Vibration isolation device with bracket

Abstract

This invention provides a novel bracket-equipped vibration isolation device for use in electric vehicles that reduces or avoids the risk of damage to wire harnesses in the event of a collision between the body-side bracket and other components during an automobile accident. [Solution] A vibration damping device 10 with a bracket for vibration-damping support of an electric motor 68 relative to a vehicle body 66 in an electric vehicle, comprising a body-side bracket 14 fixed to the vehicle body 66, the body-side bracket 14 being provided with fixing parts 42, 44 fixed to the vehicle body 66 at multiple locations in the front-rear direction of the vehicle, the body-side bracket 14 having a front-end projection 46 that is biased toward the rear side of the vehicle and partially protrudes toward other members 70 on the vehicle body 66 side, the projection height of the front-end projection 46 is set so that even when the front-end projection 46 is in contact with the other members 70, space for wiring a wire harness 72 is secured between it and the other members 70.

Description

Technical Field

[0001] The present invention relates to a vibration isolation device with a bracket that vibration-isolates a drive motor to a vehicle body in an electric vehicle.

Background Art

[0002] In an electric vehicle, a drive motor is vibration-isolated and supported to a vehicle body via a vibration isolation device with a bracket. The vibration isolation device with a bracket has a structure in which a body-side bracket is attached to a cylindrical mount body, as disclosed in, for example, Japanese Unexamined Patent Application Publication No. 2021-089052 (Patent Document 1). Note that an electric vehicle refers to a self-propelled vehicle equipped with an electric motor as a driving means, and includes, in addition to a BEV (battery electric vehicle), for example, a PHEV (plug-in hybrid vehicle), a HEV (hybrid vehicle), a FCEV (fuel cell electric vehicle), and the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] <J By the way, a power cable (wire harness) is connected to the drive motor to supply power. In an electric vehicle, many peripheral devices such as a storage battery, a generator, and a motor control device are equipped, and the wire harness must be wired through a limited and narrow space.

[0005] Here, since the vibration isolation device with a bracket is generally fixed to the vehicle body side via a body-side bracket having a shape with a fixed leg that partially extends toward the vehicle body side, it may be easy to secure space around it, and it is easy to wire the wire harness through the peripheral space of the vibration isolation device with a bracket.

[0006] However, the inventors' investigations revealed that if a vehicle is severely deformed in an accident, the wire harness routed in the space surrounding the bracket-equipped vibration damper may cause new problems. Specifically, the body-side bracket in the bracket-equipped vibration damper is a highly rigid member with large load-bearing capacity. When the body-side bracket strikes another member (for example, the dash cross member that partitions the passenger compartment) in a car accident, a very large crushing force acts on the wire harness sandwiched between the two members. In particular, the wire harness supplying power to the drive motor carries a large amount of power (voltage and current), and a short circuit due to crushing could limit accident rescue operations.

[0007] Furthermore, while we considered adding protective covers to the wire harnesses as a countermeasure to these problems, the protective covers would need to be larger and more rigid to withstand the large loads applied during a car accident, making it difficult even to route the wire harnesses in the narrow wiring space of a vehicle by bending them. In particular, the body-side brackets are often fixed using fastening bolts, and in the event of a car accident, the heads of the fastening bolts protruding from the body-side brackets are pressed against the wire harnesses, making it easy for even greater crushing forces to be locally applied to the wire harnesses. Therefore, protecting the wire harnesses with protective covers proved to be extremely difficult.

[0008] The problem to be solved by the present invention is to provide a novel bracket-equipped vibration damping device for use in electric vehicles that can reduce or avoid the risk of damage to the wire harness routed around the vibration damping device even when the body-side bracket strikes another component of the vehicle body in the event of a car accident. [Means for solving the problem]

[0009] The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is illustrative and can be combined with others as appropriate. Furthermore, the multiple components described in each embodiment can be recognized and adopted as independently as possible, and can be combined with any component described in another embodiment as appropriate. Thus, the present invention is not limited to the embodiments described below, and various other embodiments can be realized.

[0010] The first embodiment is a vibration damping device with a bracket for vibration-damping support of an electric motor relative to the vehicle body in an electric vehicle, comprising a body-side bracket fixed to the vehicle body, the body-side bracket having fixing portions fixed to the vehicle body at multiple locations in the front-rear direction of the electric vehicle, the body-side bracket having a front-end projection that is biased toward the rear side of the electric vehicle and partially protrudes toward other members of the vehicle body, the projection height of the front-end projection is set such that even when the front-end projection is in contact with the other member of the vehicle body, space for wiring a wire harness is secured between the other member of the vehicle body and the front-end projection.

[0011] According to the bracket-equipped vibration isolation device constructed in accordance with this embodiment, a forward-facing projection, which partially protrudes from the body-side bracket toward other members of the vehicle body, can strike the other members of the vehicle body before the vehicle body deforms due to a vehicle collision, thereby limiting the amount of movement of the body-side bracket toward those other members. As a result, space for wiring the wire harness can be secured between the body-side bracket and the other members of the vehicle body, thus protecting the wire harness even in the event of an electric vehicle accident without requiring excessive protective covers for the wire harness.

[0012] In the first embodiment, "uneven distribution" refers to a configuration in which the front-contact projection is located on the rear side, where the body-side bracket is more likely to strike other components (such as the dash cross member) during a vehicle accident. For example, even if the front-contact projection is provided to extend along the entire length of the vehicle in the longitudinal direction, the height of the projection toward other components is greater on the rear side than on the front side, so that it is closer to and facing those other components. Furthermore, since the body-side bracket is fixed to the vehicle body at multiple points in the longitudinal direction of the vehicle, it can accurately and stably follow the deformation of the vehicle body. As a result, the body-side bracket's impact with other components during a vehicle accident, i.e., the securing of space for wiring the wire harness by the front-contact projection striking other components, can be performed more stably.

[0013] The second embodiment is a vibration damping device with a bracket as described in the first embodiment, wherein the body-side bracket is mounted on a cylindrical vibration damping device having a structure in which an inner shaft member and an outer cylindrical member are elastically connected by a main rubber elastic body, and the cylindrical vibration damping device is mounted on the vehicle body with the central axis of the inner shaft member facing in the left-right direction of the vehicle.

[0014] As with the bracket-type vibration damper structured according to this embodiment, a cylindrical vibration damper can also be used as the vibration damper. Furthermore, by having the central axis of the inner shaft member oriented in the left-right direction of the vehicle, it becomes easier to miniaturize the bracket-type vibration damper in the left-right direction of the vehicle while also facilitating the provision of a front-end projection that is predominantly located on the rear side of the vehicle.

[0015] The third embodiment is a vibration isolation device with a bracket as described in the second embodiment, wherein the motor-side bracket is fixed to the inner shaft member with fastening bolts, while the body-side bracket is fixed to the outer cylindrical member in an externally fitted state.

[0016] According to the bracket-equipped vibration isolation device with a structure conforming to this embodiment, the longitudinal direction of the electric vehicle is the radial direction of the outer cylindrical member. Therefore, it is easier to obtain a large longitudinal dimension for the fixing portion of the outer cylindrical member in the vehicle longitudinal direction while keeping the lateral dimension of the press-fit portion of the outer cylindrical member in the body-side bracket small. Consequently, it is easier to provide a front-end projection that is biased towards the rear of the electric vehicle, and it is easier to secure space for wiring a wire harness in front of the front-end projection in the event of a vehicle accident.

[0017] The fourth embodiment is a vibration isolation device with a bracket as described in the third embodiment, wherein the front abutment projection is provided so as to partially protrude from the outer circumferential surface of the body-side bracket.

[0018] According to the bracket-equipped vibration damping device with a structure conforming to this embodiment, by providing a front-facing projection on the outer circumferential surface of the body-side bracket, which is fixed to the outer cylindrical member in an externally fitted state, it is possible to miniaturize the bracket-equipped vibration damping device in the left-right direction of the vehicle while securing space for wiring the wire harness on the outer circumferential side of the body-side bracket.

[0019] The fifth embodiment is a vibration damping device with a bracket as described in the fourth embodiment, wherein the lower part of the body-side bracket has multiple fixing portions to the vehicle body at different locations in the vehicle's longitudinal direction, while the upper part has the front-end projections that are predominantly located and protrude toward the rear of the vehicle.

[0020] According to the bracket-equipped vibration isolation device constructed in accordance with this embodiment, for example, when the front abutment projection strikes another member in the event of a vehicle accident, the contact reaction force acting on the body-side bracket due to the impact acts toward the fixing part to the vehicle body, which is located on the opposite side of the front abutment projection of the body-side bracket. Therefore, problems such as the body-side bracket collapsing due to the action of the contact reaction force are less likely to occur. In particular, since the fixing parts are provided at multiple different locations in the front-rear direction of the vehicle, the above-mentioned contact reaction force can be received more stably.

[0021] The sixth aspect is the anti-vibration device with a bracket described in any one of the second to fifth aspects, wherein a fail-safe mechanism is provided to prevent relative separation between the inner shaft member and the outer cylinder member even if the main body rubber elastic body breaks.

[0022] According to the anti-vibration device with a bracket having the structure according to this aspect, even if the main body rubber elastic body breaks due to a vehicle accident or the like, the separation between the inner shaft member and the outer cylinder member is prevented by the fail-safe mechanism, thereby preventing the electric motor from falling off onto the road surface or the like.

[0023] The seventh aspect is the anti-vibration device with a bracket described in the sixth aspect, wherein the fail-safe mechanism includes a pair of fixed arm portions fixed to both axial ends of the inner shaft member inserted and disposed in the mounting hole of the body side bracket by the motor side bracket, and is configured by preventing the inner shaft member from detaching from the mounting hole of the body side bracket.

[0024] According to the anti-vibration device with a bracket having the structure according to this aspect, since a pair of fixed arm portions are fixed to both axial ends of the inner shaft member, the inner shaft member to which the motor side bracket is attached cannot axially come out from the mounting hole of the body side bracket. Therefore, it is possible to prevent the inner shaft member from separating from the outer cylinder member fixed in the inserted state in the mounting hole of the body side bracket and the electric motor from falling off.

[0025] Since the fail-safe mechanism of this aspect is configured by fixing the motor side bracket to both axial ends of the inner shaft member, there is no need to provide separate parts only for constituting the fail-safe mechanism.

[0026] The eighth aspect is the anti-vibration device with a bracket described in any one of the third to seventh aspects, wherein the motor side bracket extends from the inner shaft member toward the front side of the electric vehicle, and the abutting protrusion of the body side bracket is unevenly distributed on the rear side of the electric vehicle.

[0027] According to the vibration isolator with a bracket having a structure according to this aspect, when the impact projection part hits another member due to a vehicle accident or the like, the motor side bracket extending from the inner shaft member toward the vehicle front side is less likely to interfere with the wire harness, and damage to the wire harness due to contact with the motor side bracket is more easily avoided.

[0028] A ninth aspect is the vibration isolator with a bracket according to any one of the first to eighth aspects, wherein the impact projection part expands from the protruding tip end part toward the base end side.

[0029] According to the vibration isolator with a bracket having a structure according to this aspect, since the load-bearing performance in the protruding direction of the impact projection part is improved, the strength of the impact projection part against the impact of other members is ensured, and a wiring space for the wire harness is more reliably secured.

[0030] Further, since the impact projection part has a tapered shape, the arrangement space of the tip part of the impact projection part is made relatively small, and interference with other members located around the tip side of the impact projection part is avoided.

[0031] A tenth aspect is the vibration isolator with a bracket according to any one of the first to ninth aspects, wherein the impact projection part has a smooth surface shape without corners on the entire protruding tip end surface.

[0032] According to the vibration isolator with a bracket having a structure according to this aspect, when the impact projection part hits another member, it is possible to prevent the load from concentrating on the contact portion of the impact projection part with the corner, and the durability of other members and the impact projection part is improved by the dispersion of the load.

[0033] Further, even if the impact projection part is slightly pressed against the wire harness when the impact projection part contacts another member due to a vehicle accident or the like, since the surface of the impact projection part has a smooth shape without corners, problems such as biting into the wire harness are avoided.

[0034] The eleventh embodiment is a vibration isolation device with a bracket as described in any one of the first to tenth embodiments, wherein the front abutment projection does not protrude laterally from the body-side bracket.

[0035] According to the bracket-equipped vibration isolation device with a structure conforming to this embodiment, the substantial increase in the size of the body-side bracket due to the front abutment projection is avoided. Furthermore, since the front abutment projection does not protrude laterally from the body-side bracket, interference between the front abutment projection and members located laterally to the body-side bracket is avoided.

[0036] The twelfth embodiment is a vibration isolation device with a bracket as described in any one of the first to eleventh embodiments, wherein the front projection has a flat surface at its protruding tip.

[0037] According to the bracket-equipped vibration isolation device with a structure conforming to this embodiment, the flat surface provided on the protruding tip surface of the abutment projection makes surface contact with other members, thereby distributing the stress during contact.

[0038] The thirteenth aspect is a vibration isolation device with a bracket as described in the twelfth aspect, wherein the front side of the flat surface of the front abutment projection is provided with a forward inclined surface having a smaller inclination angle than the rear side.

[0039] According to the bracket-equipped vibration damping device with a structure conforming to this embodiment, the flat surface can be easily positioned towards the rear, making it easier to skew the front abutment projection towards the rear of the vehicle. Furthermore, by providing a forward-sloping surface, taking into consideration the manner in which the front abutment projection contacts other members and the manner in which other members deform due to contact with the front abutment projection, it is possible to distribute the stress when the front abutment projection contacts other members and reduce the amount of deformation of other members due to contact. [Effects of the Invention]

[0040] According to the present invention, in a vibration damping device with a bracket used in an electric vehicle, even if the bracket strikes another component on the vehicle body side in the event of a car accident, the risk of damage to the wire harness routed around the vibration damping device can be reduced or avoided. [Brief explanation of the drawing]

[0041] [Figure 1] A perspective view showing a vibration isolation device with a bracket as the first embodiment of the present invention, with the motor-side bracket attached. [Figure 2] Side view of the bracket-equipped vibration isolation device shown in Figure 1. [Figure 3] Rear view of the bracket-equipped vibration isolation device shown in Figure 1. [Figure 4] A side view of the vibration isolation device with bracket shown in Figure 1, with the motor-side bracket removed. [Figure 5] Figure 1 shows a side view illustrating the contact between the front abutment projection and the dash cross member when the vibration damping device with bracket is mounted on a vehicle. [Figure 6] A side view showing the contact state between the body-side bracket and the dash crossmember in a vehicle-mounted conventional bracket-type vibration damping device. [Modes for carrying out the invention]

[0042] Embodiments of the present invention will be described below with reference to the drawings.

[0043] Figures 1 to 3 show a bracket-equipped vibration damping device 10 as a first embodiment of the present invention, with the motor-side bracket 54 (described later) attached. The bracket-equipped vibration damping device 10 is used to vibration-dampe an electric motor 68 (described later) against a vehicle body 66 (also described later), and has a structure in which a body-side bracket 14 is attached to a cylindrical vibration damping device 12. In the following description, as a general rule, the vertical direction refers to the vertical direction in Figure 2, the front-rear direction refers to the left-right direction in Figure 2, and the left-right direction refers to the left-right direction in Figure 3.

[0044] As shown in Figure 4, the cylindrical vibration isolation device 12 has a structure in which the inner shaft member 16 and the outer cylindrical member 18 are connected by the main rubber elastic body 20.

[0045] The inner shaft member 16 is a rigid member made of metal or the like, and integrally comprises a roughly octagonal prism-shaped fixing portion 22 and a pair of bracket fastening portions 24, 24 that protrude from the fixing portion 22 on both sides in the axial direction. The bracket fastening portions 24 have a smaller diameter than the fixing portion 22 and their upper surfaces form fastening surfaces 26 that spread out substantially perpendicular to the vertical direction. The bracket fastening portions 24 have screw holes (not shown) that open into the fastening surfaces 26, and fastening bolts 64, which will be described later, can be screwed into these screw holes. The bracket fastening portions 24 are positioned offset downward from the fixing portion 22, but their lower parts are narrower in the front-rear direction toward the bottom, so that they do not protrude outward from the fixing portion 22.

[0046] The outer cylindrical member 18 is a hard member made of metal or the like, and has a thin-walled, large-diameter, substantially cylindrical shape. The inner diameter of the outer cylindrical member 18 is larger than the maximum outer diameter of the fixing portion 22 of the inner shaft member 16, and is sized to be able to be extrapolated onto the inner shaft member 16 with a gap.

[0047] The fixing portion 22 of the inner shaft member 16 is inserted into the inner circumference of the outer cylindrical member 18, and the main rubber elastic body 20 is provided radially between the fixing portion 22 of the inner shaft member 16 and the outer cylindrical member 18. The main rubber elastic body 20 is generally thick-walled and has a substantially cylindrical shape. Its inner circumferential surface is vulcanized and bonded to the fixing portion 22 of the inner shaft member 16, and its outer circumferential surface is vulcanized and bonded to the outer cylindrical member 18. The main rubber elastic body 20 has a first cut hole 28 formed through the upper side relative to the inner shaft member 16, and a second cut hole 30 formed through the lower side relative to the inner shaft member 16. The first cut hole 28 penetrates the main rubber elastic body 20 axially between the upper part of the fixing portion 22 of the inner shaft member 16 and the outer cylindrical member 18 and extends circumferentially. The second hole 30 extends circumferentially, penetrating the main rubber elastic body 20 axially between the lower part of the fixing portion 22 on the inner shaft member 16 and the outer cylindrical member 18. The main rubber elastic body 20 is provided with a pair of rubber arms 32, 32 that connect the inner shaft member 16 and the outer cylindrical member 18 to each other in the circumferential direction between the first hole 28 and the second hole 30. The pair of rubber arms 32, 32 extend downward on both sides in the front-rear direction from the inner shaft member 16 toward the outer cylindrical member 18, with the inner circumferential end being vulcanized and bonded to the inner shaft member 16, and the outer circumferential end being vulcanized and bonded to the outer cylindrical member 18.

[0048] A first stopper rubber 34 is provided in the central part of the front-to-back direction of the first recess 28, protruding downward from the outer cylindrical member 18 towards the inner shaft member 16. A second stopper rubber 36 is provided in the central part of the front-to-back direction of the second recess 30, protruding upward from the outer cylindrical member 18 towards the inner shaft member 16. These first and second stopper rubbers 34 and 36 limit the relative displacement of the inner shaft member 16 and the outer cylindrical member 18 in the vertical direction, preventing damage to the main rubber elastic body 20 due to excessive deformation when vibration is input in the vertical direction.

[0049] A body-side bracket 14 is attached to the cylindrical vibration damping device 12. The body-side bracket 14 is a highly rigid member made of metal or the like, and as shown in Figures 1 to 4, it is in the shape of a thick plate and has a circular mounting hole 38 that penetrates in the left-right direction, which is the direction of the plate thickness. As a result, the upper part of the body-side bracket 14 in which the mounting hole 38 is formed is as a cylindrical mounting cylinder portion 40 as a whole. The lower part of the body-side bracket 14 is composed of a first mounting leg portion 42 that extends downward from the front of the mounting cylinder portion 40 as a fixing part, and a second mounting leg portion 44 that extends downward from the rear of the mounting cylinder portion 40 as a fixing part. Therefore, the body-side bracket 14 of this embodiment has fixing parts that are fixed to the vehicle body 66, which will be described later, at two locations in the front-rear direction. The first and second mounting legs 42 and 44 are, for example, provided with screw holes (not shown) that open on their lower surfaces, and can be fixed to the vehicle body 66, which will be described later. Furthermore, the mounting structure for the first and second mounting legs 42 and 44 to the vehicle body 66 is not limited to screw holes, but may also be a hook structure that is fixed by engagement with the vehicle body 66, for example.

[0050] The body-side bracket 14 is provided with a front stop projection 46. The front stop projection 46 is integrally formed with the mounting cylinder portion 40 of the body-side bracket 14 and is provided as a partial projection on the outer circumferential surface of the mounting cylinder portion 40. In this embodiment, the front stop projection 46 protrudes upward from the upper surface of the mounting cylinder portion 40 and constitutes the upper part of the body-side bracket 14. The front stop projection 46 extends in the left-right direction with a substantially constant cross-section. The left-right width dimension of the front stop projection 46 is substantially the same as the left-right width dimension of the mounting cylinder portion 40, and it does not protrude laterally relative to the mounting cylinder portion 40. In Figures 1 to 4 and Figure 5 described later, the boundary between the mounting cylinder portion 40 and the front stop projection 46 of the body-side bracket 14 is shown by a dashed line for ease of understanding.

[0051] The front projection 46 tapers in the front-rear direction toward the upper side, which is the protruding tip. In other words, the front projection 46 gradually widens in the front-rear direction toward the base end from the protruding tip. More specifically, the protruding tip of the front projection 46 is provided with a flat surface 48 that extends substantially perpendicular to the vertical direction, and a forward inclined surface 50 that slopes downward toward the front, continuous with the front of the flat surface 48, and a rearward inclined surface 52 that slopes downward toward the rear, continuous with the rear of the flat surface 48, so that the front projection 46 tapers in the front-rear direction toward the protruding tip. In this embodiment, the width dimension of the flat surface 48 in the front-rear direction is set to be 1 / 2 or less of the width dimension of the front projection 46 in the front-rear direction. The angle of inclination of the forward inclined surface 50 with respect to the vertically perpendicular plane is small relative to the rearward inclined surface 52. Preferably, the angle of inclination of the forward inclined surface 50 is 1 / 2 or less of the angle of inclination of the rearward inclined surface 52.

[0052] The connection between the flat surface 48 and the front and rear inclined surfaces 50 and 52 is a curved surface that is smoothly continuous, and the entire protruding tip surface (upper surface) of the tip projection 46, including the flat surface 48 and the front and rear inclined surfaces 50 and 52, has a smooth shape without corners. In this embodiment, the left and right sides of the tip projection 46 are planes that are substantially perpendicular to the left-right direction, and the upper surface and left and right sides of the tip projection 46 are connected in a way that forms corners, but the connection between the upper surface and left and right sides of the tip projection 46 can also be a curved surface that is smoothly continuous and has no corners. The left and right sides of the tip projection 46 do not necessarily have to be planes that are perpendicular to the left-right direction, and may be inclined and spread out with respect to a plane perpendicular to the left-right direction, or may be composed of curved surfaces. Specifically, for example, the left and right sides of the tip projection 46 may be inclined surfaces that approach each other toward the protruding tip side of the tip projection 46.

[0053] The front projection 46 is biased towards the rear because the flat surface 48 at the protruding tip is located behind the front-rear center of the front projection 46. The rear side of the front projection 46 protrudes more significantly upward than the front side relative to the front-rear center, and the average protrusion height on the rear side is greater than the average protrusion height on the front side. The volume of the front projection 46 is larger on the rear side relative to the front-rear center than on the front side. The center of gravity of the front projection 46 is set behind the center in the front-rear direction.

[0054] In this embodiment, the entire flat surface 48 is located behind the front-to-rear center of the front abutment projection 46. Also, in this embodiment, the entire flat surface 48 is located behind the center of the mounting hole 38. The flat surface 48 is located inward in the front-to-rear direction relative to the first mounting leg 42 and the second mounting leg 44 of the body-side bracket 14.

[0055] The protruding height dimension of the front abutment projection 46 is set so that when it comes into contact with the dash cross member 70 (described later), there is sufficient space for the wiring of the wire harness 72 (described later), that is, in this embodiment, the distance between the dash cross member 70 and the head of the fastening bolt 64 (described later). Accordingly, the protruding height dimension of the front abutment projection 46 is set appropriately, taking into consideration, for example, the outer diameter of the wire harness 72, the contact area and direction of the front abutment projection 46 with respect to the dash cross member 70, etc. For example, the protruding height of the front abutment projection 46 can be set so that, in the initial state of contact between the front abutment projection 46 and another member (dash cross member 70), the minimum distance between opposing members with the wire harness 72 in between (for example, the distance between the fastening bolt 64 and the dash cross member 70) is such that the wire harness 72 is not pinched. This ensures safety even when the wire harness 72 is wired alone without protective material such as corrugated tubing.

[0056] The body-side bracket 14, having the structure described above, is attached to the cylindrical vibration damping device 12. Specifically, the outer cylindrical member 18 of the cylindrical vibration damping device 12 is press-fitted and fixed into the mounting hole 38 of the body-side bracket 14, thereby fixing the body-side bracket 14 to the cylindrical vibration damping device 12 in an externally fitted state.

[0057] Furthermore, a motor-side bracket 54 is attached to the inner shaft member 16 of the cylindrical vibration damping device 12. The motor-side bracket 54 is made of a highly rigid material such as metal. As shown in Figures 1 to 3, the motor-side bracket 54 integrally comprises a motor mounting portion 56 which is fixed to an electric motor 68 (described later) and a pair of fixing arms 58 which extend from the motor mounting portion 56 and are fixed to both axial ends of the inner shaft member 16. The motor mounting portion 56 is a thick plate shape that widens substantially perpendicular to the front-rear direction, and multiple bolt holes 60 used for bolt fixing to the electric motor 68 are provided penetrating in the thickness direction of the plate. The pair of fixing arms 58 are provided so as to extend backward from both the left and right sides of the motor mounting portion 56. The upper and lower surfaces of the front part of the fixing arms 58 are inclined so as to approach each other toward the rear, and the upper and lower surfaces of the rear end are planar shapes that widen substantially perpendicular to the vertical direction. A bolt hole (not shown) that penetrates vertically is formed at the rear end of the fixed arm portion 58.

[0058] The motor-side bracket 54 is fixed to the inner shaft member 16 by having a pair of fixed arms 58, 58 that are superimposed on the fastening surfaces 26, 26 of a pair of bracket fastening parts 24, 24 on the inner shaft member 16 of the cylindrical vibration isolation device 12, and fastening bolts 64, 64 inserted through bolt holes (not shown) in the fixed arms 58, 58 being screwed into threaded holes (not shown) that open on the fastening surfaces 26, 26 of the bracket fastening parts 24, 24.

[0059] A pair of fixed arms 58, 58 are fixed to both axial ends of the inner shaft member 16, which is inserted through the mounting holes 38 of the body-side bracket 14, so that the interconnected motor-side bracket 54 and the inner shaft member 16 form a rectangular ring shape as a whole. This prevents the inner shaft member 16 and the motor-side bracket 54 from separating from the outer cylindrical member 18 and the body-side bracket 14. As a result, even if the pair of rubber arms 32, 32 of the main body rubber elastic body 20 break, relative separation of the inner shaft member 16 and the outer cylindrical member 18 is prevented. Thus, in this embodiment, a fail-safe mechanism that prevents relative separation of the inner shaft member 16 and the outer cylindrical member 18 is configured such that the axial ends of the inner shaft member 16, which is inserted through the mounting holes 38 of the body-side bracket 14, and both ends of the motor-side bracket 54, which is roughly U-shaped when viewed from above, are fixed together, preventing the inner shaft member 16 from coming out of the mounting holes 38. Furthermore, since the separation of the inner shaft member 16 and the outer cylindrical member 18 is prevented by the fail-safe mechanism, even if the main rubber elastic body 20 breaks due to, for example, a vehicle accident, the electric motor 68 (described later) attached to the motor-side bracket 54 is prevented from falling onto the road surface, thereby preventing damage to the electric motor 68 from falling onto the road surface.

[0060] As shown in Figures 2 and 3, the bracket-equipped vibration damping device 10 is mounted on an electric vehicle equipped with an electric motor 68 by attaching the body-side bracket 14, which is attached to the outer cylindrical member 18 of the cylindrical vibration damping device 12, to the vehicle body 66, and by attaching the inner shaft member 16 of the cylindrical vibration damping device 12 to the electric motor 68 via the motor-side bracket 54. Specifically, the lower surfaces of the first mounting leg 42 and the second mounting leg 44 of the body-side bracket 14 are superimposed on the upper surfaces of the mounting portions on the vehicle body 66, and the first and second mounting legs 42 and 44 and the vehicle body 66 are fixed to each other by bolts (not shown), thereby mounting the body-side bracket 14 to the vehicle body 66. Furthermore, the motor mounting portion 56 of the motor-side bracket 54 fixed to the inner shaft member 16 is superimposed on the electric motor 68, and the motor mounting portion 56 and the electric motor 68 are fixed to each other by bolts (not shown) inserted through bolt holes 60, thereby attaching the motor-side bracket 54 connected to the inner shaft member 16 to the electric motor 68. Note that the vehicle body 66 is not necessarily limited to the vehicle's main frame, but may be a subframe such as a suspension member attached to the main frame via a vibration damping device. In addition, the motor-side bracket 54 may be directly fixed to the electric motor 68, or it may be indirectly fixed via a mounting bracket on the electric motor 68 side.

[0061] The body-side bracket 14 is mounted on the vehicle body 66 with the central axis of the inner shaft member 16 of the cylindrical vibration damping device 12 oriented so that it extends in the left-right direction of the vehicle. Furthermore, when the bracket-equipped vibration damping device 10 is mounted on the vehicle, the front projection 46 of the body-side bracket 14 is biased toward the rear of the vehicle, and the motor-side bracket 54 extends from the inner shaft member 16 toward the front of the vehicle. In this description of the bracket-equipped vibration damping device 10, the up-down, front-rear, and left-right directions are substantially the same as the up-down, front-rear, and left-right directions of the vehicle.

[0062] When the bracket-equipped vibration damping device 10 is mounted on an electric vehicle, a dash cross member 70 is positioned above the bracket-equipped vibration damping device 10 as another component, as shown in Figure 5. The dash cross member 70 is located above the rear of the bracket-equipped vibration damping device 10. Note that in Figure 5, the dash cross member 70 is shown in a state where it is in contact with the body-side bracket 14 due to a vehicle accident or the like, but under normal circumstances, the dash cross member 70 is positioned above the body-side bracket 14.

[0063] Furthermore, a wire harness 72 is positioned between the fixed arm portion 58 of the motor-side bracket 54 and the dash cross member 70. The wire harness 72 consists of bundled insulated wires, such as those used for supplying power to the electric motor 68, with connectors attached to the ends of these insulated wires for connection to the electric motor 68, etc. A wiring space for the wire harness 72 is secured between the fixed arm portion 58 and the dash cross member 70 on the left side of the body-side bracket 14. In this wiring space, the wire harness 72 is routed without being strongly pressed against either the fixed arm portion 58 or the dash cross member 70, and more preferably, at a distance from both. The wire harness 72 is routed so as to extend upward from the rear to the front of the electric vehicle, sloping upward.

[0064] In the event of a vehicle collision or similar accident, the vehicle body 66 and the dash cross member 70 may be displaced closer together in the vertical direction. In this case, with the conventional bracket-type vibration damping device 100 shown in Figure 6, if the vehicle body 66 and the dash cross member 70 are displaced closer together until they are restricted by contact between the body-side bracket 14 and the dash cross member 70, the wiring space for the wire harness 72 formed between the fixing arm 58 of the motor-side bracket 102 and the dash cross member 70 becomes narrow, causing the wire harness 72 to be pinched between the fixing arm 58 and the dash cross member 70. As a result, there is a risk of malfunctions such as electrical leakage due to the wire harness 72 being broken. Note that in Figure 6, the wire harness 72 is crushed by the dash cross member 70, and the heads of the fixing arm 58 and fastening bolts 64 are embedded in the wire harness 72.

[0065] In contrast, in the vibration damping device 10 with bracket of this embodiment, when the vehicle body 66 and the dash cross member 70 are displaced closer in the vertical direction during a vehicle collision or the like, as shown in Figure 5, the forward-facing projection 46 that protrudes upward from the body-side bracket 14 comes into contact with the dash cross member 70 before other parts of the body-side bracket 14 and the wire harness 72. As a result of this forward contact between the forward-facing projection 46 and the dash cross member 70, the displacement between the vehicle body 66 and the dash cross member 70 is limited, ensuring that there is a sufficiently wide wiring space for the wire harness 72 provided between the fixed arm portion 58 of the motor-side bracket 54 and the dash cross member 70. Consequently, the wire harness 72 is prevented from being pinched between the fixed arm portion 58 and the head of the fastening bolt 64 and the dash cross member 70, thus avoiding risks such as electrical leakage due to wire harness 72 breakage.

[0066] Furthermore, the upper surface of the front end projection 46, on the side in front of the flat surface 48, is a forward-sloping surface 50 that slopes downward toward the front at a gentle angle, thereby ensuring space in front of the front end projection 46. Therefore, for example, if the wire harness 72 extending forward from the above-mentioned wiring space curves toward the back of the page in Figure 5, the front end projection 46 is less likely to interfere with the wiring of the wire harness 72.

[0067] The front abutment projection 46 is partially provided in the circumferential direction of the mounting cylinder portion 40 of the body-side bracket 14, and protrudes upward from the upper part of the mounting cylinder portion 40. Therefore, the body-side bracket 14 can be made smaller compared to the case where the front abutment projection is provided around the entire circumference of the mounting cylinder portion 40. In addition, since the front abutment projection 46 does not protrude to the left or right from the mounting cylinder portion 40 of the body-side bracket 14, space can be secured to the left and right sides of the front abutment projection 46 for arranging other components.

[0068] The front abutment projection 46 is predominantly located towards the rear of the vehicle. This prevents a decrease in space efficiency caused by the front abutment projection 46 being provided over an unnecessarily wide area, while allowing it to stably contact the dash cross member 70 located at the rear of the vehicle in the event of a vehicle accident. In this embodiment, the protruding tip surface (upper surface) of the front abutment projection 46 is composed of a flat surface 48 which is the tip surface of the largest protrusion, a forward inclined surface 50 with a small inclination angle that is continuous in front of the flat surface 48, and a rearward inclined surface 52 with a large inclination angle that is continuous behind the flat surface 48. This makes it easier to design the front abutment projection 46 to be predominantly located towards the rear of the vehicle.

[0069] In this embodiment, the front abutment projection 46 gradually increases in width in the front-rear direction from the protruding tip (upper end) towards the base end (lower side). With this shape of the front abutment projection 46 that widens in the front-rear direction toward the base end, high strength (load-bearing performance) can be obtained against the downward force input to the front abutment projection 46 due to contact with the dash cross member 70. In particular, the front abutment projection 46 in this embodiment is provided so as to protrude from substantially the entire upper surface of the mounting cylinder portion 40 of the body-side bracket 14, and since the cross-sectional area of ​​the base end is large, load-bearing performance against downward loads is more advantageously secured.

[0070] A flat surface 48 is provided at the protruding tip of the front abutment projection 46, and the flat surface 48 is primarily in contact with the dash cross member 70. This allows for a wider contact surface between the front abutment projection 46 and the dash cross member 70. In particular, in this embodiment, the contact surface (lower surface) of the dash cross member 70 with the front abutment projection 46 is an inclined surface that slopes upward toward the front of the vehicle. The greater the contact force between the front abutment projection 46 and the dash cross member 70, the further forward the dash cross member 70 contacts the flat surface 48, increasing the contact area and thus distributing the load according to the input load.

[0071] The upper surface of the front abutment projection 46 has a smooth circumferential shape in which the flat surface 48 and the front and rear inclined surfaces 50 and 52 are continuous curved surfaces. Therefore, when the dash cross member 70 comes into contact with the upper surface of the front abutment projection 46, the stress is distributed, and partial damage to the front abutment projection 46 and the dash cross member 70 is avoided.

[0072] The first and second mounting legs 42 and 44, which are the fixing parts of the body-side bracket 14 to the vehicle body 66, are provided at different positions separated from each other in the vehicle's longitudinal direction. Therefore, even if a downward load is applied to the front abutment projection 46, which is biased toward the rear of the vehicle, due to contact with the dash cross member 70, the rotational moment acting on the body-side bracket 14 is stably supported by the first and second mounting legs 42 and 44, making it difficult for the body-side bracket 14 to tilt toward the vehicle body 66 or for the fixing structure between the body-side bracket 14 and the vehicle body 66 to be damaged. In particular, in this embodiment, the contact portion of the front abutment projection 46 with the dash cross member 70 is located between the front and rear directions of the first and second mounting legs 42 and 44 in the vehicle's longitudinal direction, so the rotational moment due to contact between the rearward-biased front abutment projection 46 and the dash cross member 70 is stably supported by the first and second mounting legs 42 and 44.

[0073] Furthermore, since the body-side bracket 14 is fixed to the vehicle body 66 at multiple points in the front-rear direction of the vehicle by the first and second mounting legs 42 and 44, the body-side bracket 14 stably follows the deformation of the vehicle body 66 in the event of an electric vehicle accident. Therefore, the contact between the front projection 46 of the body-side bracket 14 and the dash cross member 70 ensures that a stable space for wiring the wire harness 72 is secured.

[0074] Although embodiments of the present invention have been described in detail above, the present invention is not limited by its specific description. For example, when a forward-projecting front stop projection is provided on the body-side bracket, the front stop projection may be partially provided on the upper surface of the body-side bracket on the rear side of the vehicle and not on the front side of the vehicle. In short, the front stop projection may be unevenly distributed on the rear side of the vehicle, for example, by being partially provided only on the rear side in the longitudinal direction of the vehicle.

[0075] The body-side bracket may be formed by separately molding a mounting cylinder portion that constitutes the wall of the mounting hole and a portion that is fixed to the vehicle body, and then post-fixing them by means of welding, bolting, adhesive, or other means.

[0076] It is desirable that the body-side bracket has two or more fixing points to the vehicle body, but one point is also acceptable. Furthermore, for example, if the overlapping surface of one mounting leg with the vehicle body has multiple screw holes at locations separated in the front-rear direction, and the mounting leg and the vehicle body are fixed by multiple mounting bolts screwed into these screw holes, then each location where a screw hole is formed on one mounting leg can be considered a fixing point. In short, having multiple fixing points does not necessarily mean that the structure is not limited to multiple fixing points that appear to be separate externally.

[0077] The vibration damping device attached to the body-side bracket is not limited to a cylindrical vibration damping device. For example, it may be a bowl-shaped vibration damping device in which a first mounting member and a cylindrical second mounting member, which are separated from each other in the vertical direction, are connected by a frustoconical main body rubber elastic body. In this case, the body-side bracket may have a structure that includes, for example, a cylindrical mounting cylinder portion into which the second mounting member is press-fitted and fixed, and a gate-shaped portion including a pair of mounting legs extending downward from the outer circumferential surface of the mounting cylinder portion. Furthermore, for example, by providing a front-end projection in the rebound stopper portion that connects a pair of lateral stopper portions extending upward from the pair of mounting legs at their upper ends, it is possible to prevent the wire harness from being pinched between the rebound stopper portion and other members such as the dash cross member.

[0078] The motor-side bracket may be fixed to only one end of the inner shaft member, either left or right, and extended outward to the left or right. In short, the arrangement of the vibration isolation device with bracket to the electric motor is not particularly limited and can be arranged, for example, on the left or right side of the electric motor. In addition, in the motor-side bracket 54 equipped with fixed arms 58, 58 extending forward from the inner shaft member 16 as in the first embodiment, if the mounting surface of the motor mounting portion 56 to the electric motor 68 is set to a direction other than forward, such as to the left or right side, it is possible to appropriately select the mounting direction of the motor-side bracket 54 to the electric motor 68 while keeping the direction of extension of the fixed arms 58, 58 from the inner shaft member 16 forward to avoid interference with the wire harness 72.

[0079] In the event of a vehicle accident, the protruding end of the body-side bracket may come into contact with other components, but this is not limited to the dash crossmember. [Explanation of Symbols]

[0080] 10. Vibration isolation device with bracket (first embodiment) 12. Cylindrical vibration isolation device 14 Body-side bracket 16 Inner shaft member 18 Outer cylindrical member 20 Main body rubber elastic body 22 Fixing part 24 Bracket fastening section 26 Fastening surface 28 First piercing hole 30 Second piercing hole 32 Rubber arm section 34 First Stopper Rubber 36 Second stopper rubber 38 mounting holes 40 Mounting cylinder part 42 First mounting leg 44 Second mounting leg 46. ​​Front protrusion 48 Flat surface 50 Front slope 52 Rear slope 54 Motor-side bracket 56 Motor mounting section 58 Fixed arm 60 bolt holes 64 fastening bolts 66 Vehicle Body 68 Electric motor 70 Dash cross member (other components) 72 Wire Harness 100 Vibration isolation device with bracket (comparative example) 102 Body-side bracket

Claims

1. A vibration damping device with a bracket for vibration-damping support of an electric motor relative to the vehicle body in an electric vehicle, It is equipped with a body-side bracket that is fixed to the vehicle body side, The body-side bracket is provided with fixing parts that are fixed to the vehicle body at multiple locations in the front-rear direction of the electric vehicle. The body-side bracket has a front projection that is located towards the rear of the electric vehicle and partially protrudes toward other components of the vehicle body. A vibration damping device with a bracket, wherein the protrusion height of the tip-contacting projection is set such that even when the tip-contacting projection is in contact with the other member on the vehicle body side, space for wiring a wire harness is secured between the other member on the vehicle body side and the tip-contacting projection.

2. The aforementioned body-side bracket is attached to a cylindrical vibration isolation device having a structure in which the inner shaft member and the outer cylindrical member are elastically connected by a main rubber elastic body. The bracket-equipped vibration damping device according to claim 1, wherein the cylindrical vibration damping device is mounted on the vehicle body with the central axis of the inner shaft member facing in the left-right direction of the vehicle.

3. The motor-side bracket is fixed to the inner shaft member with fastening bolts, The vibration isolation device with a bracket according to claim 2, wherein the body-side bracket is fixed to the outer cylindrical member in an externally fitted state.

4. The bracket-equipped vibration isolation device according to claim 3, wherein the aforementioned front abutment projection is provided so as to partially protrude on the outer circumferential surface of the body-side bracket.

5. In the body-side bracket, In the lower portion, the aforementioned fixing parts to the vehicle body are provided at multiple locations that differ in the front-rear direction of the vehicle, The bracket-equipped vibration damping device according to claim 4, wherein the upper portion has the aforementioned front-contacting projection formed to protrude and be biased toward the rear side of the vehicle.

6. The vibration isolation device with a bracket according to claim 2 or 3, which is provided with a fail-safe mechanism that prevents the relative separation of the inner shaft member and the outer cylindrical member even if the main body rubber elastic body breaks.

7. The aforementioned fail-safe mechanism is, The motor-side bracket is equipped with a pair of fixing arms that are fixed to both axial ends of the inner shaft member, which is inserted into the mounting hole of the body-side bracket. The vibration damping device with a bracket according to claim 6, wherein the inner shaft member is prevented from detaching from the mounting hole of the body-side bracket.

8. The motor-side bracket extends from the inner shaft member toward the front of the electric vehicle, The bracket-equipped vibration damping device according to claim 3 or 4, wherein the front abutment projection of the body-side bracket is located predominantly on the rear side of the electric vehicle.

9. The aforementioned tip projection widens from the protruding tip toward the base end, as described in claim 1 or 2 of the bracket-equipped vibration isolation device.

10. The aforementioned tip projection has a smooth surface shape with no corners overall, as described in claim 1 or 2.

11. The bracket-equipped vibration isolation device according to claim 1 or 2, wherein the aforementioned front abutment projection does not protrude laterally from the body-side bracket.

12. The aforementioned tip-contacting projection has a flat surface at its protruding tip, as described in claim 1 or 2, for the bracket-equipped vibration isolation device.

13. The bracket-equipped vibration isolation device according to claim 12, wherein the front side of the flat surface of the aforementioned front abutment projection is provided with a forward inclined surface having a smaller inclination angle than the rear side.

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