Electromagnetic noise suppressing structure for vehicle

Abstract

To provide an electromagnetic noise suppression structure for a vehicle capable of accurately suppressing radiation of noise without adding new wiring.SOLUTION: The electromagnetic noise suppressing structure for a vehicle includes the brake caliper 53 fixed to the knuckle 22 and configured to generate a braking force corresponding to a brake fluid pressure, and the brake hose 60 arranged inside the wheel house 4 and configured to transmit the brake fluid pressure supplied from the master cylinder 61 to the brake caliper 53, wherein the brake hose 60 has the braided wire 75 on the outer peripheral surface of the brake hose body 65, the braided wire 75 is conducted to the brake caliper 53 at the 65a of one end of the brake hose body 65, and the braided wire 75 is conducted to the vehicle body 2 at the 65b of the other end of the brake hose body 65.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention particularly relates to an electromagnetic noise suppression structure for a vehicle using an electric motor or the like as a drive source. [Background technology]

[0002] Conventionally, electric vehicles such as electric cars and hybrid cars have been known as vehicles that have an electric motor as a drive source. In such electric vehicles, high-frequency electromagnetic noise (hereinafter simply referred to as "noise") is induced in the rotor of the electric motor due to, for example, the on / off operation of a switching element in an inverter.

[0003] This noise is transmitted from the rotor to the drive shaft via gears. Furthermore, the noise from the drive shaft is transmitted to the steering knuckle (hereinafter simply referred to as the "knuckle"). This noise may be radiated from the knuckle to its surroundings. It is known that this noise may affect the reception of radio antennas mounted on the vehicle.

[0004] To address this issue, for example, Patent Document 1 (JP 2016-088297 A) discloses an electric vehicle that electrically connects the knuckle and the vehicle body using an earth harness. The electric vehicle of Patent Document 1 transmits noise transmitted to the knuckle to the vehicle body, thereby suppressing noise radiation. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-088297 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the earth harness in Patent Document 1 is a dedicated part that connects the knuckle to the vehicle body. Installing such an earth harness would increase the amount of work required to route the earth harness, potentially reducing work efficiency. In particular, the knuckle is subject to displacement due to road surface irregularities and steering during driving. Therefore, routing the earth harness to the knuckle in a way that prevents it from interfering with other components could significantly reduce work efficiency.

[0007] The present invention has been made in consideration of the above circumstances, and has an object to provide an electromagnetic noise suppression structure for a vehicle that can accurately suppress the radiation of electromagnetic noise without adding new wiring. [Means for solving the problem]

[0008] The present invention provides a braking force generating unit that is fixed to a steering knuckle and generates a braking force according to brake fluid pressure; a brake hose that is routed inside a wheel house and transmits the brake fluid pressure supplied from a master cylinder to the braking force generating unit; and the brake hose has a conductive layer on the outer surface of a brake hose body, the conductive layer being conducted to the braking force generating unit at one end of the brake hose body and the conductive layer being conducted to a vehicle body at the other end of the brake hose body. [Effects of the Invention]

[0009] According to the electromagnetic noise suppression structure for a vehicle of the present invention, radiation of electromagnetic noise can be suppressed accurately without adding new wiring. [Brief explanation of the drawings]

[0010] [Figure 1] Perspective view of a vehicle [Figure 2] Schematic diagram of the drive system, suspension system, and brake system of the vehicle, with the front wheels viewed from behind. [Figure 3] FIG. 1 is an enlarged perspective view showing a state in which a brake hose is routed inside a wheel house of a left front wheel of a vehicle. [Figure 4] FIG. 1 is an exploded perspective view showing the structure of the steering knuckle and its surroundings for the left front wheel of a vehicle. [Figure 5] Side view of the brake hose body with each layer exposed [Figure 6] FIG. 1 is an enlarged longitudinal cross-sectional view showing a state in which a first cap is fixed to one end of a brake hose body by crimping. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0012] In the drawings used in the following description, the scales of the components are different so that each component can be recognized easily. Therefore, the present invention is not limited to the number of components, the shapes of the components, the size ratios of the components, and the relative positions of the components shown in these drawings.

[0013] As an example of application of the electromagnetic noise suppression structure for a vehicle in this embodiment, the configuration of the drive, suspension, and braking systems for the front wheels of an electric vehicle 1 (hereinafter referred to as vehicle 1) equipped with an electric motor will be described.

[0014] As shown in Fig. 1, left and right wheels 3 are arranged in left and right wheel houses 4 at the front of a vehicle 1. Between these left and right wheels 3, as shown in Fig. 2, a drive unit 10, a suspension unit 20, and a brake unit 50 are arranged.

[0015] The drive system 10 includes a power unit 11, a power control unit 12, and a pair of drive shafts 13.

[0016] The power unit 11 includes, for example, an electric motor as a drive source and a transmission mechanism (neither of which are shown). The power unit 11 is connected to each of the left and right wheels 3 via drive shafts 13 for the wheels 3.

[0017] The power control unit 12 is for appropriately controlling the power of the vehicle 1. The power control unit 12 includes an inverter (not shown).

[0018] The inverter converts DC power supplied from a battery (not shown) of the vehicle 1 into AC power by turning on and off switching elements.

[0019] Then, power control unit 12 supplies the converted AC power to power unit 11. This causes the rotor of the electric motor to rotate.

[0020] The suspension device 20 in this embodiment is, for example, a strut-type suspension as shown in FIG.

[0021] The suspension device 20 and the surrounding area of ​​the suspension device 20 have a bilaterally symmetrical structure. Therefore, the left front side of the vehicle 1 will be described below.

[0022] The suspension device 20 includes a shock absorber 21, a steering knuckle 22, and a lower arm 23.

[0023] The shock absorber 21 includes a cylinder 21a and a piston rod 21b.

[0024] The piston rod 21b is inserted into and supported by the cylinder 21a, and is movable forward and backward relative to the cylinder 21a.

[0025] The shock absorber 21 is inserted into the coil spring 24 and extends in the vertical direction of the vehicle body.

[0026] The upper end of the piston rod 21b is attached to a strut tower 27 of the vehicle body 2 via a strut mount 26.

[0027] Here, the strut mount 26 is formed of an elastic body such as rubber, etc. Therefore, the upper end of the piston rod 21b is not electrically connected to the vehicle body 2.

[0028] The steering knuckle 22 (hereinafter referred to as the knuckle 22) is a component that supports the wheels 3 so that they can be steered. The knuckle 22 is, for example, a component made of cast iron that can withstand the load of supporting the wheels 3 so that they can be steered.

[0029] As shown in FIGS. 3 and 4, the knuckle 22 has a knuckle arm 30, a flange portion 32, a shaft insertion hole 33, and a hub unit attachment portion .

[0030] The knuckle arm 30 is formed to protrude from the upper part of the knuckle 22. The knuckle arm 30 is connected to the lower end of the cylinder 21a via a metal knuckle bracket 25. Therefore, the knuckle arm 30 and the cylinder 21a are electrically connected via the knuckle bracket 25.

[0031] The flange portion 32 extends toward the rear of the vehicle body and has a plurality of bolt insertion holes 35 (for example, two).

[0032] The shaft insertion hole 33 passes through the knuckle 22 in the vehicle width direction. An end of the drive shaft 13 is inserted into the shaft insertion hole 33.

[0033] The hub unit attachment portion 34 is formed around the shaft insertion hole 33 on the outer surface in the vehicle width direction.

[0034] A ball joint 36 protrudes from the lower end of the knuckle 22. The ball joint 36 is connected to a metal lower arm 23 (see FIG. 2). The connection between the ball joint 36 and the lower arm 23 is liquid-tight sealed by a rubber lower arm boot (not shown) filled with lubricant.

[0035] The lower arm 23 supports the knuckle 22 and is connected to an end of a suspension cross member 37 that extends in the vehicle width direction as a subframe of the vehicle body 2 (see FIG. 2). The lower arm 23 and the suspension cross member 37 are connected via a rubber bushing (not shown). Therefore, the lower arm 23 is not electrically connected to the vehicle body 2.

[0036] A hub unit 29 is provided on the outer side of the knuckle 22 in the vehicle width direction.

[0037] The hub unit 29 is a component that supports the wheel 3 so that the wheel 3 can rotate about its central axis. The hub unit 29 is a metal component. The hub unit 29 integrally includes a hub body 40 and a hub bearing 41.

[0038] The hub body 40 is formed in a disk shape. A plurality of bolts 43 (for example, four bolts) for attaching the wheel 3 are provided on the hub body 40 so as to protrude outward in the vehicle width direction.

[0039] The hub body 40 also has a cylindrical rotating shaft 42 that protrudes inward in the vehicle width direction from the center of the hub body 40. A serrated hole 42a is formed inside the rotating shaft 42. An end of the drive shaft 13 is inserted into the serrated hole 42a.

[0040] Here, the end of the drive shaft 13 is formed with a serration portion 13a and a threaded portion 13b.

[0041] The serration portion 13a is inserted into the serration hole 42a and engaged with the serration hole 42a. In this state, a nut 45 is threaded onto the threaded portion 13b. This fixes the end of the drive shaft 13 to the hub body 40.

[0042] The hub bearing 41 rotatably supports the hub body 40. The hub bearing 41 has a flange portion 44.

[0043] The flange portion 44 is fixed to the hub unit attachment portion 34 using a plurality of bolts (for example, four bolts) not shown.

[0044] With this configuration, the hub unit 29 is fixed to the knuckle 22 in a state of electrical continuity with the drive shaft 13.

[0045] The brake device 50 of this embodiment is, for example, a disc brake, as shown in FIGS.

[0046] Such a braking device 50 has a disc rotor 52 and a brake caliper 53 as a braking force generating section.

[0047] The disc rotor 52 is formed in a disk shape. A central portion of the disc rotor 52 protrudes outward in the vehicle width direction. A plurality of holes 52a (for example, four holes) are formed in the central portion of the disc rotor 52 at positions corresponding to the plurality of bolts 43.

[0048] Such a disc rotor 52 is attached to the hub body 40 with a plurality of bolts 43 inserted into a plurality of holes 52a.

[0049] The brake caliper 53 is a metal component and is disposed, for example, at the rear of the vehicle body so as to cover a portion of the disc rotor 52.

[0050] 4, the mounting portion 54 is provided at a position facing the flange portion 32. Furthermore, the mounting portion 54 is provided with a plurality of bolt holes 55 (for example, two) at positions corresponding to the plurality of bolt insertion holes 35 (for example, two).

[0051] As a result, the mounting portion 54 is in contact with the flange portion 32 with the plurality of bolt holes 55 positioned in the plurality of bolt insertion holes 35. The mounting portion 54 is then fixed to the flange portion 32 with a plurality of bolts (for example, two) not shown. The brake caliper 53 is fixed to the knuckle 22 by this mounting portion 54. Therefore, the brake caliper 53 and the knuckle 22 are electrically connected.

[0052] The brake fluid introduction portion 56 is provided, for example, on the inner side in the vehicle width direction of the brake caliper 53. The brake fluid introduction portion 56 is supplied with brake fluid pressure.

[0053] By supplying the brake fluid pressure in this manner, the brake caliper 53 generates a braking force according to the brake fluid pressure.

[0054] Here, the brake fluid pressure supplied to the brake fluid introduction portion 56 can be supplied from a master cylinder 61 .

[0055] In order to transmit such brake fluid pressure from the master cylinder 61 to the brake caliper 53, a brake pipe 62 and a brake hose 60 are provided between the master cylinder 61 and the brake caliper 53.

[0056] 2, the brake pipe 62 constitutes a brake fluid pressure supply path in the section from the master cylinder 61 to the wheel house 4. For this reason, the downstream end of the brake pipe 62 is fixed to a metal inner wall 63 of the wheel house 4.

[0057] Here, the inner wall 63 is provided with a bracket 86 for fixing to the vehicle body for fixing the downstream end of the brake pipe 62.

[0058] The bracket 86 for fixing to the vehicle body has a shape obtained by bending a metal flat plate into an L shape, for example. One end of the bracket 86 for fixing to the vehicle body is fixed to the inner wall 63 by welding or the like. Therefore, the bracket 86 for fixing to the vehicle body is electrically connected to the vehicle body 2.

[0059] The brake hose 60 constitutes a brake fluid pressure supply path in the section from the inner wall 63 of the wheel house 4 to the brake caliper 53. In other words, the brake hose 60 is routed inside the wheel house 4.

[0060] Incidentally, the power unit 11 generates high-frequency electromagnetic noise (hereinafter simply referred to as "noise") due to the on / off operation of switching elements in the inverter, etc. Such noise is transmitted from the power unit 11 to the knuckle 22 via the drive shaft 13. The noise is further transmitted to the knuckle 22 and the like.

[0061] As described above, the upper end of the piston rod 21b of the shock absorber 21 and the lower arm 23 are insulated from the vehicle body 2. Therefore, noise transmitted to the knuckle 22 and the like is radiated without being grounded to the vehicle body 2.

[0062] In order to suppress the radiation of such noise, the brake hose 60 has the function of grounding the brake caliper 53 to the vehicle body 2. The structure of the brake hose 60 for realizing the grounding function will be described below.

[0063] The brake hose 60 has a brake hose body 65 , a first connector 66 , and a second connector 67 .

[0064] The brake hose body 65 is constructed to withstand brake fluid pressure, and is therefore formed by laminating multiple layers of rubber material and fiber threads.

[0065] 5, the brake hose body 65 has an inner tube rubber layer 68, a lower thread layer 69, an intermediate rubber layer 70, an upper thread layer 71, and an outer sheath rubber layer 72. The inner tube rubber layer 68, the lower thread layer 69, the intermediate rubber layer 70, the upper thread layer 71, and the outer sheath rubber layer 72 are layered in this order from the radially inner side (lower layer side).

[0066] The brake hose 60 of this embodiment has a braided wire 75 on the outer circumferential surface of the brake hose body 65 .

[0067] Braided wire 75 is formed by braiding conductive metal wires. For example, the metal wires that make up braided wire 75 are made of copper, aluminum, or the like. As a result, brake hose 60 has a conductive layer on the outside of brake hose body 65.

[0068] The first connector 66 is provided at one end 65a of the brake hose body 65. The second connector 67 is provided at the other end 65b of the brake hose body 65. The first connector 66 and the second connector 67 are made of, for example, an aluminum alloy.

[0069] As shown in Fig. 6, each of the first and second nozzles 66, 67 has a joint portion 76, a nipple portion 77, and a socket portion 78. The first and second nozzles 66, 67 have substantially the same configuration. Therefore, only the first nozzle 66 will be described below, and a description of the second nozzle 67 will be omitted.

[0070] The joint portion 76 functions as a connection portion when connecting to the brake fluid introduction portion 56 .

[0071] The nipple portion 77 extends cylindrically from the joint portion 76 toward the brake hose body 65. A socket portion 78 is provided on the outer periphery of the nipple portion 77 at a distance.

[0072] One end 65 a of the brake hose body 65 together with the braided wire 75 is inserted between the nipple portion 77 and the socket portion 78 .

[0073] Then, the first mouthpiece 66 is firmly fixed to the one end 65a of the brake hose body 65 via the braided wire 75 by crimping 80 from the radially outer side of the socket portion 78.

[0074] With this configuration, the first and second mouthpieces 66, 67 are fixed to the opposite ends 65a, 65b of the brake hose body 65 in a state in which they are electrically connected to the braided wire 75.

[0075] That is, the first and second bases 66 and 67 are electrically connected to each other via the braided wire 75 .

[0076] The first nozzle 66 is connected to the brake fluid introduction portion 56 of the brake caliper 53. On the other hand, the second nozzle 67 is fixed to a bracket 86 for fixing to the vehicle body in a state where it is connected to the brake pipe 62.

[0077] Such connection of the first and second mouthpieces 66, 67 provides electrical continuity between the brake caliper 53 and the vehicle body 2.

[0078] Here, the middle portion of the brake hose 60 is fixed to the knuckle bracket 25 .

[0079] For this reason, a wiring bracket 85 is disposed on the knuckle bracket 25 as a bracket for fixing the intermediate portion of the brake hose 60 .

[0080] The wiring bracket 85 has a shape obtained by bending a metal flat plate into an L shape, for example. One end of the wiring bracket 85 is fixed to the knuckle bracket 25 by welding, for example. Therefore, the wiring bracket 85 is electrically connected to the knuckle 22 via the knuckle bracket 25.

[0081] By means of this routing bracket 85, the intermediate portion of the brake hose 60 is fixed to the knuckle bracket 25 and is conducted to the knuckle 22.

[0082] According to this embodiment, the vehicle electromagnetic noise suppression structure includes a brake caliper 53 that is fixed to the knuckle 22 and generates a braking force according to brake fluid pressure, a brake hose 60 that is routed inside the wheel house 4 and transmits brake fluid pressure supplied from a master cylinder 61 to the brake caliper 53, and the brake hose 60 has a braided wire 75 on the outer peripheral surface of a brake hose body 65, with the braided wire 75 being conducted to the brake caliper 53 at one end 65a of the brake hose body 65 and the braided wire 75 being conducted to the vehicle body 2 at the other end 65b of the brake hose body 65. With this configuration, noise radiation can be appropriately suppressed without adding any new wiring.

[0083] That is, the outer peripheral surface of the brake hose main body 65 is covered with a braided wire 75 serving as a conductive layer. At both end portions 65a, 65b of the brake hose main body 65, the braided wire 75 is electrically connected to the brake caliper 53 and the vehicle body 2, respectively. This allows the brake hose 60 to accurately transmit noise transmitted from the power unit 11 to the knuckle 22, etc., from the brake caliper 53 to the vehicle body 2. In this way, adding the function of a ground wire to the brake hose 60 makes it possible to suppress noise radiation without adding new wiring.

[0084] Additionally, the brake hose 60 has a first connector 66 at one end 65a of the brake hose body 65. Furthermore, the brake hose 60 has a second connector 67 at the other end 65b of the brake hose body 65. These first and second connectors 66, 67 are fixed to both end portions 65a, 65b of the brake hose body 65 in a state in which they are electrically connected to the braided wire 75. This makes it possible to achieve electrical continuity between the knuckle 22 side and the vehicle body 2 side simply by connecting the brake hose 60 to supply brake fluid pressure to the brake caliper 53.

[0085] Moreover, each of the first and second mouthpieces 66, 67 is fixed to the brake hose body 65 via the braided wire 75 by crimping 80. This allows the first and second mouthpieces 66, 67 to be electrically connected to the braided wire 75 without adding a new process when assembling the brake hose 60. Furthermore, the crimping 80 of the first and second mouthpieces 66, 67 allows the first and second mouthpieces 66, 67 and the braided wire 75 to be firmly connected to each other.

[0086] Furthermore, a middle portion of the brake hose 60 is fixed by a metal routing bracket 85 arranged at a position where it is connected to the knuckle 22. Furthermore, the routing bracket 85 is connected to the braided wire 75. As a result, the middle portion of the brake hose 60 is connected to the knuckle 22 via the routing bracket 85. Therefore, compared to a case where the routing bracket 85 is not arranged, the brake hose 60 can more accurately transmit noise transmitted to the knuckle 22 to the vehicle body 2.

[0087] In this embodiment, an example has been described in which braided wire 75 is applied to the outer surface of brake hose main body 65 as a conductive layer, but the present invention is not limited to braided wire 75 and can be applied to any bendable conductive material.

[0088] Furthermore, in order to protect the braided wire 75 (conductive layer), a protective layer made of a rubber material or the like may be provided on the outer circumferential surface of the brake hose 60. When such a protective layer is provided on the brake hose 60, a portion of the coating of the midsection of the brake hose 60 that is connected to the routing bracket 85 is removed.

[0089] The invention described in the above embodiments is not limited to these forms, and various modifications can be made in the implementation stage without departing from the spirit of the invention.

[0090] Furthermore, the above-mentioned embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining the multiple constituent elements disclosed.

[0091] Furthermore, even if some of the constituent elements are deleted from all the constituent elements shown in the above embodiment, if the stated problem can be solved and the stated effect can be obtained, the configuration from which these constituent elements are deleted can be extracted as an invention. [Explanation of symbols]

[0092] 1. Electric vehicle (vehicle) 2. Body 3...wheels 4. Wheelhouse 10. Drive unit 11. Power unit 12 Power control unit 13. Drive shaft 13a Serration section 13b...Threaded part 20. Suspension device 21. Shock absorber 21a···Cylinder 21b Piston rod 22···Steering knuckle (knuckle) 23 Lower arm 24···Coil spring 25···Knuckle bracket 26···Strut mount 27···Strut tower 29 Hub unit 30···Knuckle arm 32 Flange part 33 Shaft insertion hole 34 Hub unit mounting section 35 Bolt insertion hole 36. Ball joint 37···Suspension cross member 40 Hub body 41 Hub bearing 42 Rotation axis 42a Serrated hole 43 volts 44 Flange part 45···Nut 50 Brake device 52···Disc rotor 52a Bolt insertion hole 53 Brake caliper 54 Mounting part 55 Bolt hole 56 Brake fluid inlet 60···Brake hose 61 Master cylinder 62 Brake pipe 63...inner wall 65···Brake hose body 65a...One end 65b...Other end 66···First nozzle 67 Second nozzle 68...Inner tube rubber layer 69...Bobbin thread layer 70···Middle rubber layer 71...Needle thread layer 72 Outer rubber layer 75···Braided wire (conductive layer) 76···Joint part 77 Nipple part 78···Socket part 80···Crimping 85···Routing bracket 86···Body fixing bracket

Claims

1. a braking force generating unit fixed to the steering knuckle and configured to generate a braking force in accordance with brake fluid pressure; a brake hose that is routed inside a wheel house and transmits the brake fluid pressure supplied from a master cylinder to the braking force generating unit; The brake hose has a conductive layer on the outer circumferential surface of the brake hose body, At one end of the brake hose body, the conductive layer is electrically connected to the braking force generating section, The electromagnetic noise suppression structure for a vehicle is characterized in that the conductive layer at the other end of the brake hose body is electrically connected to the vehicle body.

2. a first connector fixed to the one end of the brake hose body and electrically connectable to the braking force generating unit; a second connector fixed to the other end of the brake hose body and electrically connectable to the vehicle body, 2. The electromagnetic noise suppression structure for a vehicle according to claim 1, wherein the first cap and the second cap are electrically connected to the conductive layer.

3. 3. The electromagnetic noise suppression structure for a vehicle according to claim 2, wherein the first and second connectors are fixed to the brake hose body by crimping via the conductive layer.

4. a metal bracket disposed at a position where the brake hose is connected to the steering knuckle and fixes a middle portion of the brake hose; 2. The electromagnetic noise suppression structure for a vehicle according to claim 1, wherein the bracket is electrically connected to the conductive layer.

5. 2. The electromagnetic noise suppression structure for a vehicle according to claim 1, wherein the conductive layer is a braided wire.

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