CN209963837U

CN209963837U - Wireless charging device

Info

Publication number: CN209963837U
Application number: CN201921096950.3U
Authority: CN
Inventors: 徐月朗; 黄家毅; 马宗俊
Original assignee: Dongguan Mentech Optical and Magnetic Co Ltd
Current assignee: Dongguan Mentech Optical and Magnetic Co Ltd
Priority date: 2019-07-12
Filing date: 2019-07-12
Publication date: 2020-01-17
Anticipated expiration: 2029-07-12

Abstract

The utility model provides a wireless charging device, which comprises a magnet and an induction coil module arranged on the magnet; the induction coil module comprises at least two main coils and at least one auxiliary coil for partially demagnetizing the main coils, any main coil is adjacent to or overlapped with at least one auxiliary coil in an intersecting way, and any main coil is matched with at least one auxiliary coil to form a coil group for charging an electronic product; the auxiliary coil is a short-circuit coil, or is electrified to generate a counter magnetic field so as to weaken part of the magnetic field of the corresponding main coil, and the strength of the counter magnetic field is controlled by the strength of the electrified current. The utility model discloses wireless charging device can improve transmission efficiency, realizes charging simultaneously for two or more than two electronic products.

Description

Wireless charging device

Technical Field

The utility model belongs to the technical field of the wireless charging technique and specifically relates to a wireless charging device is related to.

Background

The Wireless charging technology (Wireless charging technology) is derived from a Wireless power transmission technology, so that the charger is free from the limitation of a line, and the complete separation of an electric appliance and a power supply is realized. The charger shows better advantages than the conventional charger in the aspects of safety, flexibility and the like.

At present, the wireless charging technology mainly comprises an electromagnetic induction technology and magnetic field resonance, wherein the application range of the electromagnetic induction technology (WPC Qi standard) is the widest, but the charging distance is less than 5 cm. Along with the development in the wireless charging market, electronic products such as mobile phones, intelligent bracelet, intelligent wrist-watch can both support wireless charging now, realize "along with putting along with filling, take away and use. But the utility model discloses the people is in research and practice to prior art, it can only realize charging for single electronic product to discover current wireless battery charging outfit, use single coil can only support an electronic product to charge, if adopt the coil that the wire winding area is big, though can increase battery charging outfit's charging area and increase the charging position, but because the coil of another electronic product is fixed, the magnetic leakage is many and lead to transmission efficiency lower, if increase coil quantity and charge simultaneously in order to supply two or more than two electronic products, then can lead to charging efficiency low and the coil to generate heat too big because the magnetic field interference between the coil, consequently, be difficult to realize effectively charging for two or more than two electronic products simultaneously.

SUMMERY OF THE UTILITY MODEL

The utility model provides a wireless charging device can improve transmission efficiency to solve two or more than two technical problem that magnetic field interfered between the coil when electronic product charges simultaneously, the utility model discloses can effectively improve charge efficiency and reduce and generate heat, realize charging simultaneously for two or more than two electronic product.

In order to solve the above technical problem, an embodiment of the present invention provides a wireless charging device, including a magnet and an induction coil module disposed on the magnet; the induction coil module comprises at least two main coils and at least one auxiliary coil for partially demagnetizing the main coils, any main coil is adjacent to or overlapped with at least one auxiliary coil in an intersecting way, and any main coil is matched with at least one auxiliary coil to form a coil group for charging an electronic product; the auxiliary coil is a short-circuit coil, or is electrified to generate a counter magnetic field so as to weaken part of the magnetic field of the corresponding main coil, and the strength of the counter magnetic field is controlled by the strength of the electrified current.

Preferably, the induction coil module comprises two main coils and one auxiliary coil located between the two main coils.

Preferably, the induction coil module includes two coil groups arranged in a staggered manner on an upper layer and a lower layer, and each coil group includes one main coil and one auxiliary coil.

Preferably, the induction coil module comprises one auxiliary coil and four main coils arranged around the auxiliary coil.

Preferably, the wireless charging device further includes a first coil for removing a center charging blind spot, the first coil is disposed in the middle of the four main coils, and a radius of the first coil is smaller than that of the auxiliary coil.

Preferably, the wireless charging device further includes a second coil for increasing central charging power, the second coil is disposed in the middle of the four main coils, and the radius of the second coil is larger than that of the first coil and smaller than or equal to that of the auxiliary coil.

Preferably, the start-tail lines of any one of the main coils and any one of the auxiliary coils are twisted into a twist shape.

Preferably, the starting wire and the tail wire of any one of the main coils and the auxiliary coils are sleeved with heat-shrinkable sleeves.

Preferably, the shape of the inner hole of any main coil is one of circular, oval, racetrack and rectangular; the inner hole of any auxiliary coil is in one of a circular shape, an oval shape, a racetrack shape and a rectangular shape.

Preferably, the area of the magnet is larger than that of the induction coil module, and a back plate is arranged at the bottom of the magnet.

Compared with the prior art, the embodiment of the utility model provides a have following beneficial effect:

the main coil is used as a transmitting coil for wireless charging, generates a magnetic field after being electrified, and enables a receiving coil of an electronic product to generate electric energy in a magnetic induction mode, so that wireless charging is realized. The auxiliary coil is arranged beside the main coils, has a demagnetization effect on magnetic leakage of the main coils, can effectively weaken mutual interference of magnetic fields between the two main coils, improves the transmission efficiency of the wireless charging device and reduces the heating of the coils.

The main coil and the auxiliary coil have multiple combination modes, one coil group comprises one main coil and at least one auxiliary coil, and one coil group charges an electronic product. The combination mode can be that one auxiliary coil is in the middle, two or more than two main coils are shared and play the role of demagnetization, or a single main coil is configured with at least one auxiliary coil to form a coil group, and the combination mode is various and flexible. Therefore, when the wireless charging device is used for charging two electronic products simultaneously, two main coils and at least one auxiliary coil need to be configured; when the wireless charging device charges three or more electronic products, three or more main coils and at least one auxiliary coil are required.

In addition, the auxiliary coil can realize the demagnetization effect through the short circuit of the coil, and can also generate a main coil magnetic field and magnetic lines opposite to the nearby magnetic field and magnetic lines when the coil is electrified, so that the magnetic lines of the main coil are partially cancelled; the strength of the counter magnetic field of the auxiliary coil is controlled by the strength of the electrified current, so that the strength of the counter magnetic field is controlled by adjusting the current, and the magnetic field weakening effect of the main coil is further controlled.

Drawings

Fig. 1 is a schematic structural diagram of a wireless charging device in an embodiment of the present invention;

fig. 2 is an exploded view of a wireless charging device in an embodiment of the present invention;

fig. 3 is a top view of a wireless charging device in an embodiment of the invention;

FIGS. 4a to 4b show the positional relationship between the main coil and the auxiliary coil;

FIGS. 5 a-5 b show two coil sets of two primary coils and one secondary coil;

FIG. 6 is a diagram showing the magnetic field in the upper region of FIGS. 5a and 5 b;

figure 7 is a schematic combination of embodiment three in an example of the invention;

figure 8 is a schematic combination diagram of embodiment four in an example of the invention;

FIG. 9 is a front view of FIG. 8;

figure 10 is a schematic combination of embodiment five in an example of the invention;

FIG. 11 is a front view of FIG. 10;

FIG. 12 shows three shape design diagrams of the main coil or the auxiliary coil;

wherein the reference numbers in the drawings of the specification are as follows:

1. a main coil; 2. an auxiliary coil; 3. a magnet; 4. a back plate; 5. a first coil; 6. a second coil; 7. and (4) heat-shrinkable tubing.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Referring to fig. 1 to 4a, a preferred embodiment of the present invention provides a wireless charging device, which includes a magnet 3 and an induction coil module disposed on the magnet 3; the induction coil module comprises at least two main coils 1 and at least one auxiliary coil 2 used for partially demagnetizing the main coils 1, any main coil 1 is adjacent to or overlapped with at least one auxiliary coil 2 in an intersecting way, and any main coil 1 is matched with at least one auxiliary coil 2 to form a coil group used for charging an electronic product; the auxiliary coil 2 is a short circuit coil, or is electrified to generate a counter magnetic field to weaken part of the magnetic field corresponding to the main coil 1, and the strength of the counter magnetic field is controlled by the strength of the electrified current.

In this embodiment, the main coil 1 is used as a transmitting coil for wireless charging, generates a magnetic field after being powered on, and enables a receiving coil of an electronic product to generate electric energy through a magnetic induction manner, thereby realizing wireless charging. The auxiliary coil 2 is arranged beside the main coil 1, has a demagnetization effect on magnetic leakage of the main coil 1, can effectively weaken mutual interference of magnetic fields between the two main coils 1, improves the transmission efficiency of the wireless charging device and reduces coil heating.

The main coil 1 and the auxiliary coil 2 have various combination modes, one coil group comprises the main coil 1 and at least one auxiliary coil 2, and one coil group is used for charging an electronic product. Two or more main coils 1 can play a role in demagnetization in the middle of one auxiliary coil 2, or at least one auxiliary coil 2 can be configured on a single main coil 1 to form a coil group, and the combination form is various and flexible. Therefore, when the wireless charging device is used for simultaneously charging two electronic products, two main coils 1 and at least one auxiliary coil 2 need to be configured; when the wireless charging device charges three or more electronic products, three or more main coils 1 and at least one auxiliary coil 2 are required.

The auxiliary coil 2 can realize the demagnetization effect through the short circuit of the coil, and can also generate a magnetic field and magnetic lines of force of the main coil 1 opposite to the side by electrifying the coil, so that the magnetic lines of force of the main coil 1 are partially cancelled; the strength of the counter magnetic field of the auxiliary coil 2 is controlled by the strength of the electrified current, so that the strength of the counter magnetic field is controlled by adjusting the current, and the magnetic field weakening effect of the main coil 1 is further controlled. Of course, it is also possible to use a permanent magnet instead of the auxiliary coil 2, which generates an upward magnetic field, the magnetic lines of the main coil 1 and the permanent magnet being opposite and partly cancelled, but it is not possible to adjust the strength of the magnetic field using a permanent magnet.

In the embodiment of the present invention, it should be noted that the area of the magnet 3 is larger than the area of the induction coil module, the material of the magnet 3 is soft magnetic ferrite, and since soft magnetic has a saturation characteristic, in order to ensure that no saturation occurs, the thickness specification is:

t>Lm*Imax/(0.7*N*Bs*lc)，

wherein lc is the perimeter of an inner hole of the coil, Lm is the inductance value of the coil, Imax is the maximum current for the coil to work, N is the number of turns of the coil, and Bs is the maximum saturation flux density of the soft magnetic ferrite.

The bottom of the magnet 3 is provided with a back plate 4, the material of the back plate 4 is preferably aluminum, but other plastics are also available, the back plate 4 is mainly used for supporting the magnet 3, and the magnet 3 is fixed on the back plate 4 through glue or other adhesives, so that the mechanical strength of the magnet 3 is increased. If the material of the back plate 4 is metal, such as aluminum, the heat dissipation performance can be increased while the support function is maintained.

Referring to fig. 1, the start-tail lines of any main coil 1 and any auxiliary coil 2 are twisted, and the start-tail lines are twisted together to form a twist shape. Two insulated wires are twisted together, interference signals (common mode signals) act on the two wires which are twisted together uniformly, and the common mode signals can be eliminated in a differential circuit for receiving signals, so that useful signals (differential mode signals) are extracted, and EMI can be effectively reduced. The number of turns and the size of the main coil 1 and the auxiliary coil 2 are designed according to actual requirements, and in the present embodiment, the number of turns of the main coil 1 and the auxiliary coil 2 is preferably 1: 1.

Referring to fig. 1 to 3, in order to rationalize the structure, the heat-shrinkable sleeve 7 is sleeved on the starting wire and the tail wire of any main coil 1 and any auxiliary coil 2. After the pigtail is twisted with the twisted twine, the twisted twine is easy to loosen, the pigtail can be fixed by the heat-shrinkable sleeve 7, the loosening of the pigtail is avoided, and the insulation effect of the pigtail can be enhanced. Meanwhile, the hot-dip tinning is carried out on the end terminal of the starting tail wire, so that the damage caused by the burning back of a wire paint film is avoided.

Referring to fig. 12, in the present embodiment, the inner hole of any main coil 1 is one of a circle, an ellipse, a racetrack, a rectangle, and the like; any auxiliary coil 2's hole shape is one of them of shapes such as circular, oval, runway shape, rectangle, and the technical personnel in the field are in the utility model discloses a design to the coil shape on the basis is all in the utility model discloses a within range is not repeated here.

The embodiment of the utility model provides an in, the coil assembly of induction coil module realizes charging for electronic product, and in the coil assembly, main coil 1, auxiliary coil 2's relation of connection mainly has following two kinds:

first, as shown in fig. 4a, the main coil 1 is adjacent to the auxiliary coil 2;

secondly, as shown in fig. 4b, the main coil 1 and the auxiliary coil 2 are overlapped in an intersecting manner.

In order to realize simultaneous charging of two or more electronic products, two or more coil groups are required, and the combination of the main coil 1 and the auxiliary coil 2 mainly includes the following five types:

the first embodiment simultaneously charges 2 electronic products:

referring to fig. 5a to 5b, the induction coil module includes two main coils 1 and an auxiliary coil 2 disposed between the two main coils 1. The principle of the auxiliary coil 2 as a short-circuit coil is described below with reference to fig. 6:

the auxiliary coil 2 is in the middle position, in the upper area of the auxiliary coil 2, due to the short circuit of the auxiliary coil, after the auxiliary coil 2 is coupled with the main coil 1 on the left side, the magnetic field on the area of the auxiliary coil 2 is weak, so that the area becomes a charging blind spot, similarly, the coupling part area of the auxiliary coil 2 and the main coil 1 on the right side becomes the charging blind spot, and the part without coupling between the main coil 1 and the auxiliary coil 2 on the two sides can be used for charging, so that the two electronic products can be charged simultaneously.

The second embodiment charges 2 electronic products at the same time:

referring back to fig. 1 and 2, the induction coil module includes two coil sets disposed alternately on the upper and lower layers, each coil set including a main coil 1 and an auxiliary coil 2. The main coil 1 and the auxiliary coil 2 positioned on the lower layer form a coil group, the main coil 1 and the auxiliary coil 2 positioned on the upper layer form another coil group, the staggered design is adopted, the mutual interference of the two main coils 1 is reduced to the minimum, and simultaneously, the demagnetization can be realized by utilizing the demagnetization effect of the auxiliary coil 2 respectively, so that two electronic products can be charged simultaneously.

The third embodiment charges 4 electronic products at the same time:

referring to fig. 7, the induction coil module includes an auxiliary coil 2 and four main coils 1 disposed around the auxiliary coil 2. The four main coils 1 surround an auxiliary coil 2, the coupled part between the auxiliary coil 2 and the main coil 1 is a charging blind spot of the main coil 1, and the non-coupled part is a chargeable area. Therefore, through the combination mode, 4 electronic products can be charged simultaneously, the compactness of the charging device can be improved, the number of coils is reduced, and the product structure is optimized.

The fourth embodiment charges 5 electronic products simultaneously:

referring to fig. 8 to 11, in consideration of the charging blind spot existing in the middle region, on the basis of the third embodiment, a first coil 5 for removing the central charging blind spot is added at the center position, the first coil 5 is disposed in the middle of the four main coils 1, and the radius of the first coil 5 is smaller than that of the auxiliary coil 2. When the electronic product is placed above the first coil 5, the chip of the wireless charging device detects that the charging device is arranged, the first coil 5 is powered on and starts to wirelessly charge the electronic product, and therefore 5 electronic products are charged simultaneously.

Fifth, 5 electronic products were charged simultaneously:

with continued reference to fig. 8 to 11, as a further improvement of the fourth embodiment, in order to improve the charging efficiency of the central area without affecting the surrounding charging devices by considering that the charging efficiency is lower due to the smaller size of the first coil 5, the second coil 6 of the central charging power is increased, the second coil 6 is disposed in the middle of the four main coils 1, and the radius of the second coil 6 is larger than that of the first coil 5 and smaller than or equal to that of the auxiliary coil 2. The second coil 6 is adapted to a larger conductor, with interleaved switching control, the general control method is as follows:

when the equipment to be charged is positioned in the central area, controlling the first coil 5 and the second coil 6 to perform power-on and power-off circulation in n periods T;

in a first time period of each period T, the first coil 5 is conducted, the current of the first coil 5 is controlled to gradually increase to a preset first current value, and the second coil 6 is kept powered off;

in a second time period of each period T, controlling the current of the first coil 5 to gradually decrease to zero; and keeping the second coil 6 deenergized;

in a third time period of each period T, the second coil 6 is conducted, the current of the second coil 6 is controlled to gradually increase to a preset second current value, and the first coil 5 is kept powered off;

and controlling the current of the first coil 5 to gradually reduce to zero in a second time period of each period T, and keeping the first coil 5 powered off.

Preferably, the following specific control methods can be used for the interleaved switching:

in a period T, T/4 time, the first coil 5 is conducted to increase the current; T/4-T/2, the current of the first coil 5 gradually becomes zero to open the circuit, then, T/2-3T/4, the first coil 5 does not work, the second coil 6 works to gradually increase the current, 3T/4-T, and the current of the second coil 6 gradually becomes zero. The second coil 6 is added to make up for the defect of small power of the first coil 5, the working time of the first coil 5 can be less than T/2, wherein the second coil 6 works only after the first coil 5 starts to work. Further, in order to increase the inductance value of the first coil 5, a soft magnetic sheet may be added to the bottom of the first coil 5, or a cylindrical soft magnetic sheet may be placed in the middle. Therefore, the fifth embodiment can simultaneously charge five electronic products.

The foregoing is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations are also considered as the protection scope of the present invention.

Claims

1. A wireless charging device is characterized by comprising a magnet and an induction coil module arranged on the magnet; the induction coil module comprises at least two main coils and at least one auxiliary coil for partially demagnetizing the main coils, any main coil is adjacent to or overlapped with at least one auxiliary coil in an intersecting way, and any main coil is matched with at least one auxiliary coil to form a coil group for charging an electronic product; the auxiliary coil is a short-circuit coil, or is electrified to generate a counter magnetic field so as to weaken part of the magnetic field of the corresponding main coil, and the strength of the counter magnetic field is controlled by the strength of the electrified current.

2. The wireless charging apparatus of claim 1, wherein the induction coil module comprises two of the primary coils and one of the secondary coils located intermediate the two primary coils.

3. The wireless charging device as claimed in claim 1, wherein the induction coil module comprises two coil sets disposed alternately on the upper layer and the lower layer, each of the coil sets comprising one of the main coil and one of the auxiliary coils.

4. The wireless charging apparatus of claim 1, wherein the induction coil module comprises one of the auxiliary coils and four of the main coils disposed around the auxiliary coil.

5. The wireless charging device of claim 4, further comprising a first coil for de-centering the charging blind spot, wherein the first coil is disposed in the middle of the four primary coils, and wherein the first coil has a smaller radius than the auxiliary coil.

6. The wireless charging apparatus as claimed in claim 5, further comprising a second coil for increasing a central charging power, the second coil being disposed at a middle of the four main coils, and having a radius larger than that of the first coil and smaller than or equal to that of the auxiliary coil.

7. The wireless charging device according to any one of claims 1 to 6, wherein the start-tail line of any one of the main coils and the auxiliary coil is twisted into a twist shape.

8. The wireless charging device of claim 7, wherein a heat-shrinkable sleeve is sleeved on the starting wire of any one of the main coils and the auxiliary coil.

9. The wireless charging apparatus of any one of claims 1-6, wherein the shape of the inner hole of any one of the primary coils is one of circular, elliptical, racetrack, and rectangular; the inner hole of any auxiliary coil is in one of a circular shape, an oval shape, a racetrack shape and a rectangular shape.

10. The wireless charging device of any one of claims 1-6, wherein the area of the magnet is larger than the area of the induction coil module, and a back plate is arranged at the bottom of the magnet.