KR20180036350A - Low Frequency Antenna Module and keyless entry system including the same - Google Patents

Abstract

Provided are a low frequency antenna module capable of improving assembly and productivity and a keyless entry system including the same. According to an exemplary embodiment of the present invention, the low frequency antenna module comprises: a magnetic core; a coil wound in the circumferential direction of the magnetic core and disposed on a side part of the magnetic core; a pair of magnetic sheets respectively coupled to upper and lower surfaces of the magnetic core to cover the upper and lower surfaces of the coil; and a base member having a pair of connection terminals to which both ends of the coil are connected.

Description

[0001] The present invention relates to a low-frequency antenna module and a keyless entry system including the low-

The present invention relates to a low frequency antenna module and a keyless entry system including the same, and more particularly, to a low frequency antenna module applicable to a keyless entry system for wirelessly operating locking or opening a door of a car, and a keyless entry system .

As the level of living has improved and the supply of cars has increased, the car has now become a necessity for daily life. As a result, there have been a lot of researches on various techniques for opening and starting a vehicle such as a car, a vehicle anti-theft device and a door of a vehicle. For example, a keyless entry method and a keyless start ).

The keyless entry method is a method in which the driver releases the door lock without operating any key or remote control. When the key is held in the body of the driver, the key is automatically transmitted to the electronic authentication device inside the vehicle and the lock is released when the data is authenticated.

An antenna module used in such a keyless entry system is generally configured such that a coil is wound around a bar-type ferrite core and a plurality of antenna modules are mounted at predetermined positions.

Accordingly, when the reception antenna of the smart key is constituted by a single antenna coil, the communication distance (the distance at which data can be received at the vehicle side) is extremely high depending on the positional relationship with the direction of the magnetic field generated in the transmission antenna of the vehicle And there is a problem that communication can not be performed in the worst case.

That is, the reception antenna built in the smart key has a problem that reception sensitivity becomes worse when the axial direction of the antenna coil and the direction of the magnetic field generated by the transmission antenna of the vehicle are parallel to each other and the reception sensitivity is good and when they are orthogonal to each other.

Therefore, it is necessary to provide a non-directional characteristic so that the signal transmitted from the vehicle at all times can be received in a stable state at the receiving antenna of the smart key regardless of the position of the vehicle with respect to the antenna.

To solve this problem, a three-axis antenna module has been proposed in which three coils are arranged orthogonally to each other so as to receive signals in all directions.

For example, a three-axis antenna module is configured by winding a coil on a bar-shaped magnetic core to form an X-axis and Y-axis antenna module, and winding a coil on a side of a hexahedron formed by the magnetic core to arrange a Z- .

In the case of the antenna module for the Z axis, a method of improving the characteristics of the coil by arranging the coil by machining the groove on the side of the hexahedron has been proposed.

However, cracks are generated or broken in the process of forming the grooves on the side of the hexahedron, and the permeability is changed to fail to satisfy the initial design value. In addition, since a separate processing step is required, there is a problem that productivity is lowered.

KR 10-2010-0079607 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide a low frequency antenna module and a keyless entry system including the low frequency antenna module.

In order to solve the above-described problems, the present invention provides a magnetic core comprising: a magnetic core; A coil wound along the circumferential direction of the magnetic core and disposed on a side of the magnetic core; A pair of magnetic sheets respectively coupled to upper and lower surfaces of the magnetic core so as to cover the upper and lower surfaces of the coil; And a base member having a pair of connection terminals to which both ends of the coil are connected.

The magnetic core may have protrusions protruding from a top surface and a bottom surface of the magnetic core, the insertion holes being formed in a region corresponding to the protrusion on the side of the magnetic sheet, The protrusion can be inserted into the insertion hole when the coupling is engaged.

In addition, the magnetic sheet may be divided into a plurality of fine pieces, and the fine pieces may be irregular. For example, the magnetic sheet may be a ferrite sheet.

Further, an adhesive member may be interposed on the opposing surfaces of the magnetic sheet and the magnetic core.

In addition, the base member may have a through hole formed in a region corresponding to the protruding portion, and the protruding portion may be inserted into the engagement hole.

For example, the base member may be a circuit board on which the pair of connection terminals are formed, and the connection terminal may include a coil binding opening through which the end of the coil is wound.

As another example, the base member may be made of an insulating resin, and the pair of connection terminals may be insert molded.

At this time, the base member may include a side wall portion extending upward from the rim at a predetermined height, and the side wall portion may prevent the coil from being exposed to the outside by surrounding the side portion of the coil, And a coil binding port protruding from the coil and winding the end of the coil.

The side wall part may be formed with a wire arrangement groove that is drawn inward on the upper surface thereof, and a lead part extending from the body of the coil and wound around the coil binding hole may be disposed.

Meanwhile, the low-frequency antenna module may be embedded in a smart key, embedded in a portable terminal, or embedded in a wearable device such as a smart watch.

In another embodiment, the low-frequency antenna module of the receiver and the transmitter constituting the keyless entry system may be embedded in the receiver to implement a keyless entry system.

According to the present invention, since the antenna module can be configured through an assembling method, it is possible to prevent breakage and deformation of the magnetic core, which may occur during processing, thereby enhancing reliability and increasing work productivity.

1 is a schematic view of a low-frequency antenna module according to an embodiment of the present invention,
FIG. 2 is a sectional view of FIG. 1,
Fig. 3 is a sectional view of Fig. 1,
4 is a schematic view illustrating a low-frequency antenna module according to another embodiment of the present invention.
FIG. 5 is an illustration of the separation of FIG. 4,
FIG. 6 is a cross-sectional view of FIG. 4,
7 is a plan view showing a case where a magnetic sheet applied to the low frequency antenna module according to the present invention is divided into a plurality of micro pieces.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

1 and 4, the low frequency antenna module 100 and 200 according to an embodiment of the present invention includes a magnetic core 110, a coil 120, a magnetic sheet 130, and a base member 140 and 240 .

The magnetic core 110 shields an electromagnetic field generated from the coil 120 to serve as an inductor core.

For this, the magnetic core 110 may be made of sintered ferrite such as Mn-Zn, Ni-Zn, or Ni-Cu-Zn, but not limited thereto, and dust cores may be used. It is noted that any material having magnetism can be used. In addition, the magnetic core 110 may be a soft magnetic alloy having an amorphous or nanocrystal structure.

The magnetic core 110 may support the coil 120 disposed in the side of the coil 120 (see FIGS. 3 and 6).

The magnetic core 110 includes at least one protrusion 112a and 112b protruding from the upper surface and the lower surface of the magnetic core 110 so as to protrude from the upper surface and the lower surface of the magnetic core 110, And can be coupled with the sheet 130 (see Figs. 2 and 5).

That is, the pair of magnetic sheets 130 may be coupled to the magnetic core 110 by inserting an insertion hole 130a having a predetermined area at a position corresponding to the protrusions 112a and 112b.

The protrusions 112a and 112b and the insertion hole 130a may be formed at the center of the magnetic core 110 and the magnetic sheet 130. The protrusions 112a and 112b, It is to be understood that the present invention is not limited thereto and that the position and the number may be appropriately changed if they can be coupled to each other.

Accordingly, since the magnetic core 110 according to the present invention has protrusions 112a and 112b protruding in the direction parallel to the height direction on the top and bottom surfaces, the sintering operation using the mold can be performed, thereby improving the productivity. In addition, since the conventional process of polishing or cutting a part of the magnetic core 110 to form the receiving groove for disposing the coil 120 is omitted, the process is simplified, and the magnetic core (not shown) Such as cracking or breakage, of the semiconductor device 110.

The coil 120 is for generating a signal in a predetermined frequency band to perform low frequency communication, and a conductive member having a predetermined wire diameter may be wound a plurality of times in a loop shape having a hollow portion having a predetermined area inside .

For example, the coil 120 may be disposed on the side of the magnetic core 110 by being wound a plurality of times in the same direction as the circumferential direction of the magnetic core 110. The hollow portion of the coil 120, And may be the same size as the core 110.

Accordingly, when the magnetic core 110 is inserted into the hollow portion of the coil 120, the inner surface of the coil 120 wound plural times can be closely attached to the side of the magnetic core 110.

Accordingly, the low-frequency antenna modules 100 and 200 according to the present invention can stably receive signals transmitted in the Z-axis direction parallel to the height direction of the magnetic core 110.

Here, the coil 120 may be made of an enameled wire that is enameled outside of a copper wire having a predetermined wire diameter. However, it should be noted that the material of the coil is not limited thereto, and any material can be used as long as the conductive material is covered with an insulating layer.

At this time, the coil 120 disposed on the side of the magnetic core 110 may be covered with the magnetic sheet 130 on the upper and lower surfaces of the coil body which is wound a plurality of times.

The pair of magnetic sheets 130 are formed to have an area relatively larger than the areas of the upper and lower surfaces of the magnetic core 110 so that the edge of the magnetic sheet 130 contacts the magnetic core 110, So as to protrude outward from the rims of the upper and lower surfaces (see Figs. 3 and 6).

The side walls of the magnetic core 110 and the sides of the magnetic core 110 when the magnetic sheet 130 and the magnetic core 110 are coupled to each other, A space may be formed, and the coil 120 may be disposed on the accommodation space side.

When the coil 120 is disposed in the receiving space, the inner surface, the upper surface, and the bottom surface of the coil 120 are electrically connected to the magnetic core 110 and the magnetic sheet 130 And the radiation path of the electromagnetic field generated by the coil 120 is limited to the side of the magnetic core 110, thereby improving the radiation characteristic of the coil 120. [ Accordingly, the low-frequency antenna modules 100 and 200 according to the present invention can improve reception sensitivity in a desired direction.

The magnetic sheet 130 shields an electromagnetic field generated from the coil 120. To this end, the magnetic sheet 130 may be made of a magnetic material so as to shield an electromagnetic field generated from the coil 120. For example, the magnetic sheet 130 may be a ferrite sheet, a polymer sheet, an amorphous ribbon sheet, a nanocrystalline ribbon sheet, or the like. However, it should be noted that the magnetic sheet 130 is not limited thereto, and any known magnetic material may be used.

The magnetic sheet 130 may be provided in the form of a plate having a predetermined area. The magnetic sheet 130 may be formed in a shape of a plate such that the edge of the magnetic sheet 130 protrudes outward from the upper and lower surfaces of the magnetic core 110 Of the upper surface and the lower surface of the lower surface.

In addition, the magnetic sheet 130 may be inserted through the insertion hole 130a for coupling with the magnetic core 110 on the inner side as described above.

The magnetic sheet 130 is bonded to the upper surface or lower surface of the magnetic core 110 via the adhesive member 131 interposed between the magnetic core 110 and the magnetic core 110 through the insertion hole 130a. And can be attached and fixed. Here, a portion of the magnetic sheet 130 protruding outward from the top and bottom rims of the magnetic core 110 may be directly attached to a part of the coil 120 disposed in the accommodation space via an adhesive layer.

Meanwhile, the magnetic sheet 130 may be divided into a plurality of fine pieces so as to improve flexibility, and the plurality of fine pieces may be irregularly formed (see FIG. 7). In addition, the pair of protective films 132 are attached to both sides of the magnetic sheet 130 via the adhesive member 131, so that the position of the fine pieces can be fixed through the adhesive member 131. Here, at least one of the pair of protective films 132 may be a release film that is removed during the attachment process.

For example, the magnetic sheet 130 may be formed of a ferrite sheet, and the ferrite sheet may be flaked to form a plurality of micro-pieces. As a result, the flexibility of the ferrite sheet having a high brittleness is improved, so that cracking or cracking can be prevented from occurring when the ferrite sheet is attached to the magnetic core 110, and occurrence of cracks or cracks can be minimized. Thus, it is possible to prevent the characteristic of the initial design value from being changed or to minimize the characteristic change.

Although not shown in the figure, on the side of the magnetic sheet 130 disposed on the opposite side of the base members 140 and 240 with respect to the magnetic core 110 among the pair of magnetic sheets 130, An opening that is formed to pass through the region may be formed. Such an opening can further improve the reception sensitivity by providing a path through which an electromagnetic field generated from the coil 120 is discharged to the outside or an electromagnetic field emitted from the outside can flow into the coil 120 side. It is noted that the opening may be in the form of an annular shape or a discontinuous arcuate or straight slit.

The base member 140 and 240 may be disposed on one side of the pair of magnetic sheets 130 to provide a power source supplied from the outside to the coil 120, Lt; / RTI >

For this purpose, the base member 140 and 240 may be formed with a coupling hole 142 for coupling with the protrusion 112b formed in the magnetic core 110, and the coupling hole 142 may be formed through the magnetic sheet 130 formed in the insertion hole 130a. Accordingly, the magnetic core 110, the magnetic sheet 130, and the base members 140 and 240 can be simultaneously clamped through one protrusion 112b formed in the magnetic core 110. [

The base member 140 and 240 may be provided with a pair of connection terminals 150 and 250 connected to both ends of the coil 120 to supply power supplied from the outside to the coil 120.

Accordingly, when the low-frequency antenna modules 100 and 200 according to the present invention are mounted on a circuit board (not shown), the connection terminals 150 and 250 formed on the base members 140 and 240 are electrically connected to the circuit board, May be supplied to the coil 120 through the circuit board and the connection terminals 150 and 250. [ Here, on one side of the circuit board, connection terminals (not shown) corresponding to the connection terminals 150 and 250 may be formed.

The base member 140 may be a known circuit board having a pair of connection terminals 150 formed thereon and the pair of connection terminals 150 may be connected to the lead portions 121 of the coils 120 The coil binding hole 152 may protrude outward from the body of the connection terminal 150 so as to be wound (refer to Figs. 1 to 3).

As another example, the base member 240 may be made of an insulating resin, and the pair of connection terminals 250 may be integrated with the insulating resin through an insert molding (see FIGS. 4 to 6) .

For example, the connection terminal 250 may be formed of a conductive member, and the conductive member may include a terminal portion 251 exposed to the outside and a bottom surface of the base member 240 to be directly connected to the circuit board, And a coil binding opening 252 extending from an end of the base member 240 and protruding outward from the base member 240 to wind the lead portion 121 of the coil 120 (refer to FIG. 5).

Accordingly, the surface of the conductive member can be insulated by being embedded in the base member 240 made of an insulator, except for the terminal portion 251 for energization and the coil binding aperture 252.

At this time, the base member 240 may have a shape with a top opened by forming a side wall portion 242 extending upward from the rim of the body 241 having a predetermined area.

Accordingly, when the base member 240 and the magnetic core 110 are coupled to each other, the side wall portion 242 covers the side of the coil 120 disposed in the accommodation space, So that the coil 120 can be protected from the external environment.

Here, when the base member 240 includes the side wall portion 242, the terminal portion 251 of the connection terminal 250 may be exposed to the outside and the bottom surface of the base member 240 The coil binding hole 252 may protrude outwardly from the middle of the height of the side wall part 242.

The sidewall portion 242 includes a lead portion 121 extending from the body of the coil 120 and wound around the coil binding portion 252 by forming a wire arrangement groove 243 extending inwardly on the upper surface thereof. The middle of the length can be accommodated.

The low-frequency antenna modules 100 and 200 according to the present invention may be implemented by a Z-axis antenna module, and may be applied together with an X-axis antenna and a Y-axis antenna in which a coil is wound around a conventional bar- .

In addition, the low-frequency antenna modules 100 and 200 may be applied to a keyless entry system including a low-frequency transmitter and a low-frequency receiver.

For example, the low-frequency antenna modules 100 and 200 may be installed in a smart phone, a portable terminal such as a smart phone, or a key fob built in a wearable device such as a smart watch.

Here, the KEY FOB may include a low frequency (LF) receiver including a low frequency antenna module 100, 200, a 3D active immobilizer, and a microcontroller.

Accordingly, low frequency (LF) communication in the 22 kHz band is performed between the key fob mounted on the smart key 10 and the control unit mounted on the vehicle, for example, to wirelessly open the door or steering of the vehicle, At least one of the lock or unlock can be controlled.

In addition, the low-frequency antenna modules 100 and 200 described above can be used as a keyless start system in which a driver can start a vehicle, operate and stop the engine while being electronically authenticated without inserting or manipulating a separate mechanical key, As shown in FIG. It is also noted that the molding type low frequency antenna module 100 may be implemented as a low frequency transmitter constituting a keyless entry system.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100,200: Low frequency antenna module
110: magnetic core 112a, 112b:
120: coil 121: lead part
130: magnetic sheet 130a: insertion hole
131: Adhesive member 132: Protective film
140, 240: base member 142: engaging hole
241: body 242:
243: coil placement groove 150, 250: connection terminal
152: coil coupling portion 251: terminal portion
252:

Claims (16)

Magnetic core;
A coil wound along the circumferential direction of the magnetic core and disposed on a side of the magnetic core;
A pair of magnetic sheets respectively coupled to upper and lower surfaces of the magnetic core so as to cover the upper and lower surfaces of the coil; And
And a base member having a pair of connection terminals to which both ends of the coil are connected. The method according to claim 1,
Wherein the magnetic core has protrusions protruding from a top surface and a bottom surface of the magnetic core, the protrusions protruding from the top surface and the bottom surface, respectively, and insertion holes formed in a region corresponding to the protrusions,
And the protrusion is inserted into the insertion hole when the magnetic core and the magnetic sheet are coupled. The method according to claim 1,
Wherein the magnetic sheet is divided into a plurality of minute pieces. The method according to claim 1,
Wherein the magnetic sheet is a ferrite sheet. The method according to claim 1,
Wherein an adhesive member is disposed on the opposite side of the magnetic sheet and the magnetic core. 3. The method of claim 2,
Wherein the base member is formed with a coupling hole passing through a region corresponding to the protrusion, and the protrusion is inserted into the coupling hole. The method according to claim 1,
And the base member is a circuit board on which the pair of connection terminals are formed. 8. The method of claim 7,
And the connection terminal includes a coil binding hole through which the end of the coil is wound. The method according to claim 1,
Wherein the base member is made of an insulating resin, and the pair of connection terminals are insert molded. 10. The method of claim 9,
Wherein the base member includes a sidewall portion extending upward from the rim at a predetermined height, and the sidewall portion covers a side portion of the coil to prevent the sidewall portion from being exposed to the outside. 11. The method of claim 10,
Wherein the pair of connection terminals are formed to protrude outward from the sidewall portion and include a coil binding hole through which the end of the coil is wound. 12. The method of claim 11,
Wherein the side wall part is formed with a wire arrangement groove that is drawn inward on an upper surface thereof, and a lead part extending from a body of the coil and wound around the coil binding hole is disposed. A smart key having the molding type low frequency antenna module according to any one of claims 1 to 12. A portable terminal incorporating the molding low-frequency antenna module according to any one of claims 1 to 12. A wearable device incorporating the molding type low frequency antenna module according to any one of claims 1 to 12. receiving set; And a transmitter, the keyless entry system comprising:
A keyless entry system in which the low-frequency antenna module according to any one of claims 1 to 12 is incorporated in the receiver.

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