JP2016023490A - Antenna unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability and reliability of an antenna unit which is bent in conformity with the shape of a door handle of a vehicle.SOLUTION: An antenna unit 1A has at least an antenna 10, a detection electrode 20, and a circuit board 30 stored and held in an inner space formed of a case 40 made of flexible resin and a lid 50. The antenna 10 and circuit board 30 are arranged across a gap along a lengthwise direction of a door handle, the detection electrode 20 is arranged over from the side of the antenna 10 to the side of the circuit board 30, and a connection part 23 of the detection electrode 20 is soldered to the circuit board 30. The detection electrode 20 is provided with an elastic deformation part 22 at a part corresponding to the gap between the antenna 10 and circuit board 30.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an antenna unit including a capacitance sensor, for example, an antenna unit incorporated in a door handle of a vehicle adopting a passive entry system.

  Patent Document 1 describes an antenna unit incorporated in a door handle of a vehicle that employs a passive entry system. An antenna unit described in Patent Literature 1 includes an unlock electrode and a lock electrode for detecting a capacitance that changes when a user touches a door handle, an antenna for communicating with a user's portable device, and a lock electrode. And a resin that integrally covers the antenna, and a circuit board that outputs a detection signal corresponding to detection of a change in capacitance by the unlock electrode or the lock electrode.

  In the antenna unit described in Patent Document 1, the circuit board and the antenna are arranged in a direction corresponding to the longitudinal direction of the door handle, and the unlock electrode is arranged in parallel with the direction in which the circuit board and the antenna are arranged. ing. The resin covering the antenna unit has a bent portion at a position between the circuit board and the antenna in a direction corresponding to the longitudinal direction of the door handle, and is bent around the position of the bent portion. ing. Further, the unlock electrode is formed of a thin metal plate having a plasticity that can maintain the shape of the resin covering the antenna unit in a folded state.

  According to the antenna unit described in Patent Document 1, the antenna unit can be bent according to the shape of the door handle, and the same antenna unit can be used for door handles having different shapes.

  On the other hand, in Patent Document 2, a storage base in which a plurality of storage portions are connected by elastically deformable thin plate-like connecting portions, and a low-frequency antenna, a capacitance sensor electrode plate, and a circuit board are distributed to the plurality of storage portions. A door handle device is described in which a low-frequency antenna, a capacitance sensor electrode plate, and a circuit board are integrally arranged by positioning the storage base in the internal space of the handle body.

According to the door handle device described in Patent Document 2, since the storage base can be bent in accordance with the shape of the handle body, there is a degree of freedom in the design of the handle body, and a curved design is possible.

JP 2010-213082 A JP 2007-191917 A

In the antenna unit described in Patent Document 1, the unlock electrode is made of a metal plate having plasticity, and the metal plate is plastically deformed when bent according to the shape of the door handle. Have
That is, the curved portion of the metal plate (unlock electrode) is in a stress state exceeding the yield point (elastic limit), and if the bending angle needs to be finely adjusted, the bending operation will be repeated multiple times. Constriction and cracks are likely to occur in the curved portion. For this reason, when mounted on a vehicle and repeatedly subjected to vibration, there is a possibility that the metal plate may be broken due to insufficient strength of the curved portion, and there is a problem that durability is likely to be lowered.
In addition, once the antenna unit is bent, it is extremely difficult to return the metal plate (unlock electrode) to its original state without distortion. If the bending angle is corrected after bending, the detection characteristics will change. It has the problem of being easy.

Further, in the door handle device described in Patent Document 2, although the storage base can be bent in accordance with the shape of the handle body, the low-frequency antenna, the capacitance sensor electrode plate, the circuit board, Is simply described as connecting the low-frequency antenna and the capacitance sensor electrode plate to a predetermined terminal of the circuit board, and no countermeasure is taken against bending.
Therefore, when the storage base is bent to match the shape of the handle body, a large force may be applied to the terminal connection part of the capacitive sensor electrode plate and the entire circuit board, possibly damaging the terminal connection part and the circuit board. There is.

  Therefore, the present invention is intended to prevent the deterioration of the durability of the capacitance sensor electrode (detection electrode) of the antenna unit that is bent in accordance with the shape of the door handle and to prevent variation in detection characteristics, and to connect the terminals of the capacitance sensor electrode. It is an object of the present invention to provide an antenna unit that can prevent damage to a part and a circuit board.

  Hereinafter, the aspect of this invention made | formed in order to solve said subject is described. In addition, the component employ | adopted in each aspect as described below can be employ | adopted as arbitrary combinations as possible. In addition, aspects or technical features of the present invention are not limited to those described below, but are described in the whole specification and drawings, or invented by the person skilled in the art from those descriptions. It is recognized on the basis of.

  A first aspect of the present invention relating to an antenna unit disposed in an interior space of a door handle detects an antenna for communicating with a user's portable device and a capacitance that changes when the user touches the door handle. A circuit board having a detection electrode for output, a detection circuit that outputs a detection signal corresponding to a change in the capacitance detected by the detection electrode, the antenna, the detection electrode, and the circuit board; A resin case for holding the antenna, the antenna and the circuit board are arranged with a gap along the longitudinal direction of the door handle, and the detection electrode is disposed from the antenna side to the circuit board side. One end is solder-connected to the circuit board, and the detection electrode is provided with an elastic deformation portion at a portion corresponding to the gap.

  The second aspect of the present invention is characterized in that the case has a first thin portion at a portion corresponding to the gap.

  According to a third aspect of the present invention, there is provided a resin lid that covers the opening surface of the case, and the lid has a second thin portion at a portion corresponding to the gap.

  The fourth aspect of the present invention is characterized in that the elastically deforming portion is formed in a U-shaped curve in a direction perpendicular to the substrate surface of the circuit board.

According to the antenna unit of the present invention, it is possible to effectively prevent a large force from being applied to the solder connection portion of the detection electrode and the circuit board when the antenna unit is bent in accordance with the shape of the door handle, and the bending angle. Even if this correction is repeated, the detection characteristics of the detection electrode do not change greatly. As a result, a highly durable and reliable antenna unit can be realized.

1 is an exploded perspective view of an antenna unit according to a first exemplary embodiment of the present invention. The antenna unit which concerns on the 1st Example of this invention is shown, (a) is a top view, (b) is a top view in the state which removed the cover, (c) is the sectional view on the AA line of (a). (D) is sectional drawing at the time of bending an antenna unit according to the shape of a door handle. It is a disassembled perspective view of the antenna unit which concerns on the 2nd Example of this invention. The antenna unit which concerns on the 2nd Example of this invention is shown, (a) is a top view, (b) is a top view in the state which removed the cover, (c) is BB sectional drawing of (a). (D) is sectional drawing at the time of bending an antenna unit according to the shape of a door handle.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
1 and 2 show an antenna unit according to a first embodiment of the present invention.
The antenna unit 1A of this example is incorporated in a door handle of a vehicle that employs a so-called smart entry system in which a door lock device is controlled by performing predetermined communication with a portable device carried by a user.

The antenna unit 1A of this example is fixed at a predetermined position in the internal space of the door handle, and mainly includes an antenna 10, a detection electrode 20, a circuit board 30, a case 40, and a lid 50.

  The case 40 is a resin container having a predetermined flexibility so that the antenna 10, the detection electrode 20, and the circuit board 30 can be arranged along the longitudinal direction of a door handle (not shown). It is elongated in a substantially rectangular parallelepiped shape. The case 40 is composed of four peripheral walls 41 and a bottom wall 42.

  On the peripheral wall 41 of the case 40, first thin portions 44a and 44b are provided at predetermined positions in the longitudinal direction (left and right direction in FIG. 2). The first thin portions 44a and 44b are formed to be thin so that they can be bent more easily than other portions. In this example, the first thin portions 44a and 44b are formed to have a thickness that is about ½ of the other portions.

The bottom wall 42 of the case 40 is a portion that is arranged along the surface on the back side (that is, the vehicle body side) of the door handle, and covers the bottom portion of the peripheral wall 41. Further, the bottom wall 42 has a flange 43 protruding in four directions from the peripheral wall 41.

  The lid 50 closes the opening surface of the case 40 and is made of a resin having a predetermined flexibility. The lid 50 is constituted by four outer peripheral walls 51 and a top wall 52, and is formed in a substantially rectangular parallelepiped shape like the case 40.

  The outer peripheral wall 51 of the lid 50 is provided with second thin portions 53a and 53b at portions corresponding to the first thin portions 44a and 44b of the case 40. The second thin portions 53a and 53b are formed to be thin so that they can be bent more easily than other portions, and in this example, the second thin portions 53a and 53b are formed to have a thickness that is about ½ of the other portions. The lid 50 is assembled to the case 40 so as to close the opening surface of the case 40 with the outer peripheral wall 51 placed on the flange 43, and is fixed to the case 40 by adhesion or the like.

The antenna 10 communicates with a portable device carried by a user of the vehicle to transmit / receive an ID signal or the like. In this example, the antenna 10 is configured by winding a coil around an elongated rod-shaped ferrite core. The antenna 10 can be molded with resin as necessary.
The antenna 10 is fixed at a predetermined position in the internal space of the case 40. Specifically, the antenna 10 is arranged on one side in the longitudinal direction of the case 40 (in this example, more than the first thin portions 44a and 44b in FIG. 2) so as not to overlap the first thin portions 44a and 44b of the case 40. Arranged on the left side) and fixed. The method of fixing the antenna 10 in the case 40 is not particularly limited, and any method such as fitting, press-fitting, locking, and adhesion can be employed.

The detection electrode 20 detects a capacitance that changes when the user touches the door handle, and is configured by a press-formed product of a conductive metal plate.
The material of the detection electrode 20 is not particularly limited, but a copper alloy having excellent spring characteristics and high fatigue strength such as beryllium copper and phosphor bronze (Cu—Sn—P alloy) is suitable.

The detection electrode 20 has a detection part 21 and a connection part 23, and an elastic deformation part 22 is formed between the detection part 21 and the connection part 23, and is fixed at a predetermined position in the internal space of the case 40. The method for fixing the detection electrode 20 in the case 40 is not particularly limited, and any method such as fitting, press-fitting, locking, and adhesion can be employed.

The detection part 21 of the detection electrode 20 is a sensor part formed in a flat plate shape, and is arranged in a part corresponding to a region where the user touches the door handle. Specifically, the detection unit 21 is disposed in close contact with the bottom wall 42 of the case 40, and does not overlap the first thin-walled portions 44 a and 44 b of the case 40. In the example, it is arranged on the left side of the first thin portions 44a and 44b in FIG. In addition, the detection part 21 and the antenna 10 are distribute | arranged via the predetermined gap | interval in the up-down direction of FIG.2 (c) so that it may not contact mutually.

The elastic deformation portion 22 of the detection electrode 20 is disposed in a portion corresponding to the first thin portions 44 a and 44 b in the longitudinal direction of the case 40. The elastic deformation portion 22 is formed in a form that is more easily elastically deformed than other portions, and in this example, the elastic deformation portion 22 is bent in an inverted U shape from the bottom wall 42 side of the case 40 to the top wall 52 side of the lid 50. And formed in a direction perpendicular to the substrate surface of the circuit board 30.

The connection part 23 of the detection electrode 20 is soldered to a predetermined pattern part formed on the circuit board 30. The connecting portion 23 is on the other side in the longitudinal direction of the case 40 (in this example, on the right side of the first thin portions 44a and 44b in FIG. 2) so as not to overlap the first thin portions 44a and 44b of the case 40. It is arranged.

The circuit board 30 has a detection circuit (not shown) that outputs a detection signal corresponding to a change in capacitance detected by the detection electrode 20. The circuit board 30 is on the other side in the longitudinal direction of the case 40 (in this example, on the right side of the first thin portions 44a and 44b in FIG. 2) so as not to overlap the first thin portions 44a and 44b of the case 40. , And is arranged substantially parallel to the bottom wall 42.
A slit-like connection hole 31 is formed in the circuit board 30. Then, the connection portion 23 of the detection electrode 20 is inserted into the connection hole 31 from the bottom wall 42 side and crimped, and then soldered on the top wall 52 side, so that the detection electrode 20 is electrically connected to the detection circuit of the circuit board 30. Connected.

As described above, the antenna 10, the detection electrode 20, and the circuit board 30 are accommodated and held in the case 40, the connection portion 23 of the detection electrode 20 is soldered to a predetermined pattern of the circuit board 30, and then the lid 50 is attached to the case 40. Assemble. Thereafter, a soft resin such as a thermosetting soft resin, a thermoplastic soft resin, or rubber is filled into the case 40 from an injection hole (not shown) provided in the case 40 or the lid 50 as necessary. A plurality of harnesses (not shown) extending from the antenna 10 and the circuit board 30 are led out of the case 40 and connected to a control unit on the vehicle side.

The antenna unit 1A of the present example configured as described above is incorporated into a door handle of a vehicle door. Specifically, the case 40 is incorporated in the door handle so that the bottom wall 42 of the case 40 is on the door side.
Then, when the user holding the portable device puts his hand into the gap formed between the door handle and the door handle to open the door, the capacitance of the detection electrode 20 changes, and this change occurs. Is detected by a detection circuit provided on the circuit board 30 and a detection signal is output.
When the detection signal is output, the control unit of the vehicle transmits a request signal from the antenna 10, and the portable device that has received the request signal transmits its own ID signal.
And the control part of the vehicle which received the ID signal is in a state where the door can be opened by unlocking the door lock device of the vehicle when the received ID signal matches the ID stored in advance. Become.

Although only the detection electrode 20 for unlocking the door lock device is provided in the antenna unit 1A of this example, a lock detection electrode for locking the door lock device may be separately provided. A push switch can be provided separately instead of. When the lock detection electrode is integrated and incorporated in the antenna unit, for example, it is formed as a circuit pattern on the circuit board 30 or disposed at a predetermined position using a press-formed product of a conductive metal plate. Can be.
Similar to the detection electrode 20, such a lock detection electrode detects that the user has touched a predetermined position of the door handle based on a change in capacitance, and locks the door lock device based on the detection result. Configured as follows.

In general, a door handle attached to a door of a vehicle is often configured in a curved shape, and the antenna of the antenna unit is configured using a ferrite core or the like, so that the degree of freedom in shape is low. Further, since a rigid board on which various circuit components are mounted is used as the circuit board, the degree of freedom in shape is also low. In addition, the detection electrode for unlocking the door needs to detect the change in capacitance due to the user's hand touching the curved surface of the door handle facing the door of the vehicle. It is necessary to make the shape along.
On the other hand, when the antenna unit is bent in accordance with the shape of the door handle, a large force is easily applied to the solder connection portion of the detection electrode and the circuit board, and there is a risk of damage to the solder connection portion and the circuit board.

Therefore, in the antenna unit 1A of the present example, first, the antenna 10 and the detection electrode are formed in the internal space formed by the resin case 40 and the lid 50 that are flexible enough to be bent according to the shape of the door handle. 20 and the circuit board 30 are accommodated and held.
The antenna 10 and the circuit board 30 are arranged along the longitudinal direction of the door handle via a gap, and the detection electrode 20 is provided with an elastic deformation portion 22 at a portion corresponding to the gap.

According to the antenna unit 1A of the present example configured as described above, as shown in FIG. 2 (d), it can be easily bent at the gap portion between the antenna 10 and the circuit board 30, and can be easily formed into a door handle shape. Can be matched. Thereby, the distance between the detection part 21 of the detection electrode 20 arranged in close contact with the bottom wall 42 of the case 40 and the back surface of the door handle can be kept substantially constant, and the capacitance of the detection electrode 20 changes. Can be detected stably, and the operability is improved.
Although the detection electrode 20 is disposed across the antenna 10 side from the circuit board side 30, the elastic deformation portion 22 is provided in a portion corresponding to the gap between the antenna 10 and the circuit board 30, so that the antenna unit is bent. In this case, it is possible to effectively prevent a large force from being applied to the connection portion 23 and the circuit board 30. In addition, even if the bending angle is corrected several times, the elastic deformation portion 22 does not plastically deform, and the detection characteristics of the detection electrode 20 do not change greatly. As a result, a highly durable and reliable antenna unit is realized.

Further, in the antenna unit 1 </ b> A of this example, the case 40 is provided with first thin portions 44 a and 44 b at portions corresponding to the gap between the antenna 10 and the circuit board 30. For this reason, it can be easily and reliably bent at the gap portion between the antenna 10 and the circuit board 30, and it is possible to reliably prevent an unintended bending stress from being applied to the antenna 10 and the circuit board 30 during the bending.

In addition, the antenna unit 1A of the present example includes a resin lid 50 that covers the opening surface of the case 40, and the lid 50 includes a second thin portion 53a and a portion corresponding to the gap between the antenna 10 and the circuit board 30. 53b is provided. For this reason, it can prevent more reliably that the bending stress which is not intended to apply to the antenna 10 or the circuit board 30 is applied when bending, ensuring waterproofness.

Furthermore, in the antenna unit 1A of the present example, the elastically deforming portion 22 of the detection electrode 20 is formed in a U-shaped curve in a direction perpendicular to the surface to be bent (the bottom wall surface of the case 40), and is a circuit board. It is curved in a U-shape in a direction perpendicular to the 30 substrate surfaces. For this reason, it can prevent very effectively that big force is added to the connection part 23 or the circuit board 30 when bending.

(Second Embodiment)
3 and 4 show an antenna unit according to a second embodiment of the present invention.
In FIG. 3 and FIG. 4, the same reference numerals as those in FIG. 1 and FIG.

In the first embodiment, the first thin portion is provided only on the peripheral wall 41 of the case 40, but in this example, the first thin portion 44 c is also provided on the bottom wall 42 of the case 40.
In the first embodiment, the second thin portion is provided only on the outer peripheral wall 51 of the lid 50. However, in this example, the second thin portion 53c is also provided on the top wall 52 of the lid 50.

In the first embodiment, only one detection electrode is provided, but in this example, two detection electrodes 20A and 20B are provided. The connection portions 23A and 23B of the detection electrodes 20A and 20B are inserted into the connection holes 31A and 31B of the circuit board 30 from the bottom wall 42 side and soldered on the top wall 52 side, and the detection electrodes 20A and 20B are connected to the circuit. It is electrically connected to the detection circuit of the substrate 30.

Also in the antenna unit 1B of the present example, the antenna 10 and the detection electrodes 20A and 20B are formed in an internal space formed by the resin case 40 and the lid 50 having such flexibility that can be bent according to the shape of the door handle. The circuit board 30 is accommodated and held. Further, the antenna 10 and the circuit board 30 are arranged along the longitudinal direction of the door handle via a gap, and the detection electrodes 20A and 20B are provided with elastic deformation portions 22A and 22B at portions corresponding to the gap.

According to the antenna unit 1B of the present example configured as described above, similarly to the antenna unit 1A of the first embodiment, the antenna unit 1B can be easily folded at the gap portion between the antenna 10 and the circuit board 30, and can be easily handled by the door handle. The antenna unit can be adapted to the shape of the antenna and has high durability and reliability.

In addition, since the antenna unit 1B of this example has a plurality of detection electrodes, by detecting the user's contact from the detection results of these detection electrodes 20A and 20B, the influence of noise is eliminated and the detection accuracy is improved. Can do. Specifically, for example, a user's contact can be detected by detecting a difference value or a ratio between output signals of two detection electrodes or comparing a ratio between an output signal of two detection electrodes and a threshold value. .

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it is needless to say that the above embodiments can be appropriately modified without departing from the spirit of the present invention. Yes.
For example, the elastic deformation part of the detection electrode is not limited to the U shape, and any form can be adopted, and any form can be adopted for the first thin part of the case and the second thin part of the lid. It is.

1A, 1B Antenna unit 10 Antenna 20, 20A, 20B Detection electrode 21, 21A, 21B Detection part 22, 22A, 22B Elastic deformation part 23, 23A, 23B Connection part 30 Circuit board 31, 31A, 31B Connection hole 40 Case 41 Perimeter wall 42 bottom wall 43 鍔 44a, 44b, 44c first thin part 50 lid 51 outer peripheral wall 52 top wall 53a, 53b, 53c second thin part

Claims (4)

An antenna unit arranged in the interior space of the door handle,
An antenna for communicating with the user's mobile device;
A detection electrode for detecting a capacitance that changes when the user touches the door handle;
A circuit board having a detection circuit that outputs a detection signal corresponding to a change in the capacitance detected by the detection electrode;
The antenna, the detection electrode, and the circuit board are accommodated, and a resin case that holds them is provided,
The antenna and the circuit board are arranged through a gap along the longitudinal direction of the door handle,
The detection electrode is arranged over the circuit board side from the antenna side, one end is solder-connected to the circuit board,
The detection electrode is provided with an elastic deformation portion at a portion corresponding to the gap.
An antenna unit characterized by that. The antenna unit according to claim 1, wherein the case has a first thin portion at a portion corresponding to the gap. A resin lid covering the opening surface of the case;
The antenna unit according to claim 2, wherein the lid has a second thin portion at a portion corresponding to the gap. 4. The antenna unit according to claim 1, wherein the elastically deforming portion is formed to be bent in a U shape in a direction perpendicular to a substrate surface of the circuit board. 5.

Images