which the attachment structure of the hall sensor in the electric motor of one Example of this invention was applied. (A) is YY sectional drawing in FIG. 1, (b) is SS sectional drawing in FIG.

  DESCRIPTION OF SYMBOLS 1 ... Electric motor, 2 ... Stator, 2a ... Armature core, 3 ... Rotor, 4a, 4b ... Rotating shaft, 9 ... Excitation coil, 10 ... First case, 11 ... Second case, 12 ... Third Case, 12a ... mounting hole, 12b ... fitting hole, 13 ... bolt, 14, 16 ... bearing, 15 ... permanent magnet, 20a, 20b, 20c ... Hall sensor, 21 ... circuit board, 22 ... insulating material, 22a ... first One side, 22b ... second side, 22c ... third side, 22d ... annular part.

Claims (4)

In the case,
A rotation axis;
A rotor connected coaxially to the rotating shaft and having a plurality of magnetic pole portions arranged in parallel along the circumferential surface thereof;
A stator disposed coaxially with the rotor and covering the outer periphery of the rotor via a gap ;
A plurality of armature cores projecting radially from the inner periphery of the stator toward the outer periphery of the rotor;
An exciting coil that is concentratedly wound on the armature core,
Is arranged to face the magnetic pole in the axial direction of the rotor, the Hall sensor in accordance with the rotation of the rotor by detecting a change in the magnetic field of the rotor, detecting the amount of rotation of the rotor relative to the scan tape over data When,
An insulating material with oil resistance;
With
The insulating material is formed in an annular shape having a substantially U-shaped cross section, and the first and second side portions opposed to each other disposed along the axial direction and the third side connecting the both side portions. And an annular portion that is located between the first and second side portions in the radial direction and houses the Hall sensor,
Each of the first and second sides is coupled to the case;
A hall sensor in an electric motor , wherein a space in which the hall sensor is disposed is defined and sealed with respect to a space in which the rotor and the stator are disposed through the insulating material . Mounting structure. Claims wherein the Hall sensor is connected to the circuit board, the Hall sensor and the circuit board in the axial direction through the rotor and the stator are provided on the opposite side of the output side of the rotary shaft, characterized in that Item 2. A mounting structure of a Hall sensor in the electric motor according to Item 1. The case has a first case that houses the rotor and the stator, and a second case connected to one end in the axial direction of the first case,
The first side portion disposed on the inner diameter side of the annular portion of the insulating material is connected to the second case, and the second side portion disposed on the outer diameter side is connected to the inner side of the first case. The mounting structure of the hall sensor in the electric motor according to claim 1, wherein the mounting structure is connected to a circumference . The mounting structure of the hall sensor in the electric motor according to claim 2, wherein a gear mechanism is connected to an output side of the rotating shaft .

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