JP4657249B2 - Rotating electric machine - Google Patents

Description

  The present invention relates to a rotating electrical machine, and more particularly to a rotating electrical machine having an improved frame structure.

  As a conventional device related to the frame structure of a rotating electrical machine, in order to prevent the occurrence of vibration and noise due to armature swinging, the armature is pivoted with a bearing press-fitted into the center of the bottom of the yoke and a bearing press-fitted with a bracket. In a rotating electrical machine to be supported, there is a technology in which a thin part with a thin plate thickness is formed by press working around a support part for press-fitting a bearing, and a step part is formed between the thick part with a relatively large thickness. It has been proposed (see, for example, Patent Document 1).

JP 2005-73319 A (summary column, FIG. 1)

  According to the rotating electrical machine proposed by Patent Document 1, the strength of the bottom portion is increased by press hardening the strength around the support portion, and the effect of preventing the generation of vibration and noise due to armature swinging is obtained. In addition, by making it thin, there is an effect that the space in the frame can be increased as much as the plate thickness decreases.

  However, in the frame structure configured as described above, the configuration of the press mold for forming the stepped portion around the bearing support portion is complicated, leading to deterioration in productivity and an increase in mold manufacturing cost. Become. Moreover, since the corner | angular part which connects a flame | frame circular pipe part and a bottom face is a right angle, a flame | frame can vibrate to both a rotor side and the other side of a rotor, and there exists a problem which tends to lead to noise deterioration.

  The present invention was made to solve the above-described problems, and the thickness of the bottom surface of the frame is kept uniform, the press mold configuration is simplified, the productivity is deteriorated, and the mold manufacturing cost is increased. It is an object of the present invention to provide a frame-shaped rotating electrical machine that can suppress vibration and noise without increasing the overall length of the rotating electrical machine.

A rotating electrical machine according to the present invention is a rotating electrical machine having a frame having a bottomed cylindrical shape and having a bearing support portion on a bottom surface portion, and the bottomed cylindrical frame is formed by pressing a steel plate. , it is characterized in that the inner angle of the corner portion connecting the circular tube portion and the bottom portion of the stator or the magnet is fixed is less than 70 degrees than 90 degrees.

  According to the present invention, a frame shape that simplifies the press mold configuration, suppresses deterioration in productivity, suppresses increase in mold manufacturing cost, and can take measures against vibration and noise without increasing the overall length of the rotating electrical machine. A rotating electrical machine can be provided.

  Exemplary embodiments of a rotating electrical machine according to the present invention will be explained below in detail with reference to the accompanying drawings.

Embodiment 1 FIG.
1 is a cross-sectional view of a rotary electric machine, for example, a brushless motor, according to Embodiment 1 of the present invention, and FIG. 2 is a frame shape view.
In FIG. 1, a brushless motor 1 includes a frame 2 having a bottomed cylindrical shape, and a stator 4 having a coil winding 3 applied to the inner periphery of a circular pipe portion 2a of the frame 2 is fixed by press-fitting or the like. A rotor 5 is disposed through a predetermined gap from the inner peripheral surface of the stator 4. The rotor 5 has a magnet 7 fixed to the shaft 6 by bonding or the like. The rotor 5 is supported by a bearing 9 held by a bearing case portion 8 provided on the frame 2 and a bearing case portion 11 provided on the housing 10. The bearing 12 is held so as to be rotatable. The frame 2 is formed by pressing a steel plate.

  FIG. 2 is a frame shape diagram, and the frame 2 is configured so that the inner angle of the corner portion connecting the circular tube portion 2a and the bottom surface portion 2b is less than 90 degrees.

  The rotating electrical machine 1 according to Embodiment 1 is configured as described above. When this rotating electrical machine 1 is driven, the vibration of the rotor 5 such as vibration propagation from the mounting device side transmitted from the tip 5 a of the shaft 6 of the rotor 5, magnetic vibration of the rotor 5 itself, or rotation unbalance of the rotor 5, etc. As a result, vibration is generated in the bottom surface 2b of the frame 2. However, since the inner angle of the corner portion connecting the circular tube portion 2a and the bottom surface portion 2b of the frame 2 is configured to be less than 90 degrees, the load for displacing the bottom surface portion 2b to the opposite side of the rotor 5 increases. The vibration of the bottom surface 2b due to the excitation force to the opposite side of the rotor 5 is suppressed, and the effect of reducing vibration and noise can be brought about.

  Further, the shape of the frame 2 of the rotating electrical machine 1 according to the first embodiment is different from that of the conventional structure in which the angle connecting the circular tube portion 2a and the bottom surface portion 2b is 90 degrees. It is only an angle connecting the part 2a and the bottom part 2b, and can be realized without changing the press die configuration and additional steps when manufacturing, and without causing deterioration in productivity and increase in die manufacturing cost. , Noise reduction effect can be brought about.

  As another effect, in the brushless motor as shown in FIG. 1, the end position of the coil end 13 of the stator 4 to which the coil winding 3 is applied on the frame bottom surface portion 2 b side is the frame bottom surface portion of the magnet 7. Since it is located on the frame bottom surface portion 2b side from the end portion position on the 2b side, the internal space of the brushless motor 1 is made effective by configuring the inner angle of the angle connecting the circular tube portion 2a and the bottom surface portion 2b to less than 90 degrees. Therefore, it is possible to bring about an effect of reducing vibration and noise without increasing the overall length.

  Further, the inner angle of the angle connecting the circular tube portion 2a and the bottom surface portion 2b of the frame 2 is desirably less than 90 degrees and 70 degrees or more, and in the case of less than 70 degrees, the end position of the coil end 13 on the frame bottom surface portion 2b side. Since the space of the bottom surface portion 2b of the frame 2 is increased, there is a disadvantage that the entire length becomes longer.

Embodiment 2. FIG.
3 is a cross-sectional view of a rotary electric machine, for example, a brush motor, according to Embodiment 2 of the present invention, and FIG. 4 is a frame shape view.
In FIG. 3, the brushed motor 30 includes a frame 31 having a bottomed cylindrical shape, and a magnet 32 is fixed to the inner periphery of a circular pipe portion 31 a of the frame 31 by a press fit or the like via a holder 33. In addition, an armature 34 is disposed through a predetermined gap from the inner peripheral surface of the magnet 32. The armature 34 is formed by applying a coil winding 36 to a plurality of teeth fixed to a shaft 35, a bearing 38 held by a bearing case portion 37 provided on the frame 31, and a bearing provided on a housing 39. A bearing 41 held by the case portion 40 is rotatably supported. The frame 31 is formed by pressing a steel plate.

FIG. 4 is a frame shape diagram, and the frame 31 is configured such that the inner angle of the corner portion connecting the circular pipe portion 31a and the bottom surface portion 31b exceeds 90 degrees.

  The rotating electrical machine 30 according to the second embodiment is configured as described above. When the rotating electrical machine 30 is driven, vibration of the armature 34 such as vibration propagation from the attachment device side transmitted from the tip 34a of the shaft 35 of the armature 34, magnetic vibration of the armature 34 itself, or rotation unbalance of the armature 34, etc. As a result, vibration of the frame bottom surface portion 31b occurs. However, since the inner angle of the corner portion connecting the circular pipe portion 31a and the bottom surface portion 31b of the frame 31 is configured to exceed 90 degrees, the load for displacing the bottom surface portion 31b toward the armature 34 increases, and the armature Vibration to the armature 34 side of the bottom surface portion 31b due to the excitation force is suppressed, and an effect of reducing vibration and noise can be brought about.

  The shape of the frame 31 of the rotating electrical machine 30 according to the second embodiment is the same as that of the first embodiment, with respect to the frame of the conventional structure in which the angle connecting the circular pipe portion 31a and the bottom surface portion 31b is 90 degrees. The only difference is the angle connecting the circular pipe portion 31a and the bottom surface portion 31b, which can be realized without changing the press die configuration during manufacturing and without additional steps, resulting in reduced productivity and increased die manufacturing cost. The effect of reducing vibration and noise can be brought about without causing it.

As another effect, in the brushed motor 30 as shown in FIG. 3, the end position on the frame bottom surface portion 31 b side of the coil end 42 of the coil winding 36 is the end portion on the frame bottom surface portion 31 b side of the magnet 32. Since it is located on the frame bottom surface portion 31b side from the position, the internal angle of the angle connecting the circular tube portion 31a and the bottom surface portion 31b exceeds 90 degrees, so that the space inside the brushed motor 30 is effectively used. This can reduce the vibration and noise without increasing the overall length.

  Further, the inner angle of the angle connecting the circular pipe portion 31a and the bottom surface portion 31b of the frame 31 is preferably more than 90 degrees and not more than 110 degrees, and when it is 110 degrees or more, the coil end 42 side of the frame bottom surface portion 31b Since the space between the end portion position and the bottom surface portion 31b of the frame 31 is increased, there is a disadvantage that the entire length becomes longer.

Embodiment 3 FIG.
Next, a third embodiment will be described. FIG. 5 is a frame shape diagram of a rotating electrical machine according to Embodiment 3, for example, a brushless motor.
If there are no restrictions on the overall length of the brushless motor, the brushless motor 1 shown in FIG. 1 has a frame 50 having the shape shown in FIG. 5, that is, the inner angle of the angle connecting the circular pipe portion 50a and the bottom surface portion 50b is 90 degrees. Even if the frame 50 having an angle exceeding the limit is incorporated, it is possible to bring about an effect of reducing vibration and noise without causing deterioration in productivity and an increase in mold manufacturing cost.

Embodiment 4 FIG.
Next, a fourth embodiment will be described. FIG. 6 is a frame shape diagram of a rotating electrical machine according to the fourth embodiment, for example, a motor with a brush.
If there is no mounting restriction on the overall length of the brushed motor, the inner angle of the angle connecting the frame 60 having the shape shown in FIG. 6, that is, the circular pipe portion 60a and the bottom surface portion 60b, to the brushed motor 30 of FIG. 3 is 90 degrees. Even if the frame 60 that is less than the above is incorporated, it is possible to bring about an effect of reducing vibration and noise without causing deterioration in productivity and increase in mold manufacturing cost.

  The rotating electrical machine according to the present invention can be used for a rotating electrical machine that drives an electrohydraulic power steering apparatus including a hydraulic pump.

It is sectional drawing of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a frame shape figure of the rotary electric machine shown in FIG. It is sectional drawing of the rotary electric machine which concerns on Embodiment 2 of this invention. It is a frame shape figure of the rotary electric machine shown in FIG. FIG. 6 is a frame shape diagram of a rotating electrical machine according to a third embodiment. FIG. 6 is a frame shape diagram of a rotating electrical machine according to a fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Brushless motor 2, 31, 50, 60 Frame 2a, 31a, 50a, 60a Round pipe part 2b, 31b, 50b, 60b Bottom face part 3, 36 Coil winding 4 Stator 5 Rotor 6, 35 Shaft 7, 32 Magnet 8, 11, 37, 40 Bearing case part 9, 12, 38, 41 Bearing 10, 39 Housing 13, 42 Coil end 30 Brushed motor 33 Holder 34 Armature

Claims (1)

A rotating electric machine having a bottomed cylindrical shape and having a frame with a bearing support on the bottom surface, wherein the bottomed cylindrical frame is formed by pressing a steel plate, and a stator or magnet is fixed to the rotating electric machine. rotating electric machine, wherein the internal angle of the circular pipe portion and the corner portion connecting the bottom portion is less than 70 degrees than 90 degrees that.

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