JP4622363B2 - Mounting structure of rotation detector for electric motor - Google Patents

Description

  The present invention relates to a rotation detector mounting structure for mounting a rotation detector on an electric motor having a so-called coaxial motor structure. The present invention relates to a rotation detector deterioration prevention technique.

  For example, a rotation detector is attached to an electric motor (drive motor) that is a drive source of an electric vehicle in order to detect the rotation position of the rotor shaft (see, for example, Non-Patent Document 1).

The electric motor described in Non-Patent Document 1 is a so-called coaxial type in which an output shaft that transmits power output from an operating portion provided in a transaxle to a wheel is passed through the rotor shaft. This is an electric motor structure. Further, in the electric motor described in Non-Patent Document 1, by providing a rotation detector inside the bearing that supports the rotor shaft, the lubricating oil supplied to the bearing that supports the rotation of the output shaft is reduced. The rotation detector is isolated from the flowing lubricant supply chamber.
Masao Kinoshita and one other, “About the electric car“ RAV4EV ””, TOYOTA Technical Review, November 1997, Vol. 47, No. 2, p. 41

  However, in this structure, the electric zero position adjustment of the rotation detector is performed across the wall supporting the bearing (the stator of the rotation detector is rotated in the circumferential direction for the purpose of correcting the assembly error) It is necessary to carry out adjustment to adjust the electrical zero position of the rotation detector. In the electric zero position adjustment, in order to ensure the rigidity of the casing of the transaxle, a small peephole is formed in the casing and the position is adjusted by looking through the peephole.

  However, such an electrical zero position adjustment operation is forced to be a relatively inconvenient operation through the peephole, and the operation is troublesome. Further, in such a structure, since a rotation detector must be arranged near the magnet coil of the electric motor that generates electromagnetism, there is a concern about noise interference from the magnet coil to the rotation detector.

  Therefore, the present invention has been made to solve the above-described problem, and even if there is a lubricant supply chamber accompanying the lubricant supply to the bearing that supports the output shaft, which is the fate of the coaxial motor, The rotation detector can be attached to the end of the electric motor, the electric zero position can be adjusted easily, and there is no fear of deterioration of the rotation detector due to lubricating oil. An object of the present invention is to provide a mounting structure for a rotation detector for an electric motor that can reduce noise interference with the motor.

  The electric motor rotation detector mounting structure of the present invention has an electric motor and a reduction gear arranged in series on the same shaft, and the power output from the differential gear provided in the reduction gear is applied to the wheels. The output shaft to be transmitted has a structure in which a rotation detector that detects the rotational position of the rotor shaft is attached to a coaxial electric motor that passes through the rotor shaft of the electric motor. .

  In this electric motor rotation detector mounting structure, the rotation detector is a bearing that is on the shaft end side of the rotor shaft opposite to the speed reducer and supports the rotor shaft. And a seal member that seals lubricating oil that flows through a space formed between the outer periphery of the output shaft and the inner periphery of the rotor shaft, outside the bearing, the rotation detector It is set as the structure arrange | positioned further outside.

  According to the present invention, the rotation detector is attached to the end of the electric motor even when there is a lubricant supply chamber accompanying the supply of the lubricant to the bearing that supports the output shaft, which is the fate of the coaxial motor. Thus, the electric zero position adjustment operation is remarkably improved, and there is no fear of deterioration of the rotation detector due to the lubricating oil.

  Further, according to the present invention, since the rotation detector can be arranged at a position away from the magnet coil of the electric motor, the influence of the magnet coil on the rotation detector is reduced, and stable rotation detection is achieved. Can be obtained.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  1 is a cross-sectional view showing a power train portion of an electric vehicle, FIG. 2 is an enlarged cross-sectional view showing a main portion of FIG. 1, FIG. 3 is an enlarged cross-sectional view of a main portion of a portion to which a rotation detector is attached, FIG. ) Is a plan view of the rotation detector, and FIG. 4B is a sectional view of the rotation detector.

  The power train is mainly composed of an electric motor (drive motor) 1 and a transaxle 2 attached to a side surface of the electric motor 1.

  The electric motor 1 is, for example, a normal permanent magnet type synchronous motor, and includes a cylindrical stator 3, a rotor 4 that is rotatably disposed inside the stator 3, the stator 3, and the rotation. It comprises a case 5 that houses the child 4 therein.

  The stator 3 includes a coil 6 that generates a magnetic flux and a stator core 7 that holds the coil 6 and forms a magnetic path through which the magnetic flux passes. On the other hand, the rotor 4 includes a rotor core 8 that contains a magnet and forms a magnetic path, and a rotor shaft 9 that has the rotor core 8 fixed around the rotor core 8.

  The rotor shaft 9 is formed as a cylindrical rotating shaft, and is rotatably supported by supporting the vicinity of both ends in the longitudinal direction on the respective bearings 10 and 11. One bearing 10 is provided on one end side (transaxle 2 side) of the case 5, and the other bearing 11 is fixed to the other end of the case 5 (on the opposite side to the transaxle 2) with a bolt. The casing 12 is fixed.

  Further, at one end of the rotor shaft 9, a speed reducer 13 and a differential gear device 14 constituting the transaxle 2 are arranged in series on the same shaft. The speed reducer 13 is composed of a plurality of gears and decelerates the rotation of the electric motor 1. The differential gear device 14 distributes the driving force decelerated by the speed reducer 13 to the left and right wheels via the output shaft 15 (the left output shaft is not shown).

  The right output shaft 15 is inserted into the cylindrical rotor shaft 9 and is rotatably supported by a rotor shaft rotating bearing 16 fixed to the inner wall of the rotor shaft 9. Although not shown, the left output shaft is similarly inserted into the rotor shaft 9 and is rotatably supported by a rotor shaft rotating bearing fixed to the inner wall of the rotor shaft 9. Yes.

  The output shaft 15 is connected to a drive shaft 17 to which wheels are attached. The space 18 formed between the outer periphery of the output shaft 15 and the inner periphery of the rotor shaft 9 is supplied with lubricating oil that lubricates each part of the speed reducer 13 and supports the output shaft 15. After lubricating the rotor shaft rotation bearing 16, it is discharged into a lubricating oil supply oil chamber 19 provided at the rear end of the electric motor 1.

  The lubricating oil supply oil chamber 19 is provided between an end cover 20 attached to the rear end portion of the casing 12 and an oil seal 21 which is a seal member provided between the drive shaft 17 and between the end cover 12 and the rotor shaft 9. The oil seal 22 is partitioned. The lubricating oil supplied to the lubricating oil supply oil chamber 19 is sealed by these oil seals 21 and 22 so as not to leak to the outside.

  The electric motor 1 is provided with a rotation detector 23 for detecting the rotational position of the rotor shaft 9. The rotation detector 23 is arranged on the shaft end side of the rotor shaft 9 opposite to the transaxle 2 and outside the bearing 11 that supports the rotor shaft 9. Specifically, the rotation detector 23 is arranged between a bearing 11 that supports the rotor shaft 9 and an oil seal 22 provided between the casing 12 and the rotor shaft 9.

  As shown in FIGS. 3 and 4, the rotation detector 23 includes a rotor 24 attached to the rotor shaft 9, a stator 25 disposed on the outer periphery of the rotor 24, and the stator 25. And magnet coils 26 provided on both inner surfaces.

  The rotor 24 has a ring shape, is fixed to the outer periphery of the rotor shaft 9 and rotates together with the rotor shaft 9. The rotor 24 is provided between a bearing 11 that rotatably supports the rotor shaft 9 and an oil seal 22 provided between the end cover 20 and the rotor shaft 9. Therefore, the rotor 24 is protected by the oil seal 22 from the lubricating oil supplied to the lubricating oil supply oil chamber 19 in front of the rotor shaft tip. That is, the rotation detector 23 including the rotor 24 is not contaminated by the lubricating oil.

  The stator 25 has a larger ring shape than the rotor 24, and is fixed to the casing 12 by bolts 27 that are fastening means. A plurality of mounting holes 28 (five in this embodiment) are formed in the stator 25 in the circumferential direction through which the bolts 27 are inserted. These mounting holes 28 are used to adjust the zero position of the rotation detector 23 (adjustment work for aligning the electric zero positions of the electric motor 1 and the rotation detector 23 for the purpose of correcting assembly errors). It is a long hole so that the position can be adjusted by slightly rotating 25 in the circumferential direction.

  The magnet coil 26 is formed in a ring shape by winding a magnet wire, and is fixed to both inner surfaces of the stator 25 adjacent to the rotor 24. The magnet coil 26 is covered with a coil protection cover 29 to prevent dust and the like from entering the cover.

  In this rotation detector 23, a connector portion 30 for taking out the output obtained by the magnet coil 26 to the outside of the electric motor is attached to the stator 25. The connector portions 30 are provided at two opposing positions of the stator 25 and are attached only to one surface of the stator 25.

  The connector unit 30 includes a plurality of (six in this embodiment) connection pins 32 for connecting a magnet wire and an external lead wire 31 (not shown), and a terminal block on which the connection pins 32 are implanted. 33.

  Two of these connection pins 32 are arranged at a predetermined interval in the circumferential direction of the stator 25, and the arranged pin groups are arranged in three rows in the radial direction. The connection pin 32 has one end connected to a magnet wire and the other end connected to an external lead wire 31. The external lead wire 31 is pulled out from each connector portion 30 and routed along the magnet coil 26, and does not protrude from the stator 25. The external lead wires 31 drawn out from the connector portions 30 are finally gathered at one place.

  Further, the external lead wire 31 is covered with a protective cover 34 including the connector portion 30 so as not to contact the bolts 27 attached to the stator 25 and the like. The assembled external lead wires 31 are drawn out to the outside of the electric motor 1 through grommets 35 attached to the casing 12.

  In the electric motor rotation detector mounting structure of the present embodiment configured as described above, lubrication to the rotor shaft rotation bearing 16 that supports the output shaft 15 that is the fate of the coaxial motor. Even if there is a lubricating oil supply oil chamber 19 associated with oil supply, a rotation detector 23 is disposed outside the bearing 11 that supports the rotor shaft 9, and oil provided further outside the rotation detector 23. Since the rotation detector 23 is protected by the seal 22, the rotation detector 23 can be attached to the end of the electric motor. As a result, there is no fear of deterioration of the rotation detector 23 due to the lubricating oil.

  In the present embodiment, the zero position adjustment of the rotation detector 23 is performed by temporarily removing the end cover 20 from the casing 12 and rotating the stator 25 in the circumferential direction. Therefore, it is not necessary to form a viewing hole in the casing 12 as in the prior art, and to confirm the rotational position of the stator 25 by looking inside through the viewing hole, so that the electrical zero position adjustment operation can be greatly improved. it can.

  Further, in the present embodiment, the rotation detector 23 can be disposed at a position away from the electric motor 1, so that there is little influence from the magnet coil of the electric motor 1, and the rotation of the rotor shaft 9. The position can be detected accurately and stably.

  In the present embodiment, the rotation detector 23 can be reduced in size because the connector portion 30 is disposed outside the magnet coil 26 and at a position that does not protrude from the stator 25. Since the rotation detector 23 can be reduced in size, the opening of the casing 12 formed for attaching the rotation detector 23 can be reduced in diameter, and as a result, the rigidity of the casing 12 can be increased. .

  Further, in the present embodiment, the output from the magnet coil 26 can be easily taken out by providing the connector portions 30 at two locations of the stator 25, respectively.

  In the present embodiment, when the external lead wire 31 is routed along the magnet coil 26 and covered with the common protective cover 34, damage to the external lead wire 31 can be avoided.

  Although specific embodiments to which the present invention is applied have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.

  FIG. 5 shows another example, an enlarged cross-sectional view of the main part of the portion where the rotation detector is attached, FIG. 6 (A) is a plan view of the rotation detector of FIG. 5, and FIG. 6 (B) is the rotation of FIG. It is sectional drawing of a detector.

  In the embodiment shown in FIGS. 5 and 6, one connector portion 30 is provided, and the connector portion 30 is disposed between the two bolts 27 of the stator 25. The connector portion 30 includes connection pins 32 and a terminal block 33 as in the above-described embodiment, and the six connection pins 32 are arranged in a row in the circumferential direction of the stator 25 at a predetermined interval. , Which differs in that one end is passed through the stator 25. The magnet wire of the magnet coil 26 is connected to one end of the connection pin 32 that penetrates the surface opposite to the surface on which the terminal block 33 is provided.

  The external lead wires 31 are connected to the other ends of the connection pins 32 arranged in a row on the terminal block 33. These external lead wires 31 are gathered together and led out of the electric motor 1 through the grommet 35. The connector portion 30 is also covered with a protective cover 34 as in the above-described embodiment.

  In this embodiment configured as described above, one connector portion 30 is provided, and the connection pins 32 of the connector portion 30 are arranged in a line in the circumferential direction of the magnet coil 26. Further downsizing is possible.

It is a principal part expanded sectional view which shows the power train part of an electric vehicle. It is an expanded sectional view which shows the principal part of FIG. It is a principal part expanded sectional view of the part to which the rotation detector was attached. 4A is a plan view of the rotation detector, and FIG. 4B is a cross-sectional view of the rotation detector. It is a principal part expanded sectional view of the part to which the other example was shown and the rotation detector was attached. 6A is a plan view of the rotation detector of FIG. 5, and FIG. 6B is a cross-sectional view of the rotation detector of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electric motor 2 ... Transaxle 9 ... Rotor shaft 11 ... Bearing 12 ... Casing 13 ... Reduction gear 14 ... Differential gear apparatus 15 ... Output shaft 16 ... Bearing for rotor shaft rotation 18 ... Space part 19 ... Lubricating oil supply chamber 20 ... End cover 22 ... Oil seal 23 ... Rotation detector 24 ... Rotor 25 ... Stator 26 ... Magnet coil 29 ... Coil protection cover 30 ... Connector part 31 ... External lead wire 32 ... Connection pin 33 …Terminal block

Claims (6)

An electric motor and a speed reducer are arranged in series on the same shaft, and an output shaft that transmits power output from a differential device provided in the speed reducer to a wheel is provided in the rotor shaft of the electric motor. In the mounting structure of the rotation detector for the electric motor, in which the rotation detector for detecting the rotation position of the rotor shaft is attached to the coaxial electric motor passing through
The rotation detector is disposed on an end side of the rotor shaft opposite to the speed reducer and outside a bearing supporting the rotor shaft;
Further, a seal member that seals lubricating oil flowing in a space formed between the outer periphery of the output shaft and the inner periphery of the rotor shaft is provided outside the bearing and further outside the rotation detector. Mounting structure for a rotation detector for an electric motor, characterized in that An electric motor rotation detector mounting structure according to claim 1,
The rotation detector includes a magnet coil around which the magnet wire is wound, and includes a rotor attached to the rotor shaft and a disk-shaped stator disposed around the rotor,
A connector part formed by implanting a connection pin, one end of which is connected to the magnet wire and the other end of which is connected to an external lead wire, on the terminal block, is located outside the magnet coil and does not protrude from the stator. A structure for mounting a rotation detector for an electric motor, characterized by being provided in An electric motor rotation detector mounting structure according to claim 2,
An attachment structure for a rotation detector for an electric motor, wherein the connector portion is provided at each of two locations of the stator. An electric motor rotation detector mounting structure according to claim 2,
An attachment structure for a rotation detector for an electric motor, wherein the connector portion is provided at one location of the stator. A mounting structure for a rotation detector for an electric motor according to claim 3 or 4,
An attachment structure for a rotation detector for an electric motor, wherein the connection pins are arranged in a line in the circumferential direction. A mounting structure for a rotation detector for an electric motor according to any one of claims 2 to 5,
A mounting structure for a rotation detector for an electric motor, wherein the external lead wire drawn out from each connector portion is routed along the magnet coil and covered with a protective cover.

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