JP2009029218A - Shielding member and mobile body provided with shielding member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shield or reduce electromagnetic noise to be a factor of radio noise. <P>SOLUTION: This shielding member 50 shields the electromagnetic noise transmitted and radiated from an inverter to be a noise generation source to a drive shaft 24. The shielding member 50 includes a drive shaft shielding material 38 provided to cover the drive shaft 24. More preferably, the shielding member 50 further includes a cable shielding material 34 provided to cover a cable 18 and a motor shielding material 36 provided to cover a motor 20. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a shielding member and a movable body including the shielding member.

  In order to prevent radio wave interference to the human body and other electrical devices due to electromagnetic waves emitted from electrical devices, electrical devices that may cause radio interference are preliminarily surrounded by a shielding material such as a metal plate. A method of shielding is known. Similarly, in electrical equipment mounted on moving bodies such as automobiles, it is required to suppress malfunctions of the moving body itself due to electromagnetic waves, etc., and the influence on the human body and other electrical equipment. It has been adopted.

  Patent Document 1 discloses a body frame and a drive shaft connected to a tire wheel, in order to prevent the body frame from causing a potential difference with respect to the ground due to an electric device installed on the body frame of the electric vehicle. It is described that it is electrically connected and grounded through a conductive tire.

  Patent Document 2 describes an electric vehicle that includes a cabin with a shielding material and shields electromagnetic waves generated from a motor, a cable, and the like.

  FIG. 3 illustrates an outline of a general configuration of an electric vehicle. The electric vehicle 300 shown in FIG. 3 converts a direct current obtained from the chargeable / dischargeable battery 12 into an alternating current by the inverter 16, adjusts it to a desired output by a control unit (not shown), and rotates the motor 20. The motor 20 has a rotation shaft (not shown) connected to the drive shaft 24 of the rear wheel 26, and the rotation of the rotation shaft by the motor 20 is transmitted to the drive shaft 24 via the differential device 22, thereby the rear wheel 26. Is configured to run while rotating.

  In FIG. 3, the motor 20 generally serves also as a generator, and is configured such that electric power generated when braking power is input to a rotating shaft (not shown) is charged to the battery 12 via the inverter 16. . As another form, the motor 20 and the differential 22 can be integrated. In FIG. 3, the differential device 22 is incorporated in the motor 20. However, as another embodiment, the differential device 22 may be separated.

  On the other hand, in general, a hybrid vehicle is provided with an internal combustion engine such as an engine (not shown) in addition to the configuration of the electric vehicle 300 shown in FIG.

  4 is an overall view illustrating the arrangement of the inverter 16, the motor 20, and the drive shaft 24 in the electric vehicle 300 shown in FIG.

  In FIG. 4, the inverter 16 is fixed to the vehicle body frame 30 or the vicinity thereof, and serves as a noise generation source that generates and radiates electromagnetic noise by switching the inverter circuit when the electric vehicle 300 is operated.

  A technique for preventing the generation of radio noise due to electromagnetic noise radiation to the radio antenna 40 by shielding the inverter 16 and the cable 18 and the motor 20 electrically connected to the inverter 16 is disclosed (for example, patents). References 3, 4).

  In Patent Document 3, in the electric system of an electric vehicle, in order to reduce the high-frequency leakage current flowing between the vehicle-mounted electric device and the cable that electrically connects them and the vehicle body, a storage frame for each electric device is provided. It describes that it is electrically insulated from the vehicle body.

  Patent Document 4 describes that a metal cover that shields electromagnetic waves is provided around a cable portion that is electrically connected to an electrical device to shield electromagnetic waves emitted from the cable portion.

  However, according to the inventions described in Patent Documents 3 and 4, it seems that electromagnetic noise radiated from electrical devices and cables electrically connected thereto can be shielded. For example, it is still insufficient for removing electromagnetic noise radiated to the radio antenna 40 that affects reception of a vehicle-mounted radio or the like.

JP 9-168207 A JP 2002-291113 A JP-A-8-98328 JP-A-2005-68716

  By the way, in the electric vehicle described in Patent Document 1, as described above, the shielding of the radiated electromagnetic noise is not considered. Moreover, in patent document 2, since it is necessary to provide a shielding material for the whole cabin depending on the size of an electric device to be mounted and the arrangement of cables, the material cost becomes a problem in some cases.

  The present invention shields electromagnetic noise that may cause radio noise by being propagated and radiated from noise generation sources such as electric devices mounted on a moving body such as an electric vehicle or a hybrid vehicle to each member. The purpose is to reduce.

  The configuration of the present invention is as follows.

  (1) A shielding member that shields electromagnetic noise that is propagated and radiated from a noise generation source to the drive shaft.

  (2) The said shielding member is a shielding member as described in said (1) containing the drive shaft shielding material provided so that the said drive shaft may be covered.

  (3) In the shielding member according to (2), at least a cable and a motor are provided between the noise generation source and the drive shaft, and are propagated and radiated from the noise generation source to the cable. A cable shielding material provided so as to cover the cable in order to shield electromagnetic noise, and a motor provided so as to cover the motor in order to shield electromagnetic noise transmitted from the noise generation source to the motor and radiated. A shielding member further comprising a shielding material.

  (4) The shielding member according to (3), wherein the drive shaft shielding material, the cable shielding material, and the motor shielding material are integrally formed.

  (5) The shielding member according to any one of (1) to (4), wherein the noise generation source includes an inverter.

  (6) A moving body comprising the shielding member according to any one of (1) to (5) above.

  (7) In the moving body according to (6), the noise generation source is fixed to the moving body frame or the vicinity thereof, and the conductive body is suspended from the moving body frame and attached to the drive shaft. A moving object including a medium.

  (8) The moving body according to (7), wherein the conductive medium has an annular portion, and the drive shaft is inserted through the annular portion.

  (9) The moving body according to any one of (5) to (8), wherein the moving body is an electric vehicle or a hybrid vehicle.

  According to the present invention, it is possible to prevent or reduce radio noise.

  In the electric vehicle 300 shown in FIGS. 3 and 4, the electromagnetic noise generated in the inverter 16 propagates not only to the cable 18 and the motor 20 but also to the drive shaft 24 via the differential device 22. The electromagnetic noise radiated from the drive shaft 24 easily reaches the radio antenna 40 and generates radio noise.

  As a means for easily removing electromagnetic noise radiated from an apparatus fixed at a predetermined position, there is a method of contacting the body frame 30 or the like via a conductive member. However, since the drive shaft 24 is a rotating member, it is difficult to bring a conductive member into direct contact with the drive shaft 24. Therefore, for example, a method such as shown in FIG. It is conceivable to perform the removal. That is, in FIG. 5, a conductive material such as a copper wire is provided between the motor 20 and / or the differential 22 (see FIG. 3), which is a device fixed at a position relatively close to the drive shaft 24, and the vehicle body frame 30. The electromagnetic member radiated from the drive shaft 24 and the vicinity thereof can be removed by connecting the sex members 42.

  According to the electric vehicle 400 having the configuration illustrated in FIG. 5, a certain degree of effect is exhibited in the removal of electromagnetic noise, and compared with the case where the conductive member 42 is not used, the frequency of occurrence of radio noise and / or The degree is reduced. However, complete and / or effective removal of radio noise has nevertheless been difficult.

  In the following, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected about the same location as what was shown in FIGS. 3-5, and the description is abbreviate | omitted.

  FIG. 1 shows an outline of the configuration of the electric vehicle 100 according to the embodiment of the present invention, particularly the motor 20, the drive shaft 24, and the vicinity thereof. The electric vehicle 100 shown in FIG. 1 is provided with a conductive medium 32 that is suspended from the vehicle body frame 30 and attached to the drive shaft 24 instead of the conductive member 42 of FIG. The configuration of the electric vehicle 400 shown in FIG.

  In the present embodiment, the conductive medium 32 is suspended from the vehicle body frame 30 located in the vicinity of the drive shaft 24. In particular, the configuration in which the drive shaft 24 is arranged in the vertical direction of the connection portion 31 between the vehicle body frame 30 and the conductive medium 32 is preferable because the size of the conductive medium 32 can be further reduced. is there. At this time, the connection between the vehicle body frame 30 and the conductive medium 32 in the connection portion 31 may be any configuration as long as electrical connection is possible. And the like. In addition, although the distance between the vehicle body frame 30 and the drive shaft 24 changes with shapes of the electric vehicle 100, it is about 20-50 cm, for example.

  Further, in FIG. 1, the conductive medium 32 always follows the rotating drive shaft 24, for example, even during running, and can stably hold the attached state. In addition, it is also preferable that an annular portion 33 as shown in FIG. 1 is provided in a part of the conductive medium 32 and the drive shaft 24 is inserted through the annular portion 33. At this time, it is also preferable to set the dimensions of the conductive medium 32 so that the drive shaft 24 always has a predetermined tension with respect to the annular portion 33 of the conductive medium 32.

  Furthermore, it is preferable that the width of the conductive medium 32 (annular portion 33) is, for example, about 20 mm to 40 mm so as to ensure a predetermined contact area between the drive shaft 24 and the conductive medium 32. Further, in order to make the contact between the drive shaft 24 and the conductive medium 32 more reliable, for example, a plurality of conductive media 32 (for example, about two to three) are attached to one drive shaft 24. It is also suitable. In FIG. 1, the conductive medium 32 is shown as inserted through only one of the drive shafts 24 (right rear as viewed in FIGS. 3 and 4), but the conductive medium 32 corresponds to both the left and right drive shafts 24. Each medium 32 may be provided, and can be set as appropriate according to the position and sensitivity of the radio antenna 40 shown in FIG.

  In the present embodiment shown in FIG. 1, the conductive medium 32 and the drive shaft 24 are, for example, in the case where they are constantly rubbed while receiving a predetermined pressure with each other. It is preferred that 32 has a predetermined wear resistance. By applying the conductive medium 32 having a predetermined wear resistance, it is possible to prevent or suppress a decrease in the radiation noise removal performance accompanying wear deterioration of the conductive medium 32. At this time, for example, the annular portion 33 of the conductive medium 32 that can be rubbed with the drive shaft 24 is made to have a thickness of, for example, about 2 to 5 mm, and the deterioration of the conductive medium 32 due to the thinning is suppressed, or the conductive medium 32. It is also preferable to improve the wear resistance by reducing the surface roughness at the mounting portion between the drive shaft 24 and the drive shaft 24, or by using a substrate as shown below.

  In the present embodiment, examples of the base material that can be suitably used as the conductive medium 32 include a rubber material or a resin material having desired flexibility and elasticity. As the base material having such characteristics, Examples thereof include nitrile rubber, ethylene propylene rubber, acrylic rubber, silicone rubber, epoxy resin, and polyester resin. In particular, silicone rubber is suitable because it has desired elasticity and wear resistance.

  In the present embodiment, the preferable “conductivity” of the conductive medium 32 is not particularly limited as long as the electromagnetic noise propagated to the drive shaft 24 can be effectively removed. Is not to be done. For example, the conductive medium 32 is actually provided on the moving body, the noise generation source is actually operated to perform sensory evaluation (audience evaluation), and pass / fail is determined based on not perceiving noise. However, the conductive medium 32 can be manufactured, but is not limited thereto. In addition, a method for producing the conductive medium 32 having desired conductivity is not particularly limited, and the conductive medium 32 may be produced by any method, and is made of copper, aluminum, zinc oxide, carbon black, or the like. A conductive particle having an average particle diameter of about 10 to 100 μm is formed by dispersing a predetermined amount (for example, about 30 to 50 parts by weight with respect to 100 parts by weight of the base material) in the above base material. It is possible to exemplify those obtained by attaching or applying a conductive thin film made of a metal material such as copper, aluminum, zinc, or nickel on the surface of the material material.

  FIG. 2 shows an outline of the configuration of the electric vehicle 200 according to another embodiment of the present invention, particularly the motor 20, the drive shaft 24, and the vicinity thereof. The electric vehicle 200 shown in FIG. 2 is provided with a shielding member 50 that shields electromagnetic noise that is propagated and radiated from the inverter 16 (see FIG. 4) instead of the member 42 of FIG. The configuration of the electric vehicle 400 shown in FIG.

  The shielding member 50 shown in FIG. 2 includes a drive shaft shielding member 38 provided so as to cover the drive shaft 24. The drive shaft shielding member 38 is formed on at least a part of a drive shaft cover (a protective member made of a resin molding or the like covering the outer peripheral portion of the drive shaft 24) not shown in FIGS. It is preferable that a shield structure such as a metal mesh metal layer is provided so that electromagnetic noise radiated from the drive shaft 24 toward at least the radio antenna 40 (FIG. 4) can be shielded. At this time, for example, copper, aluminum, zinc, nickel or the like can be used as a shielding structure such as a metal thin film layer or a wire mesh metal layer provided on at least a part of the drive shaft shielding member 38 (drive shaft cover). is there. In another embodiment, the drive shaft shielding member 38 can be a separate member from the drive shaft cover.

  Further, the shielding member 50 shown in FIG. 2 preferably further includes a cable shielding material 34 provided so as to cover the cable 18. The cable shielding member 34 covers at least a part of the cable 18 with a cable cover provided with a shielding structure such as a metal thin film layer or a wire mesh metal layer, and faces at least the radio antenna 40 (FIG. 4) from the cable 18. It is preferable to adopt a configuration capable of shielding radiated electromagnetic noise. In another embodiment, a shielded cable having a desired shield performance can be used in advance.

  The shielding member 50 shown in FIG. 2 also preferably includes a motor shielding material 36 provided to cover the motor 20. As the motor shielding member 36, at least a part of a housing (also referred to as a motor cover) that houses a motor portion is provided with a shielding structure such as a metal thin film layer or a wire mesh metal layer, and at least a radio antenna 40 (see FIG. It is preferable to adopt a configuration capable of shielding electromagnetic noise radiated toward 4).

  Thus, the shielding member 50 shown in FIG. 2 is propagated from the inverter 16 (FIG. 4) and radiated from each member (drive shaft 24, cable 18 and motor 20) toward the radio antenna 40 (FIG. 4). Shields electromagnetic noise.

  Further, as another embodiment of the present invention, when the shielding member 50 shown in FIG. 2, that is, the drive shaft shielding material 38, the cable shielding material 34, and the motor shielding material 36 are integrally formed, assembly is easy. In addition, the number of parts can be reduced as compared with the case where a shielding material is provided independently, which is preferable.

  As described above, the shielding member 50 shown in FIG. 2 shields at least electromagnetic noise radiated toward the radio antenna 40 (FIG. 4) and can be any configuration that can remove or reduce radio noise. Things may be applied. That is, in FIG. 4, it is not necessary to cover the entire circumference of the drive shaft 24, the cable 18, and the motor 20, and it is not necessary to provide a shielding structure over the entire shielding member 50 (FIG. 2). Regarding the shape of the shielding member 50 and the location where the shielding structure is applied, the positional relationship and distance between the drive shaft 24, the cable 18 and the motor 20 and the radio antenna 40, the sensitivity of the radio antenna 40, and the electromagnetic wave radiated from each member. It can also be influenced by the intensity of noise. That is, the detailed configuration of the shielding member 50 can be appropriately set together with the design of the electric vehicle 200 shown in FIG.

  The conductive medium 32 shown in FIG. 1 and the shielding member 50 shown in FIG. 2 are arranged on the rear side similar to that of the radio antenna 40 (the rear side shown in FIG. 4) according to the arrangement location of the radio antenna 40 (FIG. 4). Although it is arranged on the wheel 26 side, the present invention is not limited to this. For example, it can be arranged on the front side (front wheel 28 side shown in FIG. 4). Further, the same or different conductive medium 32 (FIG. 1) or shielding member 50 (FIG. 2) may be provided on both the rear wheel 26 side and the front wheel 28 side shown in FIG. It is also possible to combine the configurations as shown.

  The present invention can be used not only in an electric vehicle but also in a hybrid vehicle or any other mobile body in which radio noise may be generated due to radiated electromagnetic noise.

It is the figure which showed the outline of the structure of the electric vehicle in embodiment of this invention. It is the figure which showed the outline of the structure of the electric vehicle in other embodiment of this invention. An outline of a general configuration of an electric vehicle is illustrated. FIG. 4 is an overall view illustrating the arrangement of the inverter 16, the motor 20 and the drive shaft 24 in the electric vehicle shown in FIG. 3. 2 is a diagram showing an outline of the configuration of an electric vehicle 400. FIG.

Explanation of symbols

  12 Battery, 14, 18 Cable, 16 Inverter, 20 Motor, 22 Actuator, 24 Drive shaft, 26 Rear wheel, 28 Front wheel, 30 Body frame, 32 Conductive medium, 33 Annular part, 34 Cable shield, 36 Motor shield Material, 38 drive shaft shielding material, 40 radio antenna, 50 shielding member, 100, 200, 300, 400 electric vehicle.

Claims (9)

  A shielding member that shields electromagnetic noise that is propagated and emitted from a noise source to a drive shaft.   The said shielding member contains the drive shaft shielding material provided so that the said drive shaft may be covered, The shielding member of Claim 1 characterized by the above-mentioned. The shielding member according to claim 2,
Between the noise source and the drive shaft, at least a cable and a motor are provided,
A cable shielding material provided to cover the cable in order to shield electromagnetic noise propagated from the noise source to the cable and radiated;
A motor shielding material provided to cover the motor in order to shield electromagnetic noise propagated from the noise source to the motor and radiated;
The shielding member characterized by further including. The shielding member according to claim 3,
The shielding member, wherein the drive shaft shielding material, the cable shielding material, and the motor shielding material are integrally formed. In the shielding member according to any one of claims 1 to 4,
The noise generating source includes an inverter.   A moving body comprising the shielding member according to claim 1. The mobile body according to claim 6,
The noise generation source is fixed to the moving body frame or the vicinity thereof,
A moving body comprising a conductive medium suspended from the moving body frame and attached to the drive shaft. The mobile body according to claim 7,
The conductive medium has an annular portion;
A moving body comprising the drive shaft inserted through the annular portion.   The mobile body according to claim 5, wherein the mobile body is an electric vehicle or a hybrid vehicle.

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