JPH07227007A - Electromagnetic power feeding device for electric motorcar - Google Patents

Abstract

PURPOSE:To provide such an electromagnetic power feeding device for electric motorcar that a feeding coil on the ground can be electromagnetically coupled with a receiving coil on an electric motorcar in an excellent state without driving the motorcar skillfully. CONSTITUTION:A feeding coil 5 incorporated in a wheel chock 3 is energized by an electric motorcar 6 and changes its attitude in a horizontal plane when an electric motorcar 6 comes into contact with the chock 3 and, when the motorcar 6 is stopped in such a state, the coil 5 assumes a fixed attitude against the motorcar 6. Therefore, when the receiving coil 8 of the motorcar 6 and feeding coil 5 of the chock 3 are arranged so that they can have an excellent electromagnetic conversion efficiency when the motorcar 6 is in contact with the chock 3, the chock 3 and coil 5 change their attitudes in accordance with the moving direction of the motorcar 6 after the motorcar 6 comes into contact with the shock 3 and the power transmitting efficiency between the coils 5 and 8 by electromagnetic induction is improved even when the moving direction of the motorcar 6 is deviated from an ideal direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic power feeder for an electric vehicle.

[0002]

2. Description of the Related Art Conventionally, in order to charge a battery of an electric vehicle, it has been proposed to electromagnetically couple a power feeding coil on the ground side (power feeding station) and a power receiving coil mounted on the electric vehicle to feed power. Japanese Patent Laid-Open No. 63-87136 discloses
A secondary coil (power receiving coil) is installed on the bottom of the body of a battery-powered electric vehicle, etc., and a primary coil (power feeding coil) is installed on a wheel chock on the ground (charging station) side. It discloses that a tire of an electric vehicle is brought into contact with a block-shaped wheel stopper so that both coils are aligned with each other, and an electromagnetic induction effect is used to feed power from a power feeding coil to a power receiving coil to charge a vehicle battery. .

[0003]

In the electromagnetic power feeder for an electric vehicle disclosed in the above publication, the position alignment between the power receiving coil and the power feeding coil is very important for improving the power transmission efficiency.
Unless the electric vehicle is advanced (or retracted) with respect to the power feeding coil at a predetermined advance / retreat angle, the overlapping state of both coils deteriorates,
There is a problem that the power transmission efficiency is reduced.

This alignment problem is the same when the power feeding coil or the power receiving coil is wound around the magnetic core. That is, when the power feeding coil is wound around the magnetic core and the power receiving coil is not wound around the magnetic core, the alignment between the magnetic core and the power receiving coil is important, and the power receiving coil is wound around the magnetic core. If the power feeding coil is not wound around the magnetic core, the alignment between the magnetic core and the power feeding coil becomes important. If both coils are wound around the magnetic core, the magnetic cores are not aligned with each other. Alignment becomes important.

The present invention has been made in view of the above problems, and an electromagnetic power supply for an electric vehicle in which the power supply unit on the ground side can be favorably electromagnetically coupled to the power receiving unit of the electric car without requiring skilled operation of the electric car. The purpose is to provide a device.

[0006]

SUMMARY OF THE INVENTION An electromagnetic power supply device for an electric vehicle according to the present invention is provided with a fixed portion fixed to the ground side and a fixed portion that can be changed in posture in a horizontal plane. A movable body that changes its posture by being biased and comes into contact with the electric vehicle in a fixed posture, a power feeding unit that includes a power feeding coil and that is disposed on the movable body, and a power receiving unit that includes a power receiving coil and that is disposed in the electric vehicle. The power feeding unit and the power receiving unit are electromagnetically coupled with the best electromagnetic conversion efficiency in a state where a predetermined contact portion of the movable portion is in contact with a predetermined contact portion of the electric vehicle. It has a feature.

The power feeding unit or the power receiving unit may have a magnetic core. The power feeding unit may be integrated with the movable body or may be coupled to the movable body so as to be movable relative to the movable body. However, even in this case, the posture of the power feeding unit in the horizontal plane needs to be changed in association with the posture change of the movable body in the horizontal plane. Similarly, the power receiving unit may be integrated with the electric vehicle or may be coupled to the electric vehicle so as to be movable relative to the electric vehicle. However, even in this case, the posture of the power receiving unit in the horizontal plane needs to change in association with the posture change in the horizontal plane of the electric vehicle.

In a preferred first aspect, the power feeding section has a magnetic core around which the power feeding coil is wound. In a preferred second aspect, the power receiving unit has a magnetic core around which the power receiving coil is wound. In a preferred third aspect, the movable body is horizontally rotatably supported by the fixed portion.

In a preferred fourth aspect, the movable body is a wheel stopper capable of abutting on either a pair of front wheels or a pair of rear wheels of the electric vehicle. In a preferred fifth aspect, the movable body has an elastic portion that absorbs the impact energy of the electric vehicle.

[0010]

According to the present invention, the power feeding portion built in the movable body is urged by the electric vehicle contacting the movable body to change its posture in the horizontal plane, and when the electric vehicle is stopped in this state. The power supply unit takes a certain posture with respect to the electric vehicle. Therefore, in advance, when the electric vehicle and the movable body are in contact with each other, the electric power receiving section on the electric vehicle side and the power feeding section on the movable body (ground) side are arranged so as to have good electromagnetic conversion efficiency (power transmission efficiency). In other words, even if the forward / backward direction of the electric vehicle deviates from the predetermined reference direction with respect to the movable body, after the contact between the two, the movable body and the power feeding unit change their postures in accordance with the traveling direction of the electric vehicle, and the electromagnetic induction action is performed. Transmission efficiency is improved.

In the first or second aspect, since the power feeding section or the power receiving section has a magnetic core, the degree of electromagnetic coupling (electromagnetic conversion efficiency), that is, power transmission efficiency is improved. In the third aspect,
The power receiving unit has a magnetic core around which the power receiving coil is wound. In the fourth aspect, since the movable body is only pivotally supported, the structure of the movable body is robust and simple, and the posture of the movable body surely changes following the change in the traveling direction of the electric vehicle.

In the fifth aspect, it is easy to position the power feeding portion and the power receiving portion regardless of the change of the shape of the electric vehicle, and the contact does not damage the electric vehicle. Sixth
In this aspect, it is possible to reduce impact shock on the movable body side and improve durability.

[0013]

【Example】

(Embodiment 1) An embodiment of an electromagnetic power supply device for an electric vehicle of the present invention will be described with reference to the drawings. 1 is a side view of the electromagnetic power supply device for an electric vehicle, FIG. 2 is an enlarged front view of a wheel stopper 3, and FIG.
FIG. 6 is a plan view of the wheel stopper 3.

A base (fixing portion in the present invention) 1 is embedded in the floor of the concrete 100, and a rotation shaft 2 erected on the base 1 has a non-magnetic thick plate elongated stopper. A (movable body in the present invention) 3 is supported so as to be horizontally rotatable. That is, the rotating shaft 2 is rotatably fitted in a shaft hole provided in the center portion of the wheel stopper 3 in the left-right direction. Also,
A power feeding coil (power feeding portion in the present invention) 5 is provided in the center portion of the wheel stopper 3 in the left-right direction, behind the shaft hole and near the upper surface of the wheel stopper 3. Further, the front end surface of the wheel stopper 3 is a slope 30, and the slope 30 comes into contact with a pair of rear wheels 60 of the electric vehicle 6 (the contact portion of the electric vehicle in the present invention) to prevent the electric vehicle 6 from moving backward. It is an abutting part that stops.

On the other hand, on the bottom surface of the rear trunk of the electric vehicle 6, a power receiving coil (power receiving section in the present invention) 8 is arranged at the center of the electric vehicle 6 in the left-right direction. The distance between the rear wheel 60 of the electric vehicle 6 and the power receiving coil 8 can be vertically overlapped with the power feeding coil 5 with a predetermined gap in a state where the rear wheel 60 is in contact with the slope 30 of the wheel stopper 3. It is designed with various dimensions. The axes of both coils 5 and 8 are vertical.

Further, a pair of coil springs (not shown) are wound around the rotating shaft 2 in opposite windings, the base ends of both coil springs are locked to the base 1, and both coil springs (torsion springs) are wound. The urging end of () is locked to the wheel stopper 3. And
At the original position where the longitudinal direction of the wheel stopper 3 is at right angles to the reference backward movement direction of the electric vehicle 6, both coil springs do not urge the wheel stopper 3 and, as a result, when the wheel stopper 3 rotates, these pair of The coil spring urges the wheel stopper 3 to return the wheel stopper 3 to the original position, and after the electric vehicle 6 is detached, the wheel stopper 3 is urged by these coil springs and can return to the original position. .

Next, the positioning operation of both coils 5 and 8 will be described. First, the electric vehicle 6 is driven by operating the electric vehicle 6.
The electric vehicle 6 is moved backward so that the center in the left-right direction coincides with the rotation axis 2 as much as possible. Then, the pair of rear wheels 60 come into contact with the slope 30 of the wheel stopper 3 to stop the electric vehicle 6. When the backward direction of the electric vehicle 6 is deviated from the reference backward direction of the electric vehicle 6, one of the pair of rear wheels 60 of the electric vehicle 6 first comes into contact with the slope 30 of the wheel stopper 3 (see FIG. 4). When the rear wheel 60 on the contact side rotates the wheel stopper 3 in response to the backward movement of the electric vehicle 6, and then both of the pair of rear wheels 60 contact the slope 30 of the wheel stopper 3, the electric vehicle 6 moves backward. Is stopped (see FIG. 5).

By the rotation of the wheel stopper 3, the power feeding coil 5 in the wheel stopper 3 vertically overlaps with the power feeding coil 8 of the electric vehicle 6, and as a result, the power transmission efficiency between the coils 5 and 8 is improved. As shown in FIG. 3, the power feeding coil 5 and the power receiving coil 8 have a shape that is longer in the left-right direction than in the front-rear direction of the electric vehicle 6, so that even if the both coils 5 and 8 are slightly displaced in the left-right direction. The decrease in power transmission efficiency is suppressed.

In this embodiment, since the power feeding coil 5 and the power receiving coil 8 are not wound around the magnetic core, a high frequency current is passed through the power feeding coil 5 to improve power transmission efficiency.
As is conventional, the secondary current induced in the power receiving coil 8 is rectified by a rectifier circuit (not shown) and supplied to the battery (not shown) of the electric vehicle 6. (Embodiment 2) Another embodiment will be described with reference to FIG.
(A) is a vertical sectional view of a main part, and (b) is a plan view thereof.

In this embodiment, the power feeding portion is constituted by the power feeding coil 5 wound around the magnetic core 4, and the power receiving portion is constituted by the power receiving coil 8 wound around the magnetic core 7. To explain further,
A magnetic core 4 made of ferrite is embedded in an upper portion of the wheel stopper 3 made of resin. The magnetic core 4 has a long plate shape with both ends bent, and has a core portion 40 at the center. Both ends of the magnetic core 4 are plate-shaped magnetic pole portions 41 exposed on the upper surface 32 of the wheel stopper 3, and a central portion 42 of the magnetic core 4 is embedded inside the wheel stopper 3. Further, a core portion 40 is erected from the upper surface of the central portion of the magnetic core 4, and the upper end portion of the core portion 40 is exposed at the upper surface 32 of the wheel stopper 3 and is a plate-shaped magnetic pole portion 4.
It is 4. The feeding coil 5 is wound around the core 40.

Since the magnetic core 7 and the power receiving coil 8 constituting the power receiving unit have the same structure as the power feeding unit described above, the description thereof will be omitted. However, the upper surface of the central portion of the magnetic core 7 is the rod 71.
The rod 71 is fixed to the end of the electric vehicle 6 and can be moved up and down by a cylinder (not shown) built in the rear trunk of the electric vehicle 6. In this embodiment, both magnetic cores 4, 7
Positioning of the magnetic pole surface M of the magnetic pole surface M is important for improving the power transmission efficiency, but the rotational position of the magnetic pole surface M of the magnetic cores 4 and 7 is adjusted by rotating the wheel stopper 3 in the horizontal plane as in the first embodiment. Has become easier. However, the magnetic pole surfaces M of both magnetic cores 4 and 7 depend on the stop position of the electric vehicle 6, and
Although a positional deviation occurs in the longitudinal direction (the left-right direction of the electric vehicle 6), since each magnetic pole surface M is extended to the left and right with a margin, even if some positional deviation occurs, the power transmission efficiency does not decrease.

Further, in this embodiment, the electric vehicle 6 has the wheel stopper 3
Since the cylinder is driven and the magnetic core 7 is moved down after stopping by contacting with, the magnetic resistance of the magnetic circuit during power transmission is small, and extremely high power transmission efficiency can be obtained. Of course, when the charging is completed, the magnetic core 7 moves up to the original position. Instead of lowering the magnetic core 7 toward the magnetic core 4, the cylinder is built in or integrated with the wheel stopper 3, and this cylinder raises the magnetic core 4 at the tip of the rod (not shown) to approach the magnetic core 7. You may let me. (Embodiment 3) Another embodiment will be described with reference to FIG.

A base 1 is embedded in the floor surface of concrete 100, and a non-magnetic thick plate elongated wheel stopper (a movable body in the present invention) is attached to a rotating shaft 2 erected on the base 1. Three
Is rotatably supported horizontally. At the center portion of the wheel stopper 3 in the left-right direction, a power feeding portion 5a similar to that of the second embodiment is disposed behind the shaft hole 30 and near the upper surface of the wheel stopper 3.

Further, in this embodiment, the wheel stopper 3 is formed with a square concave portion 36 having a front end opening, and the square concave portion 36 is slidable with the base portion of the abutting portion 37 abutting against the rear wheel 60 of the electric vehicle 6. It is housed in. Further, a plurality of springs (an elastic portion in the present invention, one is shown) 38 are housed in the rectangular recess 36, and these springs 38 push the contact portion 37 forward, that is, leftward in the figure. . In addition, a groove (not shown) is formed in the rectangular concave portion 36, while a protrusion-shaped stopper that fits into this groove is formed in the contact portion 37, and this stopper is locked at the end of the groove. As a result, the further protrusion of the contact portion 37 is restricted. The front end surface of the abutting portion 37 is the same as in the other embodiments.
The inclined surface 30 contacts the pair of rear wheels 60.

In this way, when the pair of rear wheels 60 of the electric vehicle 6 come into contact with the slope 30, the contact portion 37 first compresses the spring 38 and retracts, whereby the rear wheel 60 and the wheel stopper 3 are separated. It is possible to alleviate the impact shock between the two and to rotate the wheel stopper 3 together with it, so that the wheel stopper 3 and the power feeding portion 5a can be placed in a fixed posture with respect to the electric vehicle 6, and the shock to the rotating shaft 2 is reduced. be able to.

In each of the above-described embodiments, the wheel stopper 3 is rotated by the backward movement of the rear wheel 60, so that the influence of the steering of the front wheel can be ignored. Of course, the front wheels advance 3
Can also be rotated. (Modification) In the above embodiment, the wheel stopper 3 constitutes the movable body referred to in the present invention, but it is also possible to employ a movable body which is rotated by the vehicle body of the electric vehicle 6 (particularly a bumper).

(Modification) In the above embodiment, the movable body composed of the wheel stopper 3 rotates about the rotation shaft 2, but
It is also possible to connect the movable body to the fixed body through an elastic member so as to be elastically deformable in the horizontal plane. Even in this case, the movable body can take a fixed posture with respect to the electric vehicle 6 by the biasing of the electric vehicle 6 moving forward and backward. it can. (Embodiment 4) Another embodiment will be described with reference to FIG.

A base 10 is provided on the floor of the concrete 100.
1 is embedded, and a pair of elongated holes 102 are formed through the front-rear vertical end faces of the base 101 in the front-rear direction.
The long hole 102 has a cross-sectional shape that is long in the horizontal direction. A guide bar 103 is fitted in the elongated hole 102, and a stopper plate 104 is fixed to the rear end of the guide bar 103.

The guide bar 103 has a coil spring 1
05 is wound, and a wheel stopper 106 is fixed to the front end portion of the guide bar 103. Wheels 107 (only one is shown) are rotatably provided at both left and right ends of the wheel stopper 106, and the wheel stopper 106 allows the wheel stopper 106 to move forward and backward. Further, since the elongated hole 102 has a cross section that is long in the horizontal direction, the wheel stopper 106 can rotate within a certain angle range within the horizontal plane. The base end of the coil spring 105 is locked to the base 101,
The biasing end of the coil spring 105 biases the wheel stopper 106 forward. Reference numeral 108 denotes a plate on which the base end of the coil spring 105 is seated.

Further, similarly to the third embodiment, the power feeding portion 5a is disposed above the wheel stopper 106. In this way, the elastic movement of the wheel stopper 106 can reduce the shock caused by the collision between the wheel stopper 106 and the tire, and
The rotation of the wheel stopper 106 also improves the power feeding efficiency by aligning the power feeding portion 5a.

[Brief description of drawings]

FIG. 1 is a side view of an electromagnetic power feeder for an electric vehicle according to a first embodiment.

2 is a front view of a wheel stopper 3 of the apparatus of FIG.

FIG. 3 is a plan view of the wheel stopper 3 of FIG.

FIG. 4 is a schematic plan view showing a case where only one of the rear wheels 60 contacts the wheel stopper 3.

FIG. 5 is a schematic plan view showing a case where both rear wheels 60 contact the wheel stopper 3.

FIG. 6A is a cross-sectional side view showing an electromagnetic power feeder for an electric vehicle according to a second embodiment, and FIG. 6B is a plan view of a magnetic core 7.

FIG. 7 is a sectional side view showing a wheel stopper 3 according to a third embodiment.

8A is a sectional side view showing a wheel stopper structure of Example 4, and FIG. 8B is a plan view thereof.

[Explanation of symbols]

1 is a base (fixed part), 2 is a rotating shaft, 3 is a wheel stopper (movable body), 4 is a magnetic core, 5 is a power feeding coil, 6 is an electric vehicle, 7
Is a magnetic core, and 8 is a power receiving coil.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H02J 17/00 B

Claims (6)

[Claims] 1. A fixed part fixed to the ground side and a fixed part supported by the fixed part so that the position can be changed in a horizontal plane, and the position is changed by urging the electric vehicle to maintain a constant attitude with respect to the electric vehicle. And a power supply unit including a power supply coil and disposed in the movable body, and a power reception unit disposed in the electric vehicle including a power reception coil, wherein the power supply unit and the power reception unit are An electromagnetic power supply device for an electric vehicle, wherein electromagnetic coupling is performed with the best electromagnetic conversion efficiency in a state where a predetermined contact portion of the movable portion is in contact with the predetermined contact portion of the electric vehicle. 2. The electromagnetic power feeding device for an electric vehicle according to claim 1, wherein the power feeding portion has a magnetic core around which the power feeding coil is wound. 3. The electromagnetic power feeder for an electric vehicle according to claim 1, wherein the power receiving unit has a magnetic core around which the power receiving coil is wound. 4. The electromagnetic power feeder for an electric vehicle according to claim 1, wherein the movable body is supported by the fixed portion so as to be horizontally rotatable. 5. The electromagnetic power supply device for an electric vehicle according to claim 1, wherein the movable body is a wheel stopper capable of abutting on either a pair of front wheels or a pair of rear wheels of the electric vehicle. 6. The electromagnetic power supply device for an electric vehicle according to claim 1, wherein the movable body has an elastic portion that absorbs impact energy of the electric vehicle.