Motor housing

Abstract

The subject of the present invention is to improve the torsional rigidity of the motor housing of a rotating electric machine while promoting weight reduction. A motor housing, which accommodates a stator, a rotor opposite to the inner periphery of the stator, and a rotating shaft connected to the rotor, the motor housing having: a peripheral wall formed in a cylindrical shape, having a space inside for accommodating the stator and the rotating shaft; a flange portion formed at one end of the peripheral wall and connected to the outside; and a vibration-damping rib composed of a plurality of ribs, which is formed on the outer periphery of the peripheral wall and is formed between the position where the end of the stator intersects with the outer periphery of the peripheral wall on the radial extension line of the rotating shaft and the flange portion.

Description

Technical Field

[0001] The invention relates to a motor housing of a rotating electrical machine. Background Art

[0002] The motor housing of a rotating electric machine mounted on a vehicle is required to have both strength and weight reduction. To ensure strength and achieve weight reduction, a technique of forming ribs on the outer periphery of the motor housing has been disclosed (eg, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2009-232601 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] In a rotating electric machine for driving, since the torque generated is large and the electromagnetic excitation force generated is also large, the torsional rigidity of the motor housing must be increased. However, in the above-mentioned conventional examples, it is not possible to achieve both lightweighting of the motor housing and ensuring torsional rigidity.

[0008] If torsional rigidity cannot be ensured, vibrations due to electromagnetic excitation force are generated in the motor housing, and vibrations or noise increase particularly in the low rotation range, thereby impairing the quietness of the vehicle.

[0009] Therefore, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve the torsional rigidity of a motor case of a rotating electric machine while also promoting weight reduction.

[0010] Technical means of solving problems

[0011] The present invention is a motor housing that accommodates a stator, a rotor opposite to the inner circumference of the stator, and a rotating shaft connected to the rotor. The motor housing has: a peripheral wall that is formed in a cylindrical shape and has a space inside to accommodate the stator and the rotating shaft; a flange portion that is formed at one end of the peripheral wall and is connected to the outside; and a vibration-damping rib composed of a plurality of ribs that is formed on the outer circumference of the peripheral wall and is formed between the position where the end of the stator intersects with the outer circumference of the peripheral wall on the radial extension line of the rotating shaft and the flange portion.

[0012] Effects of the Invention

[0013] Therefore, the present invention forms vibration-damping ribs by crossing a plurality of ribs connecting the flange portion and the straight ribs on the outer periphery of the peripheral wall of the motor housing corresponding to the interval between the flange portion on the output side of the rotating motor and the end of the stator, thereby promoting lightweight while improving the torsional rigidity of the rotating motor and reducing torsional vibration.

[0014] Details of at least one implementation of the subject matter disclosed in this specification will be described in the accompanying drawings and the following description. Other features, aspects, and effects of the disclosed subject matter are explained through the following disclosure, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The embodiment of the present invention is shown in a front view of a motor case of a rotating electrical machine.

[0016] Figure 2 The embodiment of the present invention is shown in a half-sectional view of a motor case.

[0017] Figure 3 The embodiment of the present invention is shown in a perspective view of a motor case. DETAILED DESCRIPTION

[0018] Hereinafter, embodiments of the present invention will be described based on the drawings.

[0019] Figure 1 The motor case 1 is a front view of a motor housing of a rotary electric machine to illustrate an embodiment of the present invention. The motor housing 1 is formed of a cylindrical peripheral wall 10, and a circular flange portion 13 protruding toward the outer circumference is formed at the end of the peripheral wall 10 on the left side in the figure.

[0020] The flange 13 is the output side of the motor housing 1, and a speed reducer (or a mechanical element such as a transmission) not shown is installed. The flange 13 is formed at one axial end of the peripheral wall 10, and an open end 10A is formed at the other end, and a stator and a rotor (shaft 2 and rotor) are incorporated from the open end 10A.

[0021] Linear ribs 11-1 to 11-4 are formed at predetermined intervals on the outer periphery of the peripheral wall 10 and are parallel to the axis C1 of the shaft (rotation axis) 2. The linear ribs 11-1 to 11-4 protrude radially from the outer periphery of the peripheral wall 10 at a predetermined height with the axis C1 as the center. In the following description, when the individual linear ribs are not particularly specified, the symbol "11" is used with the "-" omitted. In addition, the symbols for other components are the same.

[0022] Annular ribs 12-1 to 12-3 are formed at predetermined intervals in the axial direction of the axis C1 on the outer periphery of the peripheral wall 10. The annular ribs 12 are formed at a predetermined height from the outer periphery of the peripheral wall 10 on a plane perpendicular to the axis C1.

[0023] Then, between the flange portion 13 and the annular rib 12-1 and between the linear rib 11-2 and the linear rib 11-3, vibration damping ribs 20-1 and 20-2 formed by crossing two linear ribs are formed. The vibration damping rib 20 protrudes from the outer periphery of the peripheral wall 10 to a predetermined height.

[0024] The vibration damping rib 20 - 1 (first rib) is formed at an angle greater than 0° and less than 90° relative to the axis C1 direction of the shaft 2 , and the vibration damping rib 20 - 2 (second rib) is formed at an angle greater than 90° and less than 180° relative to the axis C1 direction of the shaft 2 .

[0025] Furthermore, the vibration damping ribs 20 - 1 and 20 - 2 intersect each other at a predetermined angle, and connect the linear rib 11 - 2 , the linear rib 11 - 3 , and the flange portion 13 .

[0026] Figure 2 1 is a half-sectional view of the motor housing 1 of the rotating electric machine. A through hole 40 for inserting the shaft 2 is formed on the inner periphery of the flange portion 13 of the motor housing 1. Then, a planar inner peripheral surface 13A is formed on the back side of the flange portion 13 facing the inside of the peripheral wall 10. A cylindrical space is formed inside the peripheral wall 10 from the inner peripheral surface 13A to the open end 10A, which accommodates the stator 4, the shaft 2 and the rotor 3. In addition, a bearing not shown in the figure is installed in the through hole 40, which supports the shaft 2 so that it can rotate freely.

[0027] The cylindrical space inside the peripheral wall 10 is formed by spaces with different inner diameters. A space with a small inner diameter is formed from the inner peripheral surface 13A of the flange portion 13 to a predetermined distance L2 in the axial direction, and a space with a large inner diameter is formed from the predetermined distance L2 to the opening end 10A.

[0028] A step portion 21 is formed at a distance L2 from the inner peripheral surface 13A in the direction of the axis C1 as a boundary of the space with different inner diameters, and contacts the end 4A of the stator 4. The step portion 21 functions as a wall surface for positioning the end 4A of the stator 4.

[0029] Next, the vibration damping rib 20 formed on the outer periphery of the peripheral wall 10 is described. In addition, in the present embodiment, the outer peripheral surface 13B on the side of the opening end 10A of the flange portion 13 connected to the outer periphery of the peripheral wall 10 is located at the same position in the direction of the axis C1 as the inner peripheral surface 13A inside the peripheral wall 10. In addition, the outer peripheral surface 13B of the flange portion 13 is formed by a plane rising from the outer periphery of the peripheral wall 10.

[0030] The end of the flange portion 13 side of the vibration damping rib 20-1 is aligned with the linear rib 11-3 (see Figure 1) is connected to the linear rib 11-2 at a predetermined angle relative to the axis C1. The position of the vibration damping rib 20-1 in the direction of the axis C1 where the linear rib 11-2 is connected is set to be a predetermined distance L1 from the outer peripheral surface 13B of the flange portion 13.

[0031] Similarly, the end of the flange portion 13 side of the vibration damping rib 20-2 is connected to the linear rib 11-2, is inclined at a predetermined angle relative to the axis C1, and the other end is connected to the linear rib 11-3 (see Figure 1 The position in the axis C1 direction where the vibration damping rib 20 - 2 is connected to the linear rib 11 - 3 is set to be a predetermined distance L1 from the outer peripheral surface 13B of the flange portion 13 .

[0032] The damping ribs 20-1 and 20-2 are connected to the linear rib 11 at the same position L1 in the axis C1 direction. The distance L1 from the outer peripheral surface 13B of the flange portion 13 is set larger than the distance L2 from the inner peripheral surface 13A where the end portion 4A (step portion 21) of the stator 4 is arranged.

[0033] Here, the electromagnetic excitation force of the rotating electric machine is generated between the rotor 3 and the stator 4. The electromagnetic excitation force is transmitted to the motor case 1 via the stator 4.

[0034] The motor housing 1 of this embodiment determines the arrangement of the vibration-damping ribs 20 with an eye on the electromagnetic excitation force generated by the stator 4. That is, the vibration-damping ribs 20 are arranged in a manner that partially covers the outer periphery of the peripheral wall 10 in a section (distance L2) corresponding to the axis C1 direction from the flange portion 13 that connects the rotating electric machine and the reducer to the end portion 4A of the stator 4 that generates the electromagnetic excitation force.

[0035] In this embodiment, X-shaped vibration damping rib 20 formed by intersecting two linear ribs is formed from outer peripheral surface 13B on the outer peripheral side of peripheral wall 10 to a distance L1 , and covers end 4A of stator 4 inside peripheral wall 10 .

[0036] That is, the position in the direction of the axis C1 where the vibration-damping rib 20 is formed is set to a distance L1 greater than the distance L2 from the inner peripheral surface 13A of the flange portion 13 to the end 4A of the stator 4. In other words, the outer periphery of the peripheral wall 10 whose position in the direction of the axis C1 is consistent in the radial direction from the end 4A of the stator 4 is covered by the vibration-damping rib 20.

[0037] Here, when the peripheral wall 10 is manufactured by casting, the vibration damping ribs 20 are intermittently arranged in the circumferential direction of the peripheral wall 10 between the linear ribs 11 in consideration of the casting mold. In this embodiment, since the motor housing 1 is manufactured by casting, the vibration damping ribs 20 connected to the flange portion 13 are formed between the linear ribs 11-2 and 11-3, and the vibration damping ribs 20 are not formed between the linear ribs 11-1 and 11-2, but the present invention is not limited thereto. For example, when the motor housing 1 is manufactured by cutting, the vibration damping ribs 20 may be formed all around the adjacent linear ribs 11.

[0038] Figure 3 1 is a perspective view of a motor housing 1 of a rotating electrical machine. Figure 3 , the linear rib 11 of the motor housing 1 is shown deformed by the electromagnetic excitation force f. When the flange 13 of the motor housing 1 is connected to a speed reducer that transmits the output of the rotating electric machine, the electromagnetic excitation force f is generated when the rotor (rotor 3 and shaft 2) generates torque.

[0039] As shown by the arrow in the figure, the electromagnetic excitation force f acts on the side of the opening end 10A so as to twist the linear rib 11 downward in the figure. In this case, the vibration damping rib 20-1 suppresses the deformation of the linear rib 11-2 by supporting the linear rib 11-2 twisting downward due to the force in the compression direction by the end portion on the flange portion 13 side. On the other hand, the vibration damping rib 20-2 suppresses the deformation of the linear rib 11-3 by supporting the linear rib 11-3 twisting downward due to the force in the tension direction by the end portion on the flange portion 13 side.

[0040] In this way, by forming X-shaped vibration damping ribs 20 connecting the straight ribs 11 and the flange portion 13 in the outer periphery of the peripheral wall 10 in the section corresponding to the flange portion 13 to the end 4A of the stator 4, the torsional rigidity of the motor housing 1 can be improved while promoting weight reduction.

[0041] As described above, in this embodiment, the vibration damping rib 20 is formed by intersecting the connecting flange portion 13 and the two ribs of the linear ribs 11 - 2 and 11 - 3 , and the position where the vibration damping rib 20 is formed is set as the outer periphery of the peripheral wall 10 covering the flange portion 13 to the end 4A of the stator 4.

[0042] In other words, the plurality of ribs form the vibration damping rib 20 that supports the linear rib 11 from the position where the end 4A of the stator 4 intersects the peripheral wall 10 on the radial extension of the shaft 2 to the outer peripheral surface 13B of the flange portion 13 .

[0043] This makes it possible to improve the torsional rigidity while suppressing an increase in the weight of the motor case 1 , reduce vibrations caused by electromagnetic excitation force, and improve quietness of a vehicle equipped with the rotating electrical machine.

[0044] In the above embodiment, the position of the vibration-damping rib 20 is described with reference to the axis C1 of the shaft 2 , but the position may be based on the axis of the peripheral wall 10 .

[0045] In the above embodiment, the step portion 21 for axial positioning of the stator 4 is formed inside the peripheral wall 10, but the present invention is not limited thereto. For example, the inside of the peripheral wall 10 may be a space with a single inner diameter, and a partition plate or the like may be inserted on the inner peripheral surface 13A side.

[0046] Furthermore, in the above-described embodiment, an example in which the shape of the peripheral wall 10 is cylindrical is shown, but it may also be a cylindrical shape capable of accommodating the stator 4 and the rotor (the shaft 2 and the rotor 3).

[0047] In addition, in the above-mentioned embodiment, an example is shown in which the linear ribs 11 parallel to the axis C1 are formed on the outer periphery of the peripheral wall 10, but the invention is not limited thereto. There may be no ribs in the direction of the axis C1 on the outer periphery of the peripheral wall 10. In addition, ribs inclined relative to the axis C1 may be provided on the outer periphery of the peripheral wall 10.

[0048] <Conclusion>

[0049] As described above, the motor housing 1 of the above embodiment accommodates a stator (4); a rotor (3) which is opposite to the inner periphery of the stator (4); and a rotating shaft (2) which is connected to the rotor (3), and the motor housing has: a peripheral wall (10) which is formed in a cylindrical shape and has a space inside for accommodating the stator (4) and the rotating shaft (2); a flange portion (13) which is formed at one end of the peripheral wall (10) and connected to the outside; and a vibration-damping rib (20) composed of a plurality of ribs which is formed on the outer periphery of the peripheral wall (10) and is formed between the position where the end of the stator (4) intersects with the outer periphery of the peripheral wall on the extension line in the radial direction of the rotating shaft (2) and the flange portion (13).

[0050] By forming a vibration damping rib 20 composed of a plurality of ribs (20-1, 20-2) on the outer periphery of the peripheral wall 10 of the motor housing 1 and in a section corresponding to the flange portion 13 to the end portion 4A of the stator 4, the torsional rigidity of the motor housing 1 can be improved and the weight can be reduced.

[0051] In addition, the vibration-damping rib (20) is formed by crossing a plurality of linear ribs (20-1, 20-2). Thus, when electromagnetic excitation force is applied to the peripheral wall 10, for example, the vibration-damping rib 20-1 supports the force in the compression direction, and on the other hand, the vibration-damping rib 20-2 supports the force in the tension direction. The vibration-damping rib 20 suppresses torsional vibration, and can improve the torsional rigidity of the peripheral wall 10 from the outer periphery in the radial direction of the end 4A of the stator 4 to the flange portion 13. In addition, since the plurality of linear ribs (20-1, 20-2) are light in weight, it is possible to suppress an excessive increase in the weight of the motor housing 1.

[0052] In addition, a linear rib parallel to the axial direction of the rotating shaft (2) is formed on the outer periphery of the peripheral wall (10), and the vibration-damping rib (20) connects the linear rib and the flange portion (13).

[0053] Thus, when the electromagnetic excitation force is applied to the peripheral wall 10, for example, the vibration-damping rib 20-1 receives a force in a compression direction supported by the end portion on the flange portion 13 side, and the linear rib 11-2 twists downward, thereby suppressing the deformation of the linear rib 11-2. On the other hand, the vibration-damping rib 20-2 receives a force in a tension direction supported by the end portion on the flange portion 13 side, and the linear rib 11-3 twists downward, thereby suppressing the deformation of the linear rib 11-3. In this way, the vibration-damping rib 20 can suppress torsional vibration and improve the torsional rigidity of the peripheral wall 10 from the outer periphery in the radial direction of the end portion 4A of the stator 4 to the flange portion 13.

[0054] In addition, the plurality of ribs include a first rib and a second rib, wherein the first rib is formed at an angle greater than 0° and less than 90° relative to the axial direction of the rotating shaft (2), and the second rib is formed at an angle greater than 90° and less than 180° relative to the axial direction of the rotating shaft (2).

[0055] Thus, by forming X-shaped vibration damping ribs 20 connecting the linear ribs 11 and the flange 13 in the section from the flange 13 to the end 4A of the stator 4 on the outer periphery of the peripheral wall 10, it is possible to improve the torsional rigidity of the motor housing 1 and promote weight reduction.

[0056] Furthermore, by crossing the vibration-damping rib 20-1 and the vibration-damping rib 20-2, when the vibration-damping rib 20-1 is subjected to a compressive load and the load 20-2 is subjected to a tensile load, the load is dispersed from the intersection position with the vibration-damping rib 20-1, thereby reducing the deformation caused by the tensile force of the vibration-damping rib 20-2 and reducing the torsional vibration.

[0057] In addition, the present invention is not limited to the above-mentioned embodiments, but also includes various modified examples. For example, the above-mentioned embodiments are described in detail to explain the present invention in an easy-to-understand manner, and are not necessarily limited to having all the described structures. In addition, a part of the structure of a certain embodiment can be replaced with other embodiments, and in addition, the structure of other embodiments can be added to the structure of a certain embodiment. In addition, with respect to a part of the structure of each embodiment, each of the addition, deletion or replacement of other structures can be applied alone or in combination.

[0058] Explanation of symbols

[0059] 1 Motor housing

[0060] 2 Axis

[0061] 3 Rotor

[0062] 4 Stator

[0063] 4A End

[0064] 10. Wall

[0065] 11-1~11-4 Axial rib

[0066] 12-1 to 12-3 Circumferential ribs

[0067] 13 Flange

[0068] 13A Inner Surface

[0069] 20-1, 20-2 Vibration-damping ribs

[0070] 21 Step section.

Claims

1. A motor housing, which accommodates a stator, a rotor facing the inner periphery of the stator, and a rotating shaft coupled to the rotor, the motor housing being characterized by having: A peripheral wall formed in a cylindrical shape and having a space inside for accommodating the stator and the rotating shaft; a flange portion formed at one end of the peripheral wall and coupled to the outside; and A vibration-damping rib composed of a plurality of ribs is formed on the outer periphery of the peripheral wall and is formed between the end of the stator and the position where the outer periphery of the peripheral wall intersects on the radial extension line of the rotating shaft and the flange portion. The vibration-damping rib is formed by crossing a plurality of linear ribs. At least two straight ribs parallel to the axial direction of the rotating shaft are formed on the outer periphery of the peripheral wall. The vibration-damping rib is disposed between the two linear ribs and connects the two linear ribs and the flange portion.

2. The motor housing according to claim 1, characterized in that: The plurality of ribs include a first rib and a second rib, the first rib being formed at an angle greater than 0° and less than 90° relative to the axial direction of the rotating shaft, and the second rib being formed at an angle greater than 90° and less than 180° relative to the axial direction of the rotating shaft.

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