JP2021175303A - Rotary electric machine - Google Patents

Abstract

To solve the problem in which, in a rotary electric machine connected to an external device via a transmission belt, when excessive input torque is applied to a pulley, rotational misalignment occurs between parts with low axial force, causing a nut to loosen, leading to the pulley and nut falling off.SOLUTION: A rotary electric machine includes a pulley connected to a transmission belt, a rotary shaft having a flange extending in the radial direction, and a nut that tightens an inner ring of a bearing of the rotary shaft and a boss part of the pulley, which are passed through the rotary shaft between the flange and the nut, by means of a bolt part provided at the end of the rotary shaft. The outer diameter dimension of a seating surface of the nut is within ±10% of the outer diameter dimension of the boss part of the pulley.SELECTED DRAWING: Figure 1

Description

The present application relates to a rotary electric machine.

In recent years, rotary electric machines mounted on vehicles such as automobiles have been used not only for transmitting power in one direction such as auxiliary power or generators, but also for bidirectional power transmission with an external device. It has increased. In such applications, phenomena such as sudden torque fluctuations may occur. Therefore, there has been a problem that a rotation deviation occurs only by the method of fixing the pulley and the rotating shaft, which has been conventionally performed in a rotating electric machine using a transmission belt.

The structure including the pulley of the rotary electric machine is shown in Patent Document 1. The rotary electric machine of Patent Document 1 is integrally formed with a pulley, a bearing component, and a rotary shaft in order from the transmission belt side as parts provided on the rotary shaft together with a nut on the transmission belt side, which is one free end of the rotary shaft. It has a collar. It has a structure in which a pulley and a bearing component, which are parts to be fastened, are integrally fastened to a flange portion of the rotating shaft by a screw portion and a nut provided at the end of the rotating shaft.

French Patent No. 3054742 (Fig. 1)

In the rotary electric machine of Patent Document 1, the outer diameter of the seat surface of the nut for tightening the fastened component at the end of the rotating shaft is larger than the seat surface diameter of the fastened component provided on the rotating shaft. Therefore, the pulley bends at the portion in contact with the seat surface of the nut due to the tightening of the nut, so that a sufficient axial force cannot be obtained from the tightening torque of the nut. Therefore, there is a problem that the tightening torque when the nut is fastened to the rotating shaft cannot be used well as the axial force which is the pressing force in the axial direction.

The axial force, which is the axial pressing force applied to the rotating shaft due to the tightening of the nut, is not sufficiently transmitted to the pulleys to be fastened, the bearing parts, and the flange portion integrally formed with the rotating shaft. The pulley rotates integrally with the rotating shaft by the frictional force generated by this axial force. Therefore, when an excessive input torque is applied to the pulley, there is a problem that rotational deviation occurs between parts having a low axial force, the nut loosens, and the pulley and the nut fall off.

An object of the present application is to obtain a rotary electric machine having a structure for preventing rotation between parts to be fastened and rotation deviation of a pulley by efficiently using the tightening torque of a nut as an axial force.

The rotary electric machine according to the present application is a rotary electric machine connected to an external device via a transmission belt, and has a pulley connected to the transmission belt, a rotary shaft having a flange portion extending in the radial direction, and the flange portion. The inner ring of the bearing of the rotary shaft and the boss portion of the pulley, which are passed through the rotary shaft, are fastened by a bolt portion provided at the end of the rotary shaft. The bearing surface outer diameter dimension of the nut is set to be within ± 10% of the outer diameter dimension of the boss portion of the pulley.

In the rotary electric machine of the present application, the seat surface outer diameter dimension of the nut is set to be within ± 10% of the outer diameter dimension of the boss portion of the pulley, so that the tightening torque of the nut can be efficiently adjusted. It can be used as a force and can prevent rotation between the parts to be fastened and rotation deviation of the pulley.

It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 1. FIG. It is an enlarged cross-sectional view of the rotating shaft of the rotary electric machine which concerns on Embodiments 1 and 2 and the peripheral part thereof. FIG. 5 is an enlarged cross-sectional view of an end portion of a rotary shaft of a rotary electric machine according to a third embodiment and a peripheral portion thereof. FIG. 5 is an enlarged cross-sectional view of an end portion of a rotary shaft of a rotary electric machine according to a third embodiment and a peripheral portion thereof. FIG. 5 is an enlarged cross-sectional view of an end portion of a rotary shaft of a rotary electric machine and a peripheral portion thereof according to the fourth embodiment. FIG. 5 is an enlarged cross-sectional view of an end portion of a rotary shaft of a rotary electric machine and a peripheral portion thereof according to the fourth embodiment. FIG. 5 is an enlarged cross-sectional view of an end portion of a rotary shaft of a rotary electric machine and a peripheral portion thereof according to the fourth embodiment.

Embodiment 1.
FIG. 1 shows a cross-sectional view of a rotary electric machine according to the first embodiment. The rotary electric machine according to the first embodiment is a rotary electric machine integrated with a control device. A generator motor mounted on a vehicle and used for driving assistance and power generation will be described as an example. The rotary electric machine 1 with an integrated control device includes a rotary electric machine main body 1a and a control device 1b integrally. The rotary electric machine main body 1a includes a field iron core 2, a stator 3, a front case 4, a rear case 5, a front bearing 7, a rear bearing 8, cooling fans 20, 21 and a rotary shaft 22.

A stator winding 3a is wound around the stator 3. A field iron core 2 is provided on the inner peripheral side of the stator 3. The field iron core 2 is configured by winding a field winding 2a around the iron core 2b. A front case 4 and a rear case 5 are arranged at both ends of the stator 3 in the axial direction. The front case 4 and the rear case 5 are provided as a pair of cases so as to support the stator 3.

A pulley 12 is provided on the rotating shaft 22 protruding from the front case 4 at the end 25 which is one end side of the rotating shaft 22. The pulley 12 is fastened to the rotating shaft 22 by a bolt portion 25a, which is a male screw formed on the end portion 25 of the rotating shaft 22, and a nut 14 attached to the bolt portion 25a. Therefore, the pulley 12 is mounted on the end portion 25 of the rotating shaft 22 so as to be rotatable integrally with the rotating shaft 22.

Further, a rotation position detection sensor 6 for detecting the rotation state of the field iron core 2 is provided at the other end portion 26 of the rotation shaft 22 protruding from the rear case 5. Further, at the end portion 26 of the rotating shaft 22, a pair of slip rings 13 for supplying a current to the field winding 2a are provided outside the rotating position detection sensor 6. A pair of brushes 17 that are in sliding contact with the slip ring 13 are provided on the outside of the rear case 5. The brush 17 is held by the brush holder 16.

Next, the control device 1b will be described. The control device 1b includes a power circuit unit, a field circuit unit, and a control circuit unit (not shown in FIG. 1). The power circuit unit is electrically connected to the stator winding 3a. The field circuit unit is electrically connected to the field winding 2a. The control circuit unit controls the power circuit unit and the field circuit unit.

Next, the operation of the rotary electric machine 1 integrated with the control device will be described with reference to FIG. The rotary electric machine 1 with an integrated control device has a function of an electric motor as an auxiliary for driving a vehicle and a function of a generator for power generation. First, a case where the rotary electric machine 1 integrated with the control device functions as an electric motor will be described. The DC power supplied to the power circuit unit from an external battery (not shown) is converted into a three-phase alternating current by the on / off control of the power circuit unit and supplied to the stator winding 3a.

Further, the DC power supplied from the external battery is adjusted by the field circuit unit and supplied to the field winding 2a. By this supply, a rotating magnetic field is generated around the field winding 2a, and as a result, the field iron core 2 rotates together with the rotating shaft 22. The rotation of the rotating shaft 22 is transmitted from the pulley 12 to the engine via a transmission belt (not shown). Further, the control circuit unit controls the power circuit unit and the field circuit unit based on information from an external device (not shown) and the rotation position detection sensor 6.

Next, a case where the rotary electric machine 1 integrated with the control device functions as a generator will be described. When the engine rotates, the rotational force of the engine is transmitted to the rotating shaft 22 via the transmission belt and the pulley 12. As a result, the field iron core 2 rotates, and the three-phase AC power is excited in the stator winding 3a. Then, the control circuit unit controls the on / off of the power circuit unit, and converts the three-phase AC power excited by the stator winding 3a into DC power. The converted DC power is supplied to an external battery and charged.

Next, the structure at the end 25 of the rotating shaft 22 will be described. A collar portion 23 is provided on the rotating shaft 22. A part to be fastened is provided between the flange portion 23 and the nut 14. The parts to be fastened include the inner ring 7a of the front bearing 7 and the boss portion 12a of the pulley 12, which are fastened by tightening the nut 14.

FIG. 2 is an enlarged cross-sectional view of the rotary shaft 22 of the rotary electric machine 1 according to the first embodiment and its peripheral portion. Let X be the outer diameter of the seat surface of the nut 14, and let Y be the outer diameter of the boss portion 12a of the pulley 12. Y is configured within the outer diameter dimension equal to or ± 10% of X. As a result of aligning the external dimensions in this way, the tightening torque of the nut 14 can be efficiently used as the axial force. By pressing the boss portion 12a of the pulley 12 and the inner ring 7a of the front bearing 7 with this axial force, it is possible to prevent the rotation deviation of the pulley 12.

A tolerance of ± 10% is provided for the relationship between X, which is the outer diameter dimension of the seat surface of the nut 14, and Y, which is the outer diameter dimension of the boss portion 12a of the pulley 12. The pressing force generated by the axial force does not change even if a difference of that degree is allowed in terms of dimensions, and the axial force can be used efficiently.

As described above, the pulley 12 connected to the transmission belt, the rotating shaft 22 having the flange portion 23 overhanging in the radial direction, and the front bearing of the rotating shaft 22 passed through the rotating shaft 22 between the flange portion 23. X is provided with a nut 14 for tightening the inner ring 7a of 7 and the boss portion 12a of the pulley 12 by a bolt portion 25a provided at the end portion 25 of the rotating shaft 22, which is the bearing surface outer diameter dimension of the nut 14. Is set to be within ± 10% of Y, which is the outer diameter dimension of the boss portion 12a of the pulley 12, so that the tightening torque of the nut 14 can be efficiently used as the axial force, and the parts to be fastened. It is possible to prevent rotation between the pulleys and rotation deviation of the pulley 12.

Embodiment 2.
In the second embodiment, the point of preventing the rotation deviation of the pulley 12 by devising the outer diameter dimension of the inner ring 7a of the front bearing 7 will be described. In FIG. 2, the outer diameter dimension of the inner ring 7a of the front bearing 7 is Z. In addition to making it within ± 10% of X, which is the outer diameter of the seat surface of the nut 14 shown in the first embodiment, and Y, which is the outer diameter of the boss portion 12a of the pulley 12. Z is equal to or ± 10% of X, which is the outer diameter of the seat surface of the nut 14.

As a result of aligning the external dimensions in this way, the axial force generated by tightening the nut 14 is efficiently transmitted as a pressing force between the boss portion 12a of the pulley 12 and the inner ring 7a of the front bearing 7. Further, the axial force transmitted from the boss portion 12a of the pulley 12 is efficiently transmitted as a pressing force between the inner ring 7a of the front bearing 7 and the flange portion 23 of the rotating shaft 22, and the rotation between the parts to be fastened. And the effect of preventing the rotation deviation of the pulley 12 can be improved.

Embodiment 3.
In the third embodiment, it will be described that the effect of preventing the rotation deviation of the pulley 12 is improved by devising the fixing method between the pulley 12 and the rotating shaft 22. FIG. 3A is an enlarged cross-sectional view of the rotary shaft 22 of the rotary electric machine 1 according to the third embodiment and its peripheral portion. Further, FIG. 3B is a cross-sectional view taken along the line AA in FIG. 3A. A key groove 22a is provided in the axial direction on the outer peripheral surface of the end portion 25 of the rotating shaft 22 according to the third embodiment. The key 27 is provided so as to be fitted into the key groove 22a of the rotating shaft 22 and the key groove 12b provided in the axial direction on the inner peripheral surface of the boss portion 12a of the pulley 12.

By adopting a structure in which the key 27 is fitted into the key groove 22a of the rotating shaft 22 and the key groove 12b of the pulley 12, it is possible to prevent the pulley 12 and the rotating shaft 22 from rotating due to the shearing force acting on the key 27. ..

Embodiment 4.
In the fourth embodiment, it is described that the structure is different from that of the third embodiment, and the effect of preventing the rotation deviation of the pulley 12 is improved by devising the fixing method between the pulley 12 and the rotating shaft 22. do. FIG. 4A is an enlarged cross-sectional view of the rotary shaft 22 of the rotary electric machine 1 according to the fourth embodiment and its peripheral portion. Further, FIG. 4B is a cross-sectional view taken along the line BB in FIG. 4B. On the outer peripheral surface of the rotating shaft 22 according to the fourth embodiment, a spline portion 12c provided with a tooth-shaped groove portion in the axial direction is formed on the inner peripheral surface of the boss portion 12a of the pulley 12. A spline portion 22b having a tooth-shaped groove in the axial direction is also formed on the outer peripheral surface of the rotating shaft 22 facing the inner peripheral surface of the boss portion 12a of the pulley 12. The spline portion 22b of the rotating shaft 22 and the spline portion 12c of the pulley 12 are provided so as to be spline-fitted to each other.

By adopting a spline fitting structure in which the spline portion 22b of the rotating shaft 22 and the spline portion 12c of the pulley 12 are fitted, it is possible to prevent the rotation shaft 22 and the pulley 12 from rotating.

Embodiment 5.
In the fifth embodiment, the structure is different from that of the third and fourth embodiments, and the effect of preventing the rotation deviation of the pulley 12 is improved by devising the fixing method between the pulley 12 and the rotating shaft 22. Will be described. On the outer peripheral surface of the rotating shaft 22 according to the fifth embodiment, a spline portion 22b having a tooth-shaped groove portion provided in the axial direction at a position facing the inner peripheral surface of the boss portion 12a of the pulley 12 is formed. .. On the other hand, no spline is formed on the inner peripheral surface of the pulley 12, and it is in a cylindrical state. The boss portion 12a of the pulley 12 is press-fitted to the spline portion 22b of the rotating shaft 22.

By adopting a structure in which the pulley 12 is press-fitted into the spline portion 22b of the rotating shaft 22, the fastening force between the rotating shaft 22 and the pulley 12 can be improved, and the rotation deviation between the rotating shaft 22 and the pulley 12 can be prevented. be able to.

Embodiment 6.
In the sixth embodiment, the structure is different from that of the third to fifth embodiments, and the effect of preventing the rotation deviation of the pulley 12 is improved by devising the fixing method between the pulley 12 and the rotating shaft 22. Will be described. FIG. 5 is an enlarged cross-sectional view of the rotary shaft 22 of the rotary electric machine 1 according to the sixth embodiment and its peripheral portion. With respect to Da, which is the outer diameter dimension of the rotating shaft 22 according to the sixth embodiment, Db, which is the inner diameter dimension of the boss portion 12a of the pulley 12, has a relationship of Da> Db, and the pulley with respect to the rotating shaft 22. 12 is press-fitted.

By adopting a structure in which the pulley 12 is press-fitted to the rotating shaft 22, the fastening force between the rotating shaft 22 and the pulley 12 can be improved, and the rotation deviation between the rotating shaft 22 and the pulley 12 can be prevented. Can be done.

Embodiment 7.
In the seventh embodiment, it will be described that the effect of preventing the rotation deviation of the pulley 12 is improved by devising the fixing method between the nut 14 and the rotating shaft 22. The rotating shaft 22 and the nut 14 are fixed by welding to the nut 14 fastened to the rotating shaft 22 according to the seventh embodiment.

By forming the nut 14 fastened to the rotating shaft 22 by welding, the fastening force between the rotating shaft 22 and the nut 14 can be improved. As a result, the nut 14 can be prevented from loosening, and the rotation shaft 22 and the pulley 12 can be prevented from being rotated.

Embodiment 8.
In the eighth embodiment, it will be described that the effect of preventing the rotation deviation of the pulley 12 is improved by devising the fixing method between the nut 14 and the rotating shaft 22. The rotating shaft 22 and the nut 14 are adhesively fixed to the nut 14 fastened to the rotating shaft 22 according to the eighth embodiment with an adhesive.

By adopting a structure in which the nut 14 fastened to the rotating shaft 22 is fixed with an adhesive, the fastening force between the rotating shaft 22 and the nut 14 can be improved. As a result, the nut 14 can be prevented from loosening, and the rotation shaft 22 and the pulley 12 can be prevented from being rotated.

In the above-described embodiment, the rotary electric machine 1 is a generator motor using a transmission belt as an example, but it can also be applied to an alternator or the like.

Although the present application describes various exemplary embodiments and examples, the various features, embodiments, and functions described in one or more embodiments are applications of a particular embodiment. It is not limited to, but can be applied to embodiments alone or in various combinations. Therefore, innumerable variations not illustrated are envisioned within the scope of the techniques disclosed herein. For example, it is assumed that at least one component is modified, added or omitted, and further, at least one component is extracted and combined with the components of other embodiments.

1 rotary electric machine, 1a rotary electric machine main body, 1b controller, 2 field iron core, 2a field winding, 2b iron core, 3 stator, 3a stator winding, 4 front case, 5 rear case, 6 rotation position detection sensor, 7 front bearing, 7a inner ring, 8 rear bearing, 12 pulley, 12a boss part, 12b keyway, 12c spline part, 13 slip ring, 14 nut, 16 brush holder, 17 brush, 20 cooling fan, 21 cooling fan, 22 rotations Shaft, 22a keyway, 22b spline, 23 flanges, 25 ends, 25a bolts, 26 ends, 27 keys.

The rotary electric machine according to the present application is a rotary electric machine connected to an external device via a transmission belt, and has a pulley connected to the transmission belt, a rotary shaft having a flange portion extending in the radial direction, and the flange portion. and a said inner ring of the bearing of the rotary shaft is passed through the rotary shaft and the boss portion of the pulley, it is clamped by a bolt portion provided at an end portion of the rotary shaft nut between the flange portion is provided integrally with the rotary shaft, the bearing surface outside diameter dimension of said nut, Ri range der of ± 10% of the outer diameter of the boss portion of the pulley, said by tightening torque of the nut The axial force generated on the rotating shaft regulates the rotational deviation of the pulley from the rotating shaft .

Claims (8)

A rotary electric machine connected to an external device via a transmission belt.
The pulley connected to the transmission belt and
A rotating shaft with a collar overhanging in the radial direction,
A nut that fastens the inner ring of the bearing of the rotating shaft and the boss portion of the pulley that are passed through the rotating shaft between the flange portion and the boss portion of the pulley by a bolt portion provided at the end portion of the rotating shaft. Prepare,
A rotary electric machine characterized in that the seat surface outer diameter dimension of the nut is within ± 10% of the outer diameter dimension of the boss portion of the pulley. The rotary electric machine according to claim 1, wherein the seat surface outer diameter dimension of the nut is within ± 10% of the outer diameter dimension of the inner ring of the bearing. A key groove is provided in the axial direction at the end of the rotating shaft, and the key is inserted between the key groove and the key groove provided in the axial direction of the inner peripheral surface of the boss portion of the pulley. The rotary electric machine according to claim 1 or 2. A tooth-shaped groove is provided on the outer peripheral surface of the end of the rotating shaft in the axial direction, and a spline is fitted between the outer peripheral surface and the tooth-shaped groove provided in the axial direction of the inner peripheral surface of the boss portion of the pulley. The rotary electric machine according to claim 1 or 2, wherein the alignment is provided. Claim 1 or claim 2 is characterized in that a tooth-shaped groove is provided on the outer peripheral surface of the end of the rotating shaft in the axial direction, and the pulley is press-fitted into the tooth-shaped groove. The rotary electric machine described in. The rotary electric machine according to claim 1 or 2, wherein the inner peripheral surface of the pulley is press-fitted to the outer peripheral surface of the end portion of the rotating shaft. The rotary electric machine according to any one of claims 1 to 6, wherein the nut is welded to an end portion of the rotary shaft. The rotary electric machine according to any one of claims 1 to 6, wherein the nut is adhesively fixed to the end of the rotating shaft with an adhesive.

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