Vehicle-mounting structure for contactless power reception device

A power reception coil is a circular coil having a hollow portion formed in a center portion of the power reception coil in a radial direction. The power reception coil, a resonant capacitor, and a magnetic member are arranged in a power reception coil unit forming a contactless power reception device. The power reception coil unit is attached to a member element serving as a frame member of a vehicle body. A hollow portion corresponding region which is a portion of the power reception coil unit corresponding to the hollow portion of the power reception coil is in contact with the member element.

TECHNICAL FIELD

The present invention relates to a vehicle-mounting structure for a contactless power reception device.

BACKGROUND ART

A contactless power feeding apparatus including a contactless power transmission device installed on a road surface and a contactless power reception device mounted in a vehicle has been conventionally publicly known (see, for example, Patent Literature 1). The contactless power reception device includes a power reception coil unit.

In Patent Literature 1, the power reception coil unit is attached to both of paired left and right base portions across a tunnel portion formed in a floor panel of the vehicle. Specifically, the tunnel portion and the base portions extend in a vehicle front-rear direction and left and right end portions of the power reception coil unit are fastened to the paired left and right base portions with bolts.

CITATION LIST

Patent Literature

Patent Literature 1: Japanese Patent Application Publication No. 2016-112899

SUMMARY OF INVENTION

However, the power reception coil unit includes a power reception coil and a center portion of the power reception, coil in the radial direction is formed to be a hollow portion. Accordingly, among portions of the power reception coil unit, a portion including the center portion of the power reception coil in the radial direction has lower stiffness than the end portions. Thus, there is a risk that, in the power reception coil unit supported at the left and right end portions, the center portion in the left-right direction vibrates in an up-down direction and generate abnormal noise in traveling of the vehicle.

In view of this, the present invention provides a vehicle-mounting structure for a contactless power reception device which can maintain high holding stiffness in the case where a power reception coil unit is mounted in a vehicle.

In a vehicle-mounting structure for a contactless power reception device according to the present invention, a power reception coil unit is mounted on a member element serving as a frame member of a vehicle body. The power reception coil unit includes a power reception coil. The power reception coil is a circular coil in which a hollow portion is formed in a center portion in a radial direction. A hollow portion corresponding region which is a portion of the power reception coil unit corresponding to the hollow portion of the power reception coil is in contact with the member element.

ADVANTAGEOUS EFFECTS OF INVENTION

In the present invention, the stiffness at which the power reception coil unit is held is improved and vibration and the like of the power reception coil unit in traveling of the vehicle are reduced.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention are described below in detail with reference to the drawings.

First Embodiment

A contactless power feeding apparatus1illustrated inFIG. 1includes a contactless power transmission device3installed in a parking space and a contactless power reception device7mounted in a vehicle5. For example, an electric car, a hybrid car, and the like are applicable as the vehicle5.

The contactless power transmission device3includes: a power transmission coil unit11installed on a road surface9of the parking space and including a power transmission coil; a power supply device13; and a wire15connecting the power transmission coil unit11and the power supply device13to each other. The power transmission coil is formed mainly of a primary coil made of an electrically-conductive wire.

The contactless power reception device7includes a power reception coil unit17, a rectifier19, a relay box21, a battery23, an inverter25, a motor27, and a reducer29. Note that the power reception coil unit17includes a power reception coil83and a detailed structure of the power reception coil unit17is described later.

The rectifier19is connected to a junction box31of the power reception coil unit17via a first harness33. The rectifier19is formed of a rectifier circuit configured to rectify AC power received by the power reception coil83to a direct current. The first harness33is loosely routed with an extra length in a normal state (state of no abnormality such as collision).

The relay box21includes a relay switch. A main circuit system including the battery23can be isolated from the power reception coil and the rectifier19which form a charge circuit part by turning off the relay switch.

The battery23is formed by connecting multiple secondary cells to one another. The battery23is a power source of the vehicle5. The battery23and the relay box21are connected to each other via a second harness35. The second harness35is loosely routed with an extra length in a normal state (state of no abnormality such as collision).

The inverter25is a control circuit such as a PWM control circuit including a switching element such as an IGBT. The inverter25converts DC power outputted from the battery23to AC power based on a switching control signal and supplies the AC power to the motor27. The inverter25and the battery23are connected to each other via a third harness37. The third harness37is loosely routed with an extra length in a normal state (state of no abnormality such as collision).

The motor27is formed of, for example, a three-phase AC electric motor. The motor27serves as a drive source for driving the vehicle5. The reducer29adjusts the revolution speed of the motor27to an appropriate value. Note that, in the vehicle5ofFIG. 1, a front portion of the power reception coil unit17is arranged to overlap a front wheel39in a side view and the power reception coil unit17is arranged inside the front wheel39in a vehicle width direction.

As illustrated inFIG. 2, paired left and right side sills41extending in a front-rear direction are provided on sides of the battery23. Paired left and right hood ridge supports43extending in the front-rear direction are provided in front of the side sills41. A rear end45aof a dash panel45is arranged adjacent to a front end23aof the battery23. Note that, as illustrated inFIGS. 1 and 2, a rear portion of the dash panel45is laid below a front portion of a floor panel47and is joined thereto. The dash panel45extends in an up-down direction and partitions a front compartment1F and a vehicle cabin1R from each other.

Moreover, as illustrated inFIG. 2, paired left and right front side members49extend in the front-rear direction. Rear ends49aof the front side members49are arranged adjacent to the front end23aof the battery23and front ends49bof the front side members49are arranged at a front end of the vehicle. Paired left and right front cross members51are arranged at the front end of the vehicle. Connection members53extend in a front-rear direction. Front portions of the left and right connection members53are connected to each other by a front member54extending in the vehicle width direction. Rear portions53aof the connection members53are joined to front leg portions57(seeFIG. 4) of a suspension member55. Lower arms59extending in the vehicle width direction are connected to side portions of the suspension member55and the hood ridge supports43.

As illustrated inFIGS. 3 and 4, the suspension member55is a member element serving as a frame member of a vehicle body and has high stiffness. The suspension member55is connected to the vehicle body in a normal state and is configured to be detachable from the vehicle body when predefined impact load is inputted into the suspension member55. Specific description is given below.

As illustrated inFIG. 2, the suspension member55is formed integrally of the paired left and right front leg portions57extending forward, a front connection portion61connecting base portions of the paired left and right front leg portions57to each other in the vehicle width direction, main body side portions63extending rearward from rear ends of the front leg portions57, and a rear connection portion65connecting rear ends of the main body side portions63to each other in the vehicle width direction. Moreover, rear leg portions67extend rearward from the rear ends of the main body side portions63and rearward extending portions69extend rearward from the rear ends of the main body side portions63, inside the rear leg portions67in the vehicle width direction. The rear leg portions67are fastened to the front side members49via not-illustrated brackets. Moreover, the rearward extending portions69are formed in a square tube shape and bolt holes are formed in rear end portions. Weld nuts71are joined to the bolt holes. A rear flange73is formed in a rear portion of the front connection portion61to extend in the vehicle width direction and bolt holes75are formed in the rear flange73.

As illustrated inFIGS. 3 to 5andFIGS. 6A to 6E, the power reception coil unit17includes a cover81, the power reception coil83, a power transmission coil side magnetic member85, a vehicle side magnetic member87, a resonant capacitor89, and a base plate91.

The cover81is formed integrally of a flat surface portion93formed to have a rectangular shape in a plan view and a flange portion95bent and extending upward from a peripheral edge of the flat surface portion93. The cover81is made of a non-magnetic material (for example, resin) which does not hinder electromagnetic induction.

The power reception coil83is a circular coil in which an electrically-conductive wire is wound in an annular shape. The power reception coil83is formed mainly of a secondary coil made of the electrically-conductive wire. A hollow portion97having a rectangular shape in the plan view is formed in a center portion of the power reception coil83in a radial direction thereof.

The power transmission coil side magnetic member85(magnetic member) is a magnetic material formed into a flat plate with a rectangular shape in the plan view. The power transmission coil side magnetic member85is housed inside the hollow portion97of the power reception coil83. Moreover, the thickness of the power transmission coil side magnetic member85is set to be equivalent to the thickness of the power reception coil83.

The vehicle side magnetic member87(magnetic member) is arranged on top of the power transmission coil side magnetic member85and the power reception coil83. The vehicle side magnetic member87is a magnetic material formed into a flat plate with a rectangular shape in the plan view. The size of the vehicle side magnetic member87in a plane direction is set to be substantially the same as the flat surface portion93of the cover81. The vehicle side magnetic member87is formed integrally of a front portion99arranged on the vehicle front side, a center portion101arranged behind the front portion99, and a rear portion103arranged behind the center portion101. A bottom surface of the vehicle side magnetic member87is flat while the height of an upper surface of the vehicle side magnetic member87varies depending on the portions. Specifically, the height Hc of the center portion101is set to be the lowest, the height Hf of the front portion99is set to be higher than the height Hc of the center portion101, and the height Hr of the rear portion103is set to be higher than the height Hf of the front portion99. In other words, the magnitude relationship of He<Hf<Hr is set. For example, ferrite or the like can be preferably used for the power transmission coil side magnetic member85and the vehicle side magnetic member87.

Note that “power transmission coil side” in the power transmission coil side magnetic member85is the side closer to the “power transmission coil” than to the “vehicle5” and is the lower side (road surface side) in the embodiment. Moreover, “vehicle side” in the vehicle side magnetic member87is the side closer to the “vehicle5” than to the “power transmission coil” and is the upper side in the embodiment. As described above, the magnetic member includes the power transmission coil side magnetic member85and the vehicle side magnetic member87.

The resonant capacitor89is connected to the power reception coil83in series and form a resonance circuit together with the power reception coil83. The resonant capacitor89is an electronic part. The resonant capacitor89is placed on top of the rear portion of the vehicle side magnetic member87.

The base plate91is formed integrally of a forward portion105, a center portion107, and a rearward portion109, like the vehicle side magnetic member87. The base plate91is made of a non-magnetic material (for example, aluminum) which does not hinder electromagnetic induction. The height of the center portion107is set to be the lowest, the height of the forward portion105is set to be higher than the height of the center portion107, and the height of the rearward portion109is set to be higher than the height of the forward portion105. The junction box31is arranged on an upper surface of the rearward portion109.

A connector portion111is formed on a front surface of the junction box31. The first harness33is connected to the connector portion111. Moreover, a rectangular hollow portion corresponding region113illustrated by two-dot chain lines is set to extend over the center portion107and the rearward portion109. This hollow portion corresponding region113is a portion facing the hollow portion97of the power reception coil83. Support pieces115are provided to protrude from left and right sides of the rearward portion109and from a front side of the forward portion105. Bolt holes117are formed in the respective support pieces115.

With such a configuration, the contactless power feeding apparatus contactlessly supplies power from the power transmission coil to the power reception coil83by way of electromagnetic induction (magnetic coupling) between the power transmission coil and the power reception coil83.

Moreover, the power reception coil83, the resonant capacitor89, the power transmission coil side magnetic member85, and the vehicle side magnetic member87(magnetic member) are arranged in the power reception coil unit17.

Next, a procedure of attaching the power reception coil unit17to the suspension member55is described.

As illustrated inFIG. 4, first, in a rear end portion of the power reception coil unit17, the support pieces115in the rear portion of the power reception coil unit17are fastened to the rearward extending portions69of the suspension member55. Specifically, bolts BL are inserted into the bolt holes117of the support pieces in the rear portion of the power reception coil unit17from below and are fastened to the weld nuts71joined to the rearward extending portions69of the suspension member55.

Next, in the front end portion of the power reception coil unit17, the support pieces115in the front portion of the power reception coil unit17are fastened to the rear flange73of the suspension member55. Specifically, the bolts BL are inserted into the bolt holes117of the support pieces115in the front portion of the power reception coil unit17from below and are fastened to the bolt holes75formed in the rear flange73of the suspension member55.

As described above, the power reception coil unit17is attached to the suspension member55which is the member element serving as the frame member of the vehicle body.

As illustrated inFIGS. 6D and 6E, the rear connection portion65in the suspension member55is formed to have a closed cross-section structure with high stiffness. Specifically, the entire suspension member55including the rear connection portion65is formed by joining a lower member121arranged on the lower side and an upper member123arranged on the upper side. In the rear connection portion65, front and rear end portions of the lower member121and front and rear end portions of the upper member123are joined to each other and a hollow portion125is thereby formed inside these members. A bottom surface121aof the lower member121is in contact with the hollow portion corresponding region113set in the upper surface of the base plate91in the power reception coil unit17. In the embodiment, specifically, the bottom surface121aof the lower member121is in contact with the upper surface of the center portion107of the base plate91. Moreover, a rear end of the lower member121is arranged close to a vertical wall127formed at a boundary between the center portion107and the rearward portion109of the base plate91.

Moreover, as illustrated inFIGS. 6D and 6E, the resonant capacitor89is housed inside the rearward portion109of the base plate91. The height at which the resonant capacitor89is arranged is equivalent to the height at which the rear connection portion65in the suspension member55is arranged. As described above, the electronic part including the resonant capacitor89is arranged behind and adjacent to the rear connection portion65(member element).

Operations and effects of the first embodiment are described below.

(1) The contactless power feeding apparatus1according to the first embodiment contactlessly supplies power to the vehicle5by way of magnetic coupling between the power transmission coil installed in the parking space and the power reception coil83mounted in the lower portion of the vehicle body of the vehicle5. The power reception coil83is a circular coil in which the hollow portion97is formed in the center portion in the radial direction. The power reception coil83, the resonant capacitor89, and the set of the vehicle side magnetic member87and the power transmission coil side magnetic member85(magnetic member) are arranged in the power reception coil unit17. The power reception coil unit17is attached to the suspension member55which is the member element serving as the frame member of the vehicle body. The hollow portion corresponding region113which is the portion of the power reception coil unit17corresponding to the hollow portion97of the power reception coil83is in contact with the suspension member55(member element).

The power reception coil unit17includes the power reception coil83and the hollow portion97is formed in the center portion of the power reception coil83in the radial direction. Accordingly, when the end portions of the power reception coil unit17are fixed to the vehicle body, the stiffness of the portion of the power reception coil unit17corresponding to the hollow portion97of the power reception coil83decreases. The portion of the power reception coil unit17corresponding to the hollow portion97of the power reception coil83is thus in contact with at least part of the suspension member55(member element) and the holding stiffness in the case where the power reception coil unit17is held on the vehicle body is thereby improved. Vibration and the like of the power reception coil unit17in traveling of the vehicle are thereby reduced.

(2) The suspension member55(member element) is connected to the vehicle body in the normal state and is configured to be detachable from the vehicle body when predefined impact load is inputted into the suspension member55. Moreover, the power reception coil unit17is attached to the suspension member55.

Accordingly, when the predefined impact load is inputted into the suspension member55in a rearward direction, the power reception coil unit17and the suspension member55move rearward integrally. Specifically, the power reception coil unit17and the suspension member55move rearward integrally without the relative distance between the power reception coil unit17and the suspension member55changing. Accordingly, the suspension member55protects the power reception coil unit17and deformation, damage, and the like of the power reception coil unit17are suppressed.

(3) The magnetic member includes the vehicle side magnetic member87arranged on the vehicle side and the power transmission coil side magnetic member85arranged on the power transmission coil side. The power transmission coil side magnetic member85is arranged in the hollow portion97of the power reception coil83.

The power transmission coil side magnetic member85is arranged on the power transmission coil side of the vehicle side magnetic member87. Specifically, since the power transmission coil side magnetic member85is arranged below the vehicle side magnetic member87, the power transmission coil side magnetic member85is arranged close to the power transmission coil. This configuration has such an effect that the power transmission coil side magnetic member85can more easily receive the magnetic flux transmitted from the power transmission coil.

Moreover, the power transmission coil side magnetic member85is arranged in the hollow portion97of the power reception coil83. Housing the power transmission coil side magnetic member85in the hollow portion97of the power reception coil83which would otherwise be a dead space can improve the space efficiency in arranging the parts in the power reception coil unit17.

(4) The electronic part including the resonant capacitor89is arranged behind and adjacent to the suspension member55(member element).

The suspension member55is the member element serving as the frame member of the vehicle body. Accordingly, the suspension member55protects the electronic part including the resonant capacitor89and the damage and the like of the electric parts can be suppressed.

(5) The rectifier19is connected to the junction box31via the first harness33. The first harness33is loosely routed with an extra length in the normal state (state of no abnormality such as collision).

This configuration has such an effect that, when the power reception coil unit17moves in vehicle collision, tension is less likely to act on the first harness33and the first harness33is thus less likely to break.

Second Embodiment

Next, the second embodiment is described. Portions with the same configurations as those in the aforementioned first embodiment are denoted by the same reference numerals and description thereof is omitted.

In the second embodiment, a power reception coil unit217is fastened to a center portion, in the vehicle width direction, of the rear connection portion65of the suspension member55with the bolts BL.

As illustrated inFIG. 7, in the power reception coil unit217according to the second embodiment, a protruding portion201protruding upward is formed in a center portion of a flat surface portion293of a cover281. This protruding portion201is formed integrally of a cylinder surface203protruding upward and circumferentially extending in a circle and an upper surface205closing an upper opening of the cylinder surface203. A bolt hole207is formed at the center of the upper surface205in the radial direction. A circular hole209with a size equivalent to the outer diameter of the protruding portion201is formed in a power transmission coil side magnetic member285. Bolt holes211,213are formed also in a vehicle side magnetic member287and a base plate291, respectively.

Moreover, as illustrated inFIGS. 8A, 8B, and 9, a bolt hole and a weld nut215are provided in a center portion, in the vehicle width direction, of the lower member121in the rear connection portion65in the suspension member55.

A procedure of fastening the power reception coil unit217to the rear connection portion65with the bolt is described below.

First, the bolt BL is inserted from below the power reception coil unit217and a distal end portion of the bolt BL is made to protrude from the base plate291. Next, the distal end portion of the bolt BL is inserted into the bolt hole in the lower member121of the rear connection portion65and fastened to the weld nut215.

Operations and effects of the second embodiment are described below.

(1) The power reception coil unit217is fastened to the center portion, in the vehicle width direction, of the rear connection portion65of the suspension member55with the bolt BL.

This configuration has such an effect that the stiffness at which the power reception coil unit217is held by the suspension member55is increased from that in the first embodiment and the vibration and the like of the power reception coil unit17in the traveling of the vehicle are further reduced.

Although the contents of the present invention have been described above according to the embodiments, the present invention is not limited to these descriptions and it is apparent to those skilled in the art that various modifications and improvements can be made.

For example, although the structure is such that the power transmission coil side magnetic member85and the vehicle side magnetic member87forming the magnetic member are separate bodies, the power transmission coil side magnetic member85and the vehicle side magnetic member87may be integrally formed.

REFERENCE SIGNS LIST