JPH1198707A - Non-contact charging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact charging device which is so constructed as to eliminate leakage flux through a gap between a charging part side core and a charged part side core. SOLUTION: A non-contact charging device has a primary coil 32 wound on a pillar part 21 of a charging part side core 2 and a secondary coil 82 wound on a pillar part 71 of a charged part side core 7. The primary coil 32 and the secondary coil 82 are arranged close to each other for charging a battery connected to the secondary coil 82. At least either the primary coil 32 or the secondary coil 82 is provided so as to protrude from the pillar part 21 or 71 on which the coil is wound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type charging device for charging a battery connected to a secondary coil by utilizing an electromagnetic induction between a primary coil and a secondary coil.

[0002]

2. Description of the Related Art In recent years, devices equipped with a battery have been diversified, and portable information terminal devices such as mobile phones, small-sized devices with low power consumption such as shavers, and relatively large-sized devices such as electric bicycles have been used. Batteries are mounted even on devices with high power. In general, contact-type charging devices are often used to charge these batteries.

[0003] However, in the contact-type charging device, since the terminal for connecting the charging section connected to the commercial power supply and the charged section having the battery is exposed to the outside, the terminal rusts and oxidizes. , Corrosion and the like may occur to cause poor contact.

[0004] For this reason, there has been proposed a non-contact type charging device for transmitting electric power in a non-contact manner from a charging unit connected to a commercial power supply to a charging unit equipped with a battery. The principle of operation of such a non-contact charging device is that a transformer is configured by arranging a primary coil provided in a charging section and a secondary coil provided in a charged section in proximity to each other, and an electromagnetic induction action between both coils is provided. Is used to transmit power.

[0005] As such a conventional non-contact charging device, for example, Japanese Patent Publication No. Hei 8-502640 discloses a non-contact charging device for charging a battery of an electric vehicle.

As shown in FIG. 8, a primary coil 137 connected to a commercial power supply 140 is arranged in the charging section side core 120, and a battery (not shown) is connected to the charging section side core 170. The secondary coil 187 is disposed.

The charging section side core 120 has a columnar portion 126 projecting from the center, a side wall portion 127 surrounding the columnar portion at a predetermined interval, and a connecting portion 128 connecting the columnar portion 126 and the side wall portion 127. Accordingly, an annular groove 129 surrounded by the columnar portion 126, the side wall portion 127, and the connecting portion 128 is formed. The primary coil 137 is embedded in the groove 129.

On the other hand, the charged part side core 170 has the same shape as the charged part side core 120, and has a columnar part 176 and a side wall part 17.
7, a connecting portion 178, and a groove 179, and a secondary coil 187 is embedded in the groove 179.

In such a configuration, the coil 137,
187 are electromagnetically coupled, but a space is provided between the coils 137 and 187 in the axial direction thereof. In this state, when an electric current flows from the AC power supply to the primary coil 137, an induced electromotive force is generated in the secondary coil 187, and this is the electric power for charging the battery of the charged part.

[0010]

However, as indicated by the arrows in the figure, the magnetic flux coming out of the columnar portion 126 of the charging portion side core 120 is directed toward the columnar portion 176 of the charged portion side core 170, Since there is a material that passes through the gap between the cores 120 and 170 toward the side wall 127 of the charging unit side core 120 (hereinafter, referred to as leakage magnetic flux), there is a problem that charging efficiency is reduced by the leakage magnetic flux. there were.

Further, the leakage flux generates an eddy current on the side wall portion 120 above the primary coil 137, and the temperature of the portion becomes locally high. When a control circuit is arranged around the unit-side core 120, the circuit is adversely affected, and the charging unit-side core 120 is housed in a synthetic resin case or molded with synthetic resin. In this case, there is a problem that they are melted depending on the material. This problem is particularly noticeable in an E-shaped core or a pot-shaped core. However, a rod-shaped core may be problematic depending on the use condition.

The present invention has been made in view of the above problems, and has been made in consideration of the above problem, and has been made to reduce a leakage magnetic flux leaking in a direction interlinking with a primary coil through a gap between a charging section side core and a charged section side core. It is an object of the present invention to provide a non-contact charging device configured to eliminate it.

[0013]

According to the present invention, there is provided a non-contact type charging device comprising: a primary coil disposed on a column of a core of a charging section; and a secondary coil disposed on a column of a core of a charged section. Is a non-contact type charging device that charges a battery connected to a secondary coil by disposing the primary coil and the secondary coil at least one of a primary coil and a secondary coil in a proximity arrangement state for charging. The coil is provided so as to protrude toward the other coil side from the columnar portion where the coil is disposed. With such a configuration, 1
Leakage magnetic flux is blocked at a portion protruding from the columnar portion of the secondary coil or the secondary coil.

At least one of the primary coil and the secondary coil surrounds a gap between the column portion of the core on the charging portion side and the column portion of the core on the portion to be charged when arranged close to each other.
With such a configuration, the primary coil or the secondary coil
The primary coil or the secondary coil from between the two columnar portions surrounding the primary coil
Leakage magnetic flux leaking in the direction interlinking with the next coil is cut off.

Further, at least one of the primary coil and the secondary coil surrounds both the columnar portion of the core on the charging portion side and the columnar portion of the core on the portion to be charged when arranged close to each other. With such a configuration, leakage magnetic flux generated from both columnar portions surrounding the primary coil or the secondary coil is cut off.

The charging section side core and the charged section side core include a columnar section protruding from the center, a pair of legs disposed at predetermined intervals on both sides of the columnar section, The coil is arranged in a concave portion that is constituted by a connecting portion that connects the leg portions, and is surrounded by the columnar portion, the leg portion, and the connecting portion.

The charging unit side core and the charged unit side core are connected to each other by connecting a columnar portion projecting from the center, an annular side wall surrounding the columnar portion at a predetermined interval, and the columnar portion and the side wall portion. The coil is disposed in a groove surrounded by the columnar portion, the side wall portion, and the connecting portion.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be specifically described with reference to the drawings. (First Embodiment) First, the charging section 1 will be described.

As shown in FIGS. 1 and 2, a power cord 12 for connection to a commercial power supply (not shown) is provided from a charging section core 2 in a charging section case 11 made of a synthetic resin in a thick plate shape. Have been withdrawn. The charging unit side case 11 includes first, second, and third engagement holes 13 and 14 as engagement means.
15 are juxtaposed. First and third engagement holes 13, 1
5 is a square hole of the same size. Second engagement hole 14
Is formed larger than the first and third engagement holes 13 and 15.

The charging part side core 2 is molded in the charging part side case 11 and has a prismatic columnar part 2 protruding from the center.
1, a pair of legs 22, 23 arranged in parallel at predetermined intervals in both sides of the columnar portion 21, and a connecting portion 24 connecting the columnar portion 21 and the legs 22, 23. Are formed in a substantially E-shape, and the tip of the columnar portion 21 faces the bottom of the second engagement hole 14, and the tip of the legs 22, 23 faces the bottom of the first and third engagement holes 12, 14. It is arranged to be. The legs 22 and 23 are formed in the same shape as the columnar portion 21. These columnar portion 21, leg portions 22, 23, connecting portion 24
The bobbin 31 is attached in a molded state to the two concave portions 25 surrounded by. Note that ferrite is used as the material of the charging unit side core 2.

The bobbin 31 has a rectangular cylindrical shape made of a non-magnetic material, surrounds the columnar portion 21, and protrudes outward from the tip of the columnar portion 21. The bobbin 31 is
Thick portion 31a that abuts on 2 and 23 to fix bobbin 31
And a thin portion 31 b protruding outward from the columnar portion 21. A primary wire is wound around the entire outer periphery of the thin portion 31 b to form the primary coil 32. The primary coil 32 partially overlaps the tip of the columnar portion 21.

Next, the charged portion 6 will be described. As shown in FIGS. 1 and 2, the charged portion 6 includes a charged portion side core 7 in a thick plate shaped charged portion side case 61 made of a synthetic resin.
, A connection cord 62 for connecting to a battery (not shown) is drawn out. The case 61 to be charged includes
As engagement means, first, second, and third engagement pieces 63, 64, 65 corresponding to the respective engagement holes 13, 14, 15 are provided. The first and third engagement pieces 63, 65 are both prisms of the same size. As will be described later, the second engagement piece 64 includes a bobbin 81 and a secondary coil 8 on the outer periphery of the columnar portion 71.
2 are arranged and formed, so that the first and third engagement pieces 63 and 65 have a prismatic shape thicker than the first and third engagement pieces 63 and 65.

The charged portion side core 7 is connected to the charged portion side case 6.
1 and has substantially the same shape as the charging unit side core 2, and includes a columnar portion 71, legs 72 and 73, and a connecting portion 24, and the columnar portion 71 is provided with a second engagement piece 64. Inside
Legs 72 and 73 are arranged in the first and third engagement pieces 63 and 65, respectively. These columnar portion 71, leg portions 72, 7
3. In the two concave portions 75 surrounded by the connecting portion 74, the bobbin 8
1 is attached.

The bobbin 81 is in the form of a rectangular cylinder made of a non-magnetic material, has a length substantially equal to that of the columnar portion 71, and abuts the outer periphery of the bobbin 81 while surrounding the bobbin 81 with substantially the same length. A conductor is wound around the entire outer periphery of 81 to form a secondary coil 82.

When charging is performed using the charging section 1 and the charged section 6 having the above-described configuration, as shown in FIG. 3 is inserted into the corresponding first, second, and third engagement holes 13, 14, and 15 of the corresponding charging unit side case 11 so that the charging unit side core 2 The charged-part-side cores 7 are superposed and arranged with a distance corresponding to the thickness of each mold.

At this time, the primary coil 32 protrudes outside the columnar portion 21 of the charging portion side core 2, and the protruding portion is the second portion.
Since it is arranged so as to surround the periphery of the engagement hole 14 of
The second engagement piece 64 inserted into the second engagement hole 14 is
It will be surrounded by the next coil 32. Thereby, the columnar portion 71 and the secondary coil 82 of the core 7 to be charged arranged in the second engagement piece 64 are surrounded by the primary coil 32. That is, the primary coil 32 is
In addition, it surrounds both the columnar portions 21 and 71 of the charged portion side core 7 and also surrounds the gap between the tips of the columnar portions 21 and 71.

Therefore, of the magnetic flux generated from the tip of the columnar portion 21 of the charging section side core 2 during charging, the primary coil 32
Although the magnetic flux heading toward the columnar portion 71 of the charged part side core 7 surrounded by the above passes, it passes through the direction interlinking with the primary coil 32, that is, through the gap between the charged part side core 2 and the charged part side core 7. As a result, there is no magnetic flux leaking outward.

Here, the primary coil 32 is connected to the columnar portion 21,
The structure that surrounds not only the gap between the two pillars 71 but also the two pillars 21 and 71 is such that the recess 2 extends from the tip of the pillar 21.
This is to eliminate the leakage magnetic flux generated on the fifth side.

The circuit configuration of the charging section 1 and the charged section 6 having such a configuration will be described below with reference to FIG. Although not shown, a charging primary circuit 4 to be described later includes a charging unit side case 11.
And the secondary charging circuit is arranged on the back surface of the case 61 to be charged.

As shown in FIG. 1, the charging primary circuit 4 disposed in the charging section side case 2 of the charging section 1 includes a full-wave rectifier circuit 41, a smoothing capacitor 42, a switching transistor 43 and the like. The transistor 43 is intermittently driven at predetermined intervals by a drive signal supplied from a drive circuit 44.

On the other hand, the case 61 of the charged part 6 on the part to be charged
The charging secondary circuit 5 disposed in the
1. It is composed of a transistor 52 for charging on / off and the like. The driving of the transistor 52 is controlled by an on / off signal supplied from a charging control circuit 53. The voltage between the terminals of the battery is input to the charge control circuit 53, and while the voltage between the terminals of the battery is lower than a predetermined reference voltage, the transistor 52 is turned on to continue charging, and the charging of the battery is continued. Once the terminal voltage exceeds the reference voltage, the transistor 52 is turned off to stop charging. Thus, overcharging of the battery 50 can be prevented.

In such a configuration, when a current is supplied from the commercial power supply 40 to the charging primary circuit 4, the current is rectified by the full-wave rectifier circuit 41, smoothed by the capacitor 42, Primary coil 32 as the side charging current
Supplied to Here, since the transistor 43 is switched by a high-frequency signal from the drive circuit, the primary-side charging current supplied to the primary coil 32 is a pulse-like current. Thereby, an electromagnetic induction action occurs between the primary coil 32 and the secondary coil 82, and
A high-frequency electromotive force is generated in the next coil 82. The electromotive force is supplied to the charging secondary circuit 5 as a secondary charging current,
After being smoothed by the capacitor 51, the battery 50
, And as a result, the battery 50 is charged.

In the present embodiment, the charging unit side case 11 and the battery are formed separately, and the connection cord 62
Although the description has been given of the case where the
1 and the battery may be integrated.

Further, in the present embodiment, the case where the E-shaped core is used as the charging section side core 2 and the charging section side core 7 has been described. However, the present invention is not limited to this. As shown in FIG. 5, when the leg portions 22 and 23 of the charging portion side core 2 are projected from the columnar portion 21 toward the charged portion 6 side, the charged portion side core 7 of the charged portion 6 becomes T-shaped. be able to. (Second Embodiment) In this embodiment, a pot-shaped core having a shape obtained by rotating an E-shaped core around its columnar portion is used. The power cord 12 and the connection cord 6
2 and the circuit configuration are the same as those in the first embodiment, so that illustration and description thereof are omitted.

As shown in FIG. 5, the charging section side core 20
A column-shaped column 26 protruding from the center, and an annular side wall 27 surrounding the column 26 at a predetermined interval.
Connecting portion 28 connecting between columnar portion 26 and side wall portion 27
A bobbin 36 is attached to a groove 29 surrounded by the columnar portion 26, the side wall portion 27, and the connecting portion 28. In addition, the above-mentioned charging part side core 20, bobbin 36, 1
The entire portion exposed to the outside of the next coil 37 is covered with the resin 91.

The bobbin 36 has a cylindrical shape made of a non-magnetic material, wraps around the column 26, surrounds the column 26, and protrudes outward from the tip of the column 26. The bobbin 36 comes into contact with the side wall 27 and
And a thin portion 36b protruding outward beyond the tip of the columnar portion 26. A conductor is wound around the entire outer periphery of the thin portion 36b, and the primary coil 37 is It is formed. The primary coil 37 wraps around the tip of the columnar portion 26 when viewing the charging section side core 20 from the side.

As shown in FIG. 5, the charged portion side core 70 has the same shape as the charged portion side core 20, and includes a columnar portion 76, a side wall portion 77, and a connecting portion 78. A bobbin 86 is attached along an inner peripheral surface of a groove 79 surrounded by the columnar portion 76, the legs 77, 78, and the connecting portion 78.

The bobbin 86 has a cylindrical shape made of a non-magnetic material. The bobbin 86 is in contact with the periphery of the columnar portion 76 and surrounds the periphery with substantially the same length. The secondary coil 87 is formed by being turned.

Note that the entire portion of the above-described charged portion side core 70, bobbin 86, and secondary coil 87 that are exposed to the outside are covered with a resin mold 92. When charging is performed in such a configuration, as shown in FIG. 6, an annular projecting portion of the primary coil 37 projecting from the charging unit 1 is inserted into the groove 79 of the core 70 to be charged. By doing so, the charged part side core 20 and the charged part side core 70 are arranged at a distance corresponding to the respective mold thicknesses.

At this time, the primary coil 37 protrudes outside the columnar portion 26 of the charging section side core 20, and the protruding portion surrounds the columnar section 76 of the charging section side core 70 and the secondary coil 87. That is, the primary coil 37 surrounds both the columnar portions 26 and 76 of the charged portion side core 20 and the charged portion side core 70, respectively, and thereby surrounds the gap between the two columnar portions 26 and 76.

Accordingly, of the magnetic flux generated from the tip of the columnar portion 26 of the charging section side core 20 during charging, the primary coil 3
The magnetic flux heading toward the columnar portion 76 of the charged portion-side core 70 surrounded by 7 passes, but is linked to the primary coil 37.
That is, there is no magnetic flux leaking outward through the gap between the charged part side core 20 and the charged part side core 70.

In the first and second embodiments, only the primary coil 32 (37) is connected to the columnar portion 21.
(26), the charged part side core 2
The case where the leakage magnetic flux passing through the gap between (20) and the charged part side core 7 (70) is prevented has been described, but only the secondary coil 82 (87) or the primary coil 32 (37) and the secondary coil 82 (87) are used. By projecting both of the coils 82 (87), it is also possible to prevent leakage magnetic flux passing through the gap between the charged part side core 2 (20) and the charged part side core 7 (70).

[0043]

According to the contactless charging device of the present invention, 1
Improves charging efficiency by eliminating leakage magnetic flux leaking in the direction intersecting with the primary or secondary coil through the gap between the charged part side core and the charged part side core in the secondary coil or secondary coil Can be done.

Furthermore, since no eddy current is generated due to the leakage magnetic flux, there is no locally high temperature portion, local deterioration due to heat is avoided, and the durability of the device can be improved. Even when the core or the like is housed in the case or molded with resin, the case and the resin are not melted, and even when the circuit is arranged around the coil, the core, and the like. Since the characteristics of the circuit elements are not changed by heat, the reliability of the device can be improved.

Further, it is not necessary to separately arrange a structure for eliminating the leakage magnetic flux, and the leakage magnetic flux can be eliminated with a simple structure in which the primary coil or the secondary coil projects from the core.

[Brief description of the drawings]

FIG. 1 is a perspective view of a non-contact charging device according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of the non-contact charging device of FIG.

FIG. 3 is a partially cutaway perspective view of the contactless charging device of FIG. 1 in a charged state.

FIG. 4 is a block diagram illustrating a circuit configuration of the non-contact charging device of FIG.

FIG. 5 is a partially cutaway perspective view showing a non-contact charging device according to a second embodiment of the present invention.

6 is a partially cutaway perspective view of the contactless charging device of FIG. 5 in a charged state.

FIG. 7 is a partially cutaway perspective view of a non-contact charging device according to another embodiment of the present invention.

FIG. 8 is a partially cutaway perspective view showing a conventional non-contact charging device.

[Explanation of symbols]

 2: Charging part side core 21: Column part 22, 23: Leg part 24: Connection part 25: Concave part 32: Primary coil 7: Charged part side core 71: Column part 72, 73: Leg part 74: Connection part 75 : Recess 82: primary coil

Claims (5)

[Claims] 1. A primary coil disposed on a pillar of a charged part side core and a secondary coil disposed on a pillar of a charged part side core are arranged close to each other to connect to the secondary coil. A non-contact type charging device for charging a charged battery, wherein in the close arrangement state for the charging, at least one of the primary coil and the secondary coil is other than the columnar portion where the coil is arranged. A non-contact type charging device, which is provided so as to protrude toward a coil side of the charging device. 2. At least one of the primary coil and the secondary coil surrounds a gap between the columnar portion of the charging portion side core and the columnar portion of the charged portion side core in the close arrangement. The non-contact charging device according to claim 1, wherein 3. At least one of the primary coil and the secondary coil surrounds both the columnar portion of the charging portion side core and the columnar portion of the charged portion side core in the close arrangement. The non-contact charging device according to claim 2, wherein 4. The charging section-side core and the charged section-side core have a columnar portion projecting from the center, a pair of legs disposed at predetermined intervals on both sides of the columnar portion, and 4. A coil, comprising: a connecting portion that connects a columnar portion and the leg portion; wherein the coil is disposed in a concave portion surrounded by the columnar portion, the leg portion, and the connecting portion.
A non-contact charging device according to any one of the above. 5. The charging section-side core and the charged section-side core have a columnar portion protruding from the center, an annular side wall surrounding the columnar portion at a predetermined interval, and the columnar portion and the columnar portion. The connecting part which connects a side wall part is comprised, The said coil is arrange | positioned in the groove part surrounded by the said columnar part, the said side wall part, and the said connection part, The coil is arrange | positioned in any one of the Claims 1 thru | or 3 characterized by the above-mentioned. Contact type charging device.