JPH06165302A - Electromagnetic power supply for motor operated vehicle - Google Patents

Abstract

PURPOSE:To alleviate the weight of a primary core by forming the core in an upright columar state, and incorporating a square section surrounding the core in a secondary core. CONSTITUTION:A movable primary core 1 wound with a primary coil (transmission side) 2 is formed in an upright columnar state, and a secondary core 3 wound with a secondary coil (power reception side) 4 has a square section surrounding the core 1. The core 1 is engaged from a window W of the core 3 while sliding it on a guide surface 61 by grasping a hand grip 59. When the core 1 is engaged as it is, a magnetic flux output/input end face 15 of upper side of the core 1 is finally engaged with an end face of a central column 39 of the core 3 to be connected, and completely aligned at the position. Thus, the core 1 can be formed of only part of a central leg of a three-leg type closed magnetic path core. Thus, the weight of the core 1 can be reduced as compared with that of the core 3.

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.

[0002]

2. Description of the Related Art USP 4,347,472, 449689
6, JP-A-63-73837 discloses that a secondary coil-wound secondary core is fixed to the bottom or front of a battery-driven electric vehicle, and a primary coil-wound primary core is fixed to the ground side. , It is disclosed that both cores are aligned with each other by a driving operation of an electric vehicle to form a gapped magnetic circuit and power is supplied.

[0003]

However, in the proposal of the above publication, it is extremely difficult to align both cores,
Power conversion efficiency due to rough alignment (secondary active power /
There was a problem that the decrease in primary active power) had to be tolerated. Further, if it is intended to improve the power conversion efficiency,
There is no choice but to increase the size of both cores, but increasing the size of the cores cannot achieve a significant improvement in power conversion efficiency. Further, in the prior art, the position and shape of the secondary core in the vehicle body are regulated in accordance with the shape and position of the ground-side primary core, which is a great constraint on the vehicle design.

In view of the above problems, the present inventors grasped the primary core (station side) wound with the primary coil by a person, aligned the primary core with the secondary core, and fed power in this state to obtain a precise position. We thought that the core could be downsized because the gap could be reduced by matching. However, when grasping the primary core and aligning it with the secondary core in this way, there are the following problems.

First, since the primary coil-wound primary core is still small, it still has a considerable weight. Therefore, grasping and moving or precisely aligning it puts a heavy burden on the wrist. . A first object of the present invention is to provide an electromagnetic power supply device for an electric vehicle capable of significantly reducing the weight of the moving-side primary core as compared with the conventional one.

Next, when such a small primary core or secondary core is used, the areas of the magnetic flux inflow / outflow end faces of both are inevitably small, and in order to reduce the magnetic resistance of the gap part,
It is necessary to improve the bondability between the magnetic flux inflow and outflow end faces to reduce the gap length. However, such a reduction in the gap length requires high accuracy for the alignment work of the primary core, and thus the work becomes difficult.

A second object of the present invention is to shorten the gap length without complicating the positioning work of both cores. Next, in order to use such a small-sized core, a method by increasing the frequency is preferable, and for that purpose, a ferrite core having almost no eddy current loss is preferable. However, since the ferrite core is brittle and vulnerable to impact, the impact at the time of alignment between the primary core and the secondary core becomes a problem.

A third object of the present invention is to provide an electromagnetic power feeder for an electric vehicle which can reduce the impact on the cores when the cores are aligned.

[0009]

An electromagnetic power feeder for an electric vehicle according to the present invention has a movable primary core around which a primary coil is wound, and a magnetic flux input / output end surface that can be joined to the magnetic flux input / output end surface of the primary core. For an electric vehicle including a secondary core that forms a closed magnetic circuit with a gap by joining both magnetic flux inflow and outflow end faces, and a secondary coil wound around the secondary core, and the secondary core is disposed in the vehicle body. In the electromagnetic power feeder, the primary core is formed in an upright column shape, and the secondary core has a square cross section surrounding the primary core. In addition, in this specification, the square cross section includes a structure having a protrusion at a portion in contact with the facing end surface of the upright columnar primary core.

In a preferred embodiment, the magnetic flux is formed close to the secondary core on the vehicle body, and the primary core is fitted so as to be parallel to at least one of the magnetic flux input / output end surfaces of the secondary core. It has a guide surface for guiding to the joining position. In a preferred aspect, the magnetic flux inflow / outflow end surface of the primary core has an inclined surface which is tapered in the fitting direction.

[0011]

In this electromagnetic power supply device for an electric vehicle, the secondary coil wound on the secondary coil (power receiving side) is fixed to the vehicle, and the primary coil wound on the primary coil (power transmitting side) is connected to the secondary core. Align with. The primary core that needs to be moved is formed in an upright column shape, and the secondary core has a square cross section surrounding the primary core. With this configuration, the primary core can be fitted into the central portion of the secondary core to form a tripod type closed magnetic circuit core with little leakage flux. Further, since the primary core can be configured only by the central leg of the tripod type closed magnetic circuit core, the primary core can be significantly reduced in weight as compared with the secondary core.

The tripod type closed magnetic circuit core referred to herein is a central leg portion and end portions on both sides thereof which are magnetically connected to the first base portion to form a central leg portion and end leg portions on both sides thereof. A closed magnetic circuit core having a shape in which the other end of each of the above is magnetically connected to the second base. If a guide surface is provided that guides the insertion of the primary core parallel to at least one of the magnetic flux input / output end surfaces of the secondary core to the joining position of both magnetic flux input / output end surfaces, alignment (primary core insertion)
At times, the two cores are less likely to contact each other, and damage to the cores can be suppressed.

If the magnetic flux inlet / outlet end surface of the primary core is formed into a slanted surface which is tapered in the fitting direction, both magnetic flux inlet / outlet end surfaces are brought into close contact with each other only by inserting the primary core in one direction, which leads to higher accuracy in the positioning work. The gap length can be significantly reduced. In addition, the reduction in size of the core improves the degree of freedom in the position of disposing the secondary core on the vehicle body without lowering the power conversion efficiency (for example, the secondary core can be disposed at the vehicle rear part or the vehicle upper part). After guiding and aligning the primary core to the joining position with the secondary core, the restriction of the guide locking portion prevents the primary core from displacing and lowering the power conversion efficiency.

[0014]

(Embodiment 1) An embodiment of an electromagnetic power supply device of the present invention is shown in FIGS. FIG. 1 is a sectional view taken along the coil shaft center and cut in the primary core fitting direction, FIG. 2 is a sectional view taken along the arrow of FIG. 1 (a sectional view perpendicular to the shaft center), and FIG. FIG.

A primary coil 2 is wound around a primary core 1 formed of a short-axis cylinder, and both end faces (magnetic flux input / output end faces) 15 and 16 of the primary core 1 are magnetic flux input / output end faces 35 of the secondary core 3.
Close to 36. The magnetic flux inlet / outlet end surface 15 is a slant surface which is tapered in the primary core fitting direction. The secondary coil 4 is covered with a support portion 5 made of resin, and the primary core 1, the primary coil 2, and the support portion 5 have a thick disc shape as a whole. Furthermore, a handgrip 5 made of resin that can be grasped
Reference numeral 9 extends from the base side of the support portion 5 in the fitting direction to the opposite fitting direction.

The secondary core 3 is composed of a bottom plate portion 31, an outer wall portion (end leg portion) 32, a top plate portion 33, and central pillar portions 38 and 39.
It has a square cross section that is parallel to the axis and is perpendicular to the direction in which the primary core is inserted. The bottom plate portion 31 and the top plate portion 33 have a semicircular semi-rectangular shape in which the kamaboko is viewed in the longitudinal direction thereof, and extend at a predetermined interval in the direction perpendicular to the coil axis (primary core fitting direction). A central column portion 38 stands upright from the center of the upper surface of the bottom plate portion 31 in the axial direction of the coil, while a central column portion 39 hangs from the central portion of the lower surface of the top plate portion 33 in the axial direction of the coil.
The secondary coil 4 is wound around the central pillar portion 38, and the tip end surface of the central pillar portion 38 is a flat surface extending in a direction perpendicular to the coil axis which can be in close contact with the magnetic flux inlet / outlet end surface 16 of the primary core 1. ing. The central column portion 39 is formed in a short axis, and its tip end surface is an inclined surface that can come into close contact with the magnetic flux inflow / outflow end surface 15 of the primary core 1. The central pillar portions 38, 39 and the primary core 1 form the central leg portion of the tripod type closed magnetic circuit core.

As shown in FIG. 2, the outer wall portion (end leg portion) 32 is a U-shaped wall body whose cross section perpendicular to the coil axis is open in the primary core fitting direction. Both ends of the portion (end leg portion) 32 are formed along the outer periphery of the bottom plate portion 31 and the top plate portion 33, and as a result, the secondary core 3 is an opening into which the primary core 1 is fitted at a right angle to the coil axis. It is a can body having W on the outer circumference and sealed at both ends.

Further, as shown in FIG. 1, the lower half of the inside of the secondary core 3 is filled with a support portion 6 made of resin so as to cover the secondary coil 4, and the upper surface of the support portion 6 (the present invention). The guide surface 61 is a tip surface of the central column portion 38 (actually, a thin silicon resin film is applied to the tip surface of the central column portion 38, but in the present embodiment, illustration and description are omitted). It is on the same plane.

Here, the primary core 1 and the secondary core 3 are made of ferrite cores, and the supporting portions 5 and 6 are made of epoxy resin. Next, the operation of this device will be described. FIG. 3 shows a state where the hand grip 59 is grasped by hand and the primary core 1 is slid on the guide surface while being fitted into the interior of the secondary core 3 through the window W.

When the primary core 1 is inserted into the secondary core 3 as it is, finally, the magnetic flux outgoing / incoming end surface 15 on the upper side of the primary core 1 is inserted into the secondary core 3.
Is fitted and locked to the tip end surface of the central pillar portion 39, and the alignment is completed at that position. Then, when the primary coil is energized, a gapped magnetic circuit is formed between the cores 1 and 3, and an output voltage is induced in the secondary coil 4.

In this way, the upright columnar primary core 1
Can be constructed by only a part of the central leg of the tripod type closed magnetic circuit core, and can be significantly reduced in weight as compared with the secondary core 3. In addition, the primary core 1 is inserted into the upper end surface 6 of the support portion 6.
Since the guide is performed by 1, the cores 1 and 3 rarely come into contact with each other at the time of alignment (fitting of the primary core 1), and damage to the cores 1 and 3 can be prevented.

Furthermore, since the magnetic flux exit / entry end surface 15 of the primary core 1 and the tip end surface of the central column portion 39 of the secondary core 3 that is joined to the magnetic flux exit / end end surface 15 are formed as slopes that taper in the fitting direction, they can be fitted easily, and The tip of the support portion 5 hits the outer wall portion 32, and further fitting is restricted. Further, since the magnetic flux inlet / outlet end surface 15 is a slope, the facing area is wide, and the magnetic resistance can be reduced.

In the above embodiment, the primary side and the secondary side may be reversed. Further, as shown in FIGS. 6 and 7, the primary core 1 may have an outer circumferential portion 1a. With this configuration, a combination of the primary core 1 and the secondary core 3 can provide a complete cylindrical structure having a substantially central column, and the leakage magnetic flux can be further reduced.

Further, as shown in FIGS. 8 and 9, a combination of the primary core 1 and the secondary core 3 may constitute a day-shaped (tripod) core having a square cross section. (Embodiment 2) Another embodiment is shown in FIG. This example
The stepped surface 34 is provided adjacent to the inner side of the front end surface of the central pillar portion 39 to serve as a fitting stopper. When the primary core 1 collides with the stepped surface 34, the magnetic flux inlet / outlet end surface 15 and the central pillar portion 39 are provided. A gap of about 100 μm is formed between the tip surface and the. In this way, both slopes do not mesh with each other, and the primary core 1 can be pulled out easily. (Embodiment 3) Another embodiment is shown in FIG.

This embodiment is a modification of the top plate portion 33 of the first embodiment. That is, the top plate portion 33 of this embodiment
Is a fixed flat plate portion 33a formed to have a constant thickness and extending in a direction perpendicular to the coil axis from the upper end of the end leg portion 32,
An elastic plate portion 33b made of a rubber plate containing soft magnetic particles and attached to the lower surface of the fixed flat plate portion 33a, and a movable plate which is attached to the lower surface of the elastic plate portion 33b and is displaced in the coil axial direction by expansion and contraction of the elastic plate portion 33b. The top plate portion 33 (including the central pillar portion 39) of the first embodiment is formed to have substantially the same outer shape as that of the top plate portion 33c.

With this configuration, the movable plate portion 33c is pressed almost upward by the fitting of the primary core 1, and the elastic plate portion 33 is formed.
b contracts. When the tip of the support portion 5 abuts against the inner surface of the end leg portion 32 and the fitting of the primary core 1 is completed, the elastic plate portion 33b.
Urges the movable plate portion 33c downward, so that the gaps at the magnetic flux inlet / outlet end faces 15 and 16 are reduced or eliminated. The magnetic flux can penetrate from the end leg portion 32 to the side surface of the movable plate portion 33c, and also to the upper surface of the movable plate portion 33c through the fixed flat plate portion 33a and the elastic plate portion 33b. Of course, it is possible to reduce the magnetic resistance between the end leg portion 32 and the movable plate portion 33c by providing irregularities on the upper surface of the movable plate portion 33c and other parts.

In this way, it is possible to reduce the gap length during energization and prevent the primary core 1 and the secondary core 3 from meshing with each other at the magnetic flux inlet / outlet end faces 15 and 16.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a coil shaft center and a primary core fitting direction showing an embodiment of an electromagnetic power supply device of the present invention,

2 is a sectional view of the device of FIG. 1 in a direction perpendicular to the coil axis,

FIG. 3 is a cross-sectional view showing the process of inserting the primary core of the apparatus of FIG.

FIG. 4 is a cross-sectional view showing the device of Example 2,

FIG. 5 is a cross-sectional view showing the device of Example 3,

FIG. 6 is an axial cross-sectional view showing a modification of the device of Example 1;

7 is a sectional view of the device of FIG. 6 in the direction perpendicular to the axis,

FIG. 8 is an axial cross-sectional view showing another modification of the device of the first embodiment,

9 is a sectional view of the device of FIG. 8 in the direction perpendicular to the axis,

[Explanation of symbols]

1 is a primary core, 2 is a primary coil, 3 is a secondary core, 4 is a secondary coil, 15 is a magnetic flux inlet / outlet end surface, and 61 is a guide surface.

Claims (3)

[Claims] 1. A closed magnetic circuit with a gap is formed by a movable primary core around which a primary coil is wound, and a magnetic flux input / output end surface that can be joined to the magnetic flux input / output end surface of the primary core. A secondary core and a secondary coil wound around the secondary core, in an electromagnetic power feeder for an electric vehicle in which the secondary core is disposed in a vehicle body, the primary core is formed in an upright columnar shape, The electromagnetic power supply device for an electric vehicle, wherein the secondary core has a square cross section surrounding the primary core. 2. The primary magnetic core is formed in the vehicle body in the vicinity of the secondary core and has the same plane as at least one of the magnetic flux inlet / outlet end faces of the secondary core, and the primary magnetic core is fitted into the magnetic flux inlet / outlet end faces. The electromagnetic power supply device for an electric vehicle according to claim 1, further comprising a guide surface that guides to the joining position. 3. The electromagnetic power feeder for an electric vehicle according to claim 2, wherein the magnetic flux output / inlet end surface of the primary core has an inclined surface that tapers in the fitting direction.