Motor support structure

Abstract

To provide a motor support structure capable of suppressing transmission of noise and vibration.SOLUTION: A motor support structure 10 includes a motor frame 16, a motor unit 12 arranged below the motor frame 16, and a pair of support arms 20 extending downward from the motor frame 16, connected to both ends in a motor shaft direction, and supporting the motor unit 12. Upper end portions of the pair of support arms 20 are respectively supported by the motor frame 16 via a pair of elastic support bodies 50. Lower portions of the pair of support arms 20 are fixed to at least a lower 12LW of the motor unit 12.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a motor support structure. [Background technology]

[0002] In recent years, efforts to provide access to sustainable transport systems that take into consideration vulnerable transport participants such as the elderly, people with disabilities, and children have been gaining momentum. To achieve this, research and development is being conducted to further improve road safety and convenience through development of crash safety performance.

[0003] Japanese Patent Publication No. 6455654 discloses a motor unit support structure for an electric vehicle. The motor unit support structure includes a motor unit and a motor frame. The motor unit is supported on the motor frame via a support arm and an elastic support. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6455654 Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned conventional technology, the fixed point between the support arm and the motor unit is located above the motor unit, resulting in a large distance between the fixed point and the rotation center (rotor center) of the motor unit. This results in a large load (weight) on the support arm, necessitating a strong arm structure and fixation that can withstand such a large load. Furthermore, in electric vehicles equipped with motor units such as those of the conventional technology, noise and vibrations are generated by the motor, tires, and gears of intervening reducers, etc., and these noises and vibrations may be transmitted from the support frame through the vehicle body into the passenger compartment. Therefore, it is necessary to suppress the transmission of these noises and vibrations.

[0006] The present disclosure aims to solve the above-mentioned problems. [Means for solving the problem]

[0007] An aspect of the present disclosure is a motor support structure provided on a vehicle, comprising a motor frame, a motor unit arranged below the motor frame, and a pair of support arms extending downward from the motor frame and connected to both ends of the motor axial direction, which is the axial direction of the motor unit, to support the motor unit, wherein the upper ends of the pair of support arms are each supported by the motor frame via a pair of elastic supports, and the lower ends of the pair of support arms are fixed to at least the lower part of the motor unit. [Effects of the Invention]

[0008] According to the motor support structure of the present disclosure, the lower portions of the pair of support arms are fixed to the lower portion of the motor unit, thereby efficiently supporting the load of the motor unit, which generates high rotation and high torque. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a motor support structure according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a front view of the motor support structure. [Figure 3] FIG. 3 is a left side view of the motor support structure. [Figure 4] FIG. 4 is a right side view of the motor support structure. DETAILED DESCRIPTION OF THE INVENTION

[0010] As shown in FIG. 1, the motor support structure 10 according to this embodiment is a structure provided on a vehicle 100. The vehicle 100 is an electric vehicle. In the following description, "forward" means forward in the vehicle's longitudinal direction (X direction). "Rear" means rearward in the vehicle's longitudinal direction. The X1 direction is forward. The X2 direction is rearward. "Upward" means upward in the vertical direction (Z direction). "Downward" means downward in the vertical direction. The vehicle width direction (Y direction) is the left-right direction of the vehicle 100. Within the vehicle width direction, the Y1 direction is the right direction, and the Y2 direction is the left direction.

[0011] The motor support structure 10 is disposed in a storage compartment 102 located in the front 100Fr of the vehicle 100. The storage compartment 102 is a motor room. The motor support structure 10 is supported by side frames 104 (104L, 104R) disposed on both the left and right sides of the vehicle 100. The left and right side frames 104 are part of the body frame and are frames that extend in the fore-and-aft direction of the vehicle 100 on both the left and right sides of the vehicle 100.

[0012] The motor support structure 10 includes a motor unit 12, a power supply unit 14, a motor frame 16, a pair of mounting brackets 18 (18L, 18R), and a pair of support arms 20 (20L, 20R).

[0013] The motor unit 12 is a drive source for propelling the vehicle 100. The motor unit 12 is supported by the lower part of the motor frame 16. Specifically, both sides of the motor unit 12 in the vehicle width direction (Y direction) are fixed to the lower part of the motor frame 16 via a pair of support arms 20.

[0014] The motor unit 12 has an electric motor 22 and a reducer 24. Although not shown in detail, the electric motor 22 has a stator and a rotor. The rotor rotates by power supplied from a battery (not shown) via a power supply unit 14. In this embodiment, the rotation axis Ax of the rotor is parallel to the vehicle width direction (Y direction). The reducer 24 reduces the speed of rotation of the electric motor 22 and outputs the rotation to a drive shaft (not shown).

[0015] In another aspect, the motor unit 12 may be disposed so that the rotational axis Ax of the rotor intersects with the vehicle width direction. Therefore, the motor unit 12 may be disposed so that the rotational axis Ax of the rotor is parallel to the longitudinal direction of the vehicle, for example. In the following description, the axial direction of the motor unit 12 is referred to as the "motor axial direction." The axial direction of the motor unit 12 is the direction along the rotational axis Ax of the rotor.

[0016] The power supply unit 14 is an electrical device for supplying power to the electric motor 22. The power supply unit 14 is supported by the upper part of the motor frame 16. That is, the lower part of the power supply unit 14 is fixed to the upper part (top surface) of the motor frame 16.

[0017] Although detailed description will be omitted, the power supply unit 14 has a converter 26, a junction box 28, and an inverter 30. The converter 26, junction box 28, and inverter 30 are housed in a case 15 and configured as a single unit. Here, the power supply unit 14 includes electrical safety protection components required for electrification. The converter 26 is a DC / DC converter that converts voltage. The junction box 28 provides wiring between the converter 26 and the inverter 30. The inverter 30 supplies AC power to the electric motor 22.

[0018] The motor frame 16 is supported on the left and right side frames 104 via a pair of mounting brackets 18. The motor frame 16 has a frame main body 32 and at least one protruding frame .

[0019] The frame body 32 extends in the vehicle width direction. The thickness, which is the dimension of the frame body 32 in the up-down direction, is smaller than the dimension of the frame body 32 in the vehicle width direction and is also smaller than the dimension of the frame body 32 in the vehicle front-rear direction. In other words, the frame body 32 has a flat shape with a thickness that is relatively small compared to the dimensions in the left-right direction and the front-rear direction. The frame body 32 is made of a metal material. The frame body 32 is made of, for example, steel. The frame body 32 may have a hollow structure or a solid structure.

[0020] The frame main body 32 has a pair of frame end portions 36 (36L, 36R) and a frame central portion 38. The pair of frame end portions 36 are located on both sides of the frame main body 32 in the vehicle width direction. The frame central portion 38 is a portion of the frame main body 32 that connects one frame end portion 36L and the other frame end portion 36R.

[0021] In this embodiment, the motor frame 16 has a plurality of (two in the illustrated example) protruding frames 34. The plurality of protruding frames 34 are fixed to the upper surface of the frame main body 32. The plurality of protruding frames 34 are arranged at intervals from one another in the vehicle width direction. The plurality of protruding frames 34 extend parallel to one another in the vehicle front-rear direction. The power supply unit 14 is fixed to the plurality of protruding frames 34. Note that only one protruding frame 34 may be provided, or three or more protruding frames 34 may be provided.

[0022] The pair of mount brackets 18 connect the frame ends 36 of the frame main body 32 to the left and right side frames 104 of the vehicle 100. Each mount bracket 18 is made of a material that is weaker than the frame main body 32. The mount brackets 18 are made of a metal material. For example, the mount brackets 18 are made of an aluminum alloy.

[0023] The left mounting bracket 18L is fixed to the left frame end 36L of the frame main body 32 with a bolt 46. The left mounting bracket 18L is fixed to the left side frame 104L with a bolt 46. The right mounting bracket 18R is fixed to the right frame end 36R of the frame main body 32 with a bolt 46. The right mounting bracket 18R is fixed to the right side frame 104R with a bolt 46.

[0024] In the following description, when distinguishing between the pair of support arms 20, the left support arm 20 will be referred to as "support arm 20L" and the right support arm 20 will be referred to as "support arm 20R." The pair of support arms 20 support the motor unit 12. The pair of support arms 20 are made of a metal material (e.g., steel).

[0025] In this embodiment, the pair of support arms 20 have different shapes when viewed in the motor axial direction. In another aspect, the pair of support arms 20 may have the same shape when viewed in the motor axial direction. As shown in FIG. 2 , in this embodiment, the pair of support arms 20 have an asymmetric shape in the vehicle width direction. In another aspect, the pair of support arms 20 may have a symmetric shape in the vehicle width direction. The pair of support arms 20 extend downward from the motor frame 16. The pair of support arms 20 are connected to both axial ends of the motor unit 12.

[0026] 1, the upper ends of the pair of support arms 20 are supported by the motor frame 16 via a pair of elastic supports 50. Therefore, the pair of support arms 20 are suspended from the motor frame 16 via the pair of elastic supports 50.

[0027] The pair of elastic supports 50 are structural parts for floatingly supporting the motor unit 12. Therefore, the pair of support arms 20 are displaceable within a predetermined movable range relative to the motor frame 16. Each elastic support 50 is a bush made of an elastic material such as rubber or elastomer.

[0028] The pair of elastic supports 50 are held by the frame main body 32. Specifically, the frame main body 32 has a pair of holders 52 that hold the pair of elastic supports 50. The pair of holders 52 protrude downward from both longitudinal end portions (frame end portions 36) of the frame main body 32. As shown in FIGS. 3 and 4 , each holder 52 has a holding hole 53 that holds the elastic supports 50. Each holding hole 53 is a hole that penetrates in the vehicle width direction. The pair of elastic supports 50 are inserted into the pair of holding holes 53, respectively.

[0029] Each elastic support 50 has a support hole 500, a first hole 501, and a second hole 502. The support hole 500, the first hole 501, and the second hole 502 penetrate the elastic support 50 in the vehicle width direction. The support hole 500 and the first hole 501 are formed in the upper part of the elastic support 50. An insertion protrusion 58 provided on the upper end of the support arm 20 is inserted into the support hole 500. The insertion protrusion 58 is supported by the support hole 500. The first hole 501 is formed so as to surround the front, upper, and rear of the support hole 500. The second hole 502 is formed in the lower part of the elastic support 50. The second hole 502 is formed below the support hole 500.

[0030] The elastic support 50 has a pair of support pillars 504 formed between the first hole 501 and the second hole 502. The pair of support pillars 504 are located at the front and rear of the elastic support 50. The pair of support pillars 504 elastically deform to absorb shocks and vibrations from the motor unit 12. The elastic support 50 further has a surrounding wall 506 that surrounds the support hole 500 between the support hole 500 and the first hole 501.

[0031] A pair of stoppers 508 are formed on the front and rear of the surrounding wall 506, protruding forward and rearward toward the first hole 501. The pair of stoppers 508 face a pair of opposing portions 510 of the elastic support body 50, respectively. When a strong impact or vibration occurs, the front or rear stopper 508 comes into contact with the front or rear opposing portion 510, thereby restricting deformation of the support portion 504.

[0032] Here, the upper part 12UP and lower part 12LW of the motor unit 12 are defined as follows: The upper part 12UP of the motor unit 12 is the part above the center of the motor unit 12 in the vertical direction. The lower part 12LW of the motor unit 12 is the part below the center of the motor unit 12 in the vertical direction. In other words, when an imaginary line L is drawn to divide the motor unit 12 into two equal parts in the vertical direction, the area above the imaginary line L is the "upper part 12UP of the motor unit 12," and the area below the imaginary line L is the "lower part 12LW of the motor unit 12."

[0033] As shown in FIG. 2, each support arm 20 has an arm main body 56 and the above-described insertion protrusion 58. The insertion protrusion 58 protrudes from the upper end of the arm main body 56 in the motor axis direction (Y direction). In each support arm 20, the insertion protrusion 58 protrudes in the same direction (leftward) from the upper end of the arm main body 56. The protrusion directions of the insertion protrusions 58 in a pair of support arms 20 from the arm main body 56 may be opposite to each other. For example, in the left support arm 20L, the insertion protrusion 58 may protrude leftward (Y2 direction) from the upper end of the arm main body 56, and in the right support arm 20R, the insertion protrusion 58 may protrude rightward (Y1 direction) from the upper end of the arm main body 56. Alternatively, in the left support arm 20L, the insertion protrusion 58 may protrude to the right (Y1 direction) from the upper end of the arm main body 56, and in the right support arm 20R, the insertion protrusion 58 may protrude to the left (Y2 direction) from the upper end of the arm main body 56.

[0034] As shown in Figures 3 and 4, the lower part of each support arm 20 is fixed (fastened) to at least the lower part 12LW of the motor unit 12. Each support arm 20 (specifically, each arm body 56) is fixed to the motor unit 12 via a plurality of fixing points 60. Each fixing point 60 is a fastening member 60A. In this embodiment, each support arm 20 is fixed to the motor unit 12 via four fixing points 60. It is preferable that three or more fixing points 60 are provided for each support arm 20. Five or more fixing points 60 may be provided for each support arm 20. Each fastening member 60A is, for example, a bolt.

[0035] At least one fixed point 60 of each of the pair of support arms 20 for the motor unit 12 is located below the center of gravity G of the motor unit 12. In this embodiment, multiple fixed points 60 are located below the center of gravity G of the motor unit 12. As in this embodiment, at least one fixed point 60 may be located above the center of gravity G of the motor unit 12. In this embodiment, the number of fixed points 60 located below the center of gravity G of the motor unit 12 is greater than the number of fixed points 60 located above the center of gravity G of the motor unit 12. In another aspect, all of the fixed points 60 may be located below the center of gravity G of the motor unit 12. The rotation axis Ax of the rotor is located below the center of gravity G of the motor unit 12.

[0036] In each support arm 20, the lower arm portion 202 is wider in the horizontal direction (vehicle front-rear direction) perpendicular to the motor axial direction than the upper arm portion 201. Specifically, each support arm 20 has a shape that gradually widens downward. The upper arm portion 201 is a portion above the center of the support arm 20 in the up-down direction. The lower arm portion 202 is a portion below the center of the support arm 20 in the up-down direction.

[0037] Each support arm 20 is a frame with a truss structure. Therefore, each support arm 20 has a plurality of columnar frame elements 21. A plurality of openings 210 are formed between the plurality of frame elements 21. One frame element 21a in each support arm 20 extends so as to connect the front and rear of the support arm 20 (arm main body 56).

[0038] When viewed from the motor axis direction, each support arm 20 is positioned so that the center of gravity G of the motor unit 12 is located inside the outline of the support arm 20. When viewed from the motor axis direction, the multiple fixing points 60 are positioned so as to surround the center of gravity G of the motor unit 12. At least one fixing point 60 on each support arm 20 is located below the center of gravity G. As in this embodiment, it is preferable that the multiple fixing points 60 are located below the center of gravity G of the motor unit 12. At least one fixing point 60 on each support arm 20 is located forward of the center of gravity G. At least one fixing point 60 on each support arm 20 is located rearward of the center of gravity G.

[0039] The motor support structure 10 further includes a connecting portion 62 that connects the motor unit 12 to a subframe 106 of the vehicle body. The connecting portion 62 is a structural portion that mainly restricts displacement of the motor unit 12 in the fore-and-aft direction of the vehicle.

[0040] The connecting portion 62 has a bracket 64, a connecting rod 66, a bushing 68, and a fixed shaft 70. The bracket 64 is fixed to the motor unit 12. In this embodiment, the bracket 64 is fixed to the lower rear side of the speed reducer 24. The connecting rod 66 is connected to the bracket 64 so as to be rotatable about an axis along the vehicle width direction. The bushing 68 is held at the rear end of the connecting rod 66. The bushing 68 is a vibration absorbing member made of an elastic body such as rubber. The fixed shaft 70 is inserted into the bushing 68. The fixed shaft 70 is fixed to the subframe 106.

[0041] This embodiment has the following advantages.

[0042] In the motor support structure 10, the upper ends of a pair of support arms 20 are supported by the motor frame 16 via a pair of elastic supports 50. The lower portions of the pair of support arms 20 are fixed to at least the lower portion of the motor unit 12. With this configuration, because the lower portions of the pair of support arms 20 are fixed to the lower portion 12LW of the motor unit 12, it is possible to efficiently support the load of the motor unit 12, which generates high rotation and high torque.

[0043] At least one fixing point 60 (fastening member 60A) of each of the pair of support arms 20 to the motor unit 12 is located below the center of gravity G of the motor unit 12. With this configuration, the load of the motor unit 12 can be supported more efficiently.

[0044] In each of the pair of support arms 20, the lower arm portion 202 is wider in the horizontal direction perpendicular to the motor axis direction than the upper arm portion 201. Each of the pair of support arms 20 is fixed to the motor unit 12 at multiple fixing points 60. With this configuration, the wider lower arm portion 202 makes it easy to provide multiple fixing points 60 on the lower arm portion 202. Furthermore, since the support arm 20 has multiple fixing points 60 for the motor unit 12, the support load (weight) of the motor unit 12 can be distributed across the multiple fixing points 60. This reduces the fixing strength required for each fixing point 60. Furthermore, since the lower arm portion 202 is wide and has a fan shape, so to speak, the fastening point to the lower portion of the motor unit 12 can be set relatively freely. This allows for setting an appropriate fastening point to withstand vibrations from the motor unit 12, and suppresses transmission of vibrations to the vehicle body.

[0045] When viewed from the motor axial direction, the pair of support arms 20 are arranged so that the center of gravity G of the motor unit 12 is located inside the outline of each of the pair of support arms 20. With this configuration, the support load (weight) of the motor unit 12 can be efficiently distributed to the multiple fixing points 60, so the fixing strength required for each fixing point 60 can be further effectively reduced.

[0046] When viewed from the motor axial direction, the multiple fixing points 60 are arranged to surround the center of gravity G of the motor unit 12. With this configuration, the support load (weight) of the motor unit 12 can be efficiently distributed to the multiple fixing points 60, so the fixing strength required for each fixing point 60 can be more effectively reduced.

[0047] Each of the pair of support arms 20 is a frame having a truss structure. This configuration makes it easy to increase the moment of inertia of the support arm 20. Therefore, by ensuring sufficient rigidity of the support arm 20, the load of the motor unit 12 can be effectively supported. Specifically, the support arm 20 generates and transmits strong vibrations (including noise) accompanied by torsional components due to the motor, tires, and gears of an intervening reducer, etc. However, the frame cross-sectional structure and truss structure of the support arm 20 can be designed to have sufficient rigidity, thereby suppressing the transmission of vibrations generated by the structure related to this support arm 20 to the vehicle body. Furthermore, because the support arm 20 has a truss structure, it is structured to be divided into multiple arms, such as front and rear arms. For example, the rigidity of the front and rear arm members leading to the elastic support 50 can be designed based on the vibration characteristics of the motor unit 12, etc., and the transmission of generated vibrations can be controlled and appropriately suppressed.

[0048] The following additional notes are further disclosed regarding the above embodiment.

[0049] (Appendix 1) The motor support structure (10) of the present disclosure is a motor support structure provided on a vehicle (100), and comprises a motor frame (16), a motor unit (12) arranged below the motor frame, and a pair of support arms (20) extending downward from the motor frame and connected to both ends of the motor axial direction, which is the axial direction of the motor unit, to support the motor unit, with the upper ends of the pair of support arms each supported by the motor frame via a pair of elastic supports (50), and the lower ends of the pair of support arms fixed to at least the lower part (12LW) of the motor unit.

[0050] With this configuration, the lower portions of the pair of support arms are fixed to the lower portion of the motor unit, so that the load of the motor unit, which generates high rotation and torque, can be efficiently supported.

[0051] (Supplementary Note 2) In the motor support structure described in Supplementary Note 1, at least one fixing point (60) of each of the pair of support arms to the motor unit may be located below the center of gravity (G) of the motor unit.

[0052] With this configuration, the load of the motor unit can be supported more efficiently.

[0053] (Appendix 3) In the motor support structure described in Appendix 1 or 2, in each of the pair of support arms, the lower arm portion (202) is wider in a horizontal direction perpendicular to the motor axis direction than the upper arm portion (201), and each of the pair of support arms may be fixed to the motor unit at multiple fixing points.

[0054] With this configuration, the support arm has multiple fixing points to the motor unit, so the load (weight) of the motor unit can be distributed among the multiple fixing points, reducing the fixing strength required for each fixing point.

[0055] (Appendix 4) In the motor support structure described in any one of Appendices 1 to 3, the pair of support arms may be arranged so that, when viewed from the motor axial direction, the center of gravity of the motor unit is located inside the outline of each of the pair of support arms.

[0056] With this configuration, the supporting load (weight) of the motor unit can be efficiently distributed to a plurality of fixing points, so that the fixing strength required for each fixing point can be further effectively reduced.

[0057] (Supplementary Note 5) In the motor support structure described in Supplementary Note 4, the plurality of fixing points may be arranged to surround the center of gravity of the motor unit when viewed in the motor axial direction.

[0058] With this configuration, the supporting load (weight) of the motor unit can be efficiently distributed to a plurality of fixing points, so that the fixing strength required for each fixing point can be further effectively reduced.

[0059] (Supplementary Note 6) In the motor support structure according to any one of Supplementary Notes 1 to 5, each of the pair of support arms may be a frame having a truss structure.

[0060] This configuration makes it easy to increase the moment of inertia of the support arm, thereby ensuring sufficient rigidity of the support arm and allowing it to effectively bear the load of the motor unit.

[0061] Although the present disclosure has been described in detail, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments. [Explanation of symbols]

[0062] 10...Motor support structure 12...Motor unit 16...Motor frame 20, 20L, 20R...Support arms 50...Elastic support body 56...Arm body 58...insertion protrusion 60...fixing point 60A...Fastening member

Claims

1. A motor support structure provided in a vehicle, A motor frame; a motor unit disposed below the motor frame; a pair of support arms extending downward from the motor frame, connected to both ends in a motor axial direction that is the axial direction of the motor unit, and supporting the motor unit; upper ends of the pair of support arms are supported by the motor frame via a pair of elastic supports, A motor support structure, wherein lower portions of the pair of support arms are fixed to at least a lower portion of the motor unit.

2. 2. The motor support structure according to claim 1, A motor support structure in which at least one fixed point of each of the pair of support arms relative to the motor unit is located below the center of gravity of the motor unit.

3. 2. The motor support structure according to claim 1, In each of the pair of support arms, the arm lower portion is wider in a horizontal direction perpendicular to the motor axial direction than the arm upper portion, A motor support structure, wherein each of the pair of support arms is fixed to the motor unit at a plurality of fixing points.

4. 4. The motor support structure according to claim 3, A motor support structure, wherein the pair of support arms are arranged so that the center of gravity of the motor unit is located inside the outline of each of the pair of support arms when viewed from the motor axial direction.

5. 5. The motor support structure according to claim 4, A motor support structure, wherein the plurality of fixing points are arranged to surround the center of gravity of the motor unit when viewed from the motor axial direction.

6. The motor support structure according to any one of claims 1 to 5, A motor support structure, wherein each of the pair of support arms is a frame having a truss structure.

Images