JP2019100152A - Proximity sensor and keyless entry device including the same - Google Patents

Abstract

To provide a proximity sensor in which the degree of freedom of design is enhanced.SOLUTION: A proximity sensor 1 includes a circuit board 2, one surface of which is printed with a detection circuit 22, and a locking electrode 3 and an unlocking electrode 4, one ends of which are connected electrically to the detection circuit 22. A drive electrode 3A and a reception electrode 3B of the locking electrode 3 are configured in forms of wire harnesses 3a and 3b, and these wire harnesses 3a and 3b are made to extend from the circuit board 2. The extending ends of the wire harnesses 3a and 3b separate from the detection circuit 2 are configured as a detection part. Electrode plates 9 constituting the detection part may be connected to the free ends of the wire harnesses 3a and 3b. The free ends of the wire harnesses 3a and 3b or the electrode plates 9 may be integrated using resin moldings 8 and 10, respectively.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a proximity sensor incorporated in a door handle of a vehicle and a keyless entry device including the same.

  In recent years, in order to enhance the convenience of opening and closing operations of a vehicle door, a driver carrying an electronic key incorporating a portable transmitter for transmitting a code signal locks or unlocks the door of the vehicle only by approaching / separating the vehicle ( A keyless entry device in which locking and unlocking are performed has been developed and has already been put to practical use (see, for example, Patent Document 1).

  A door handle device of a vehicle adopting such a keyless entry device is provided with an antenna that transmits and receives code signals and the like, and a proximity sensor that detects that the driver approaches or contacts the door handle based on a change in capacitance. It is done. Then, when the driver carrying the electronic key touches the door handle to open the door, the proximity sensor built in the door handle detects it and requests from the vehicle authentication device to the electronic key via the antenna. A signal is sent. Then, the electronic key receiving the request signal transmits its own code signal to the vehicle authentication device, and the vehicle authentication device receiving the code signal is unique to the received code signal stored in advance. If it agrees with the code signal, it is determined that the authentication is OK, and the actuator of the door lock device is driven to bring the door into an unlockable (unlocked) state.

  Also, when the driver gets out of the vehicle and touches the door handle to close the door, the proximity sensor similarly detects it, and the code signal received by the electronic key matches the code signal unique to the vehicle In this case, the authentication is OK, and the actuator of the door lock device is driven to lock the door.

  By the way, the proximity sensor used in the keyless entry device proposed in Patent Document 1 includes a lock electrode and an unlock electrode which are formed of a pair of metal plates arranged in parallel on the circuit board. .

JP, 2016-070052, A

  However, in the proximity sensor proposed in Patent Document 1, since it is necessary to arrange a pair of metal plates constituting the lock electrode side by side on the circuit board, the layout restriction due to the diversification of the design of the door handle There is a problem that the shape and processing of the metal plate are complicated and the proximity sensor can not follow the design of the door handle.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a proximity sensor with a high degree of freedom in design and a keyless entry device including the proximity sensor.

In order to achieve the above object, the invention according to claim 1 is
A circuit board on which a detection circuit is printed on one side,
A detection electrode electrically connected at one end to the detection circuit;
In the proximity sensor provided with
The detection electrode is extended from the circuit board, and an extended end of the detection electrode which is separated from the circuit board is configured as a detection unit.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, the detection electrode is constituted by a wire harness in which a metal wire is covered by a resin cover.

  The invention according to claim 3 is characterized in that, in the invention according to claim 2, an electrode plate constituting the detection unit is connected to a free end of the wire harness.

The invention according to claim 4 is the invention according to claim 2.
The detection electrode is composed of a drive electrode and a reception electrode in which an electric field is generated between the drive electrode,
The free end portion of the drive electrode and the reception electrode formed by the wire harness may be integrated by resin molding.

  In the invention according to claim 5, in the invention according to claim 3, the electrode plate of the drive electrode connected to the free end of the wire harness and the electrode plate of the reception electrode are integrally covered with a resin mold It is characterized by

The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein a longitudinally extending case for housing the circuit board is provided.
The detection electrode may be bent and extended from one surface of the circuit board, and the side surface in the short direction of the case may be a detection surface.

The invention according to claim 7 is the invention according to any one of claims 1 to 6,
The case is composed of a door handle disposed on a vehicle door,
A handle case provided with a recess for receiving the circuit board;
A handle cover closing the recess of the handle case;
Equipped with
The extended tip portion of the detection electrode is fixed to either the handle case or the handle cover.

The invention according to claim 8 is
A proximity sensor built into the vehicle's door handle;
An antenna for transmitting and receiving signals between the proximity sensor and a portable transmitter;
An actuator for locking or unlocking the door of the vehicle;
The antenna detects that the code signal received from the portable transmitter matches the code signal unique to the vehicle, and detects the ON / OFF of the proximity sensor by the output of the proximity sensor, and the proximity sensor A controller that drives the actuator to lock or unlock the door when it is turned on;
In the keyless entry device provided with
The proximity sensor is configured of the proximity sensor according to any one of claims 1 to 7, and the controller turns on the proximity sensor when the output reduction amount of the proximity sensor exceeds a predetermined threshold. It is characterized in that it is determined.

  According to the first aspect of the present invention, the detection electrode is extended from the circuit board, and the extended end of the detection electrode which is removed from the circuit board is configured as the detection unit. Therefore, it is necessary to configure the detection unit on the circuit board And the degree of freedom in the design of the proximity sensor is enhanced.

  According to the second aspect of the present invention, since the detection electrode is configured by the wire harness, the detection portion can be provided outside the circuit board with a simple configuration.

  According to the invention of claim 3, since the electrode plate as the detection unit is connected to the free end of the wire harness constituting the detection electrode, a wider detection surface is secured as compared with the case where the detection electrode is constituted only by the wire harness. The detection accuracy of the detection electrode can be enhanced.

  According to the fourth and fifth aspects of the invention, since the drive electrode (electrode plate) composed of the wire harness and the free end (electrode plate) of the reception electrode are covered and integrated with a resin mold, the drive electrode and the reception are integrated. The water resistance of the electrode is enhanced. In addition, since the distance between the drive electrode and the reception electrode is kept constant, the variation in detection accuracy can be reduced.

  According to the invention of claim 6, by utilizing the side surface in the short direction of the case in which the circuit board is accommodated as the detection surface, the structure of the proximity sensor can be simplified.

  According to the seventh aspect of the present invention, the extension end (or the electrode plate connected to the extension end) of the detection electrode (wire harness) is fixed to the handle case or handle cover constituting the door handle. Damage to the detection electrode due to Further, in connection between the wire harness and the electrode plate, the wire harness such as a lead wire may be attached to the electrode plate by welding, ultrasonic welding, soldering or the like, so even if it is difficult to fix the wire harness alone , The end of the wire harness can be fixed. In addition, as a connection method of a wire harness and an electrode plate, you may make it insert mold an electrode plate in a handle case or a handle cover, and make it connect to a wire harness.

  According to the eighth aspect of the present invention, by using a proximity sensor with a high degree of freedom in design for the keyless entry device, the design of the door handle incorporating the proximity sensor is enhanced.

1 is a perspective view of a proximity sensor according to Embodiment 1 of the present invention. It is a back view of a proximity sensor concerning Embodiment 1 of the present invention. It is a perspective view of the handle case in which the proximity sensor concerning Embodiment 1 of the present invention was incorporated. It is the partial perspective view which looked at the handle cover which shows the modification of Embodiment 1 of this invention from diagonally inside. It is a perspective view of the proximity sensor which concerns on Embodiment 2 of this invention. It is a back view of the proximity sensor concerning Embodiment 2 of the present invention. It is a perspective view of the handle case where the proximity sensor concerning Embodiment 2 of the present invention was incorporated. It is the partial perspective view which looked at the handle cover which shows the modification of Embodiment 2 of this invention from diagonally inside. It is a perspective view which shows the state before resin-molding the electrode plate of the proximity sensor which concerns on Embodiment 3 of this invention. It is a perspective view of the proximity sensor which concerns on Embodiment 3 of this invention. It is a back view of the proximity sensor concerning Embodiment 3 of the present invention. It is a perspective view of the handle case in which the proximity sensor concerning Embodiment 3 of the present invention was incorporated. It is the fragmentary perspective view which looked at the handlebar cover which shows the modification of Embodiment 3 of this invention from diagonally inside. It is a block diagram showing the system configuration of the keyless entry device concerning the present invention. It is an electric circuit diagram of the keyless entry device concerning the present invention. It is a flow chart which shows the processing procedure of the keyless entry device concerning the present invention.

  Hereinafter, an embodiment of a proximity switch according to the present invention will be described based on the attached drawings.

[Proximity switch]
Embodiment 1
1 is a perspective view of a proximity sensor according to a first embodiment of the present invention, FIG. 2 is a back view of the proximity sensor, and FIG. 3 is a perspective view of a handle case incorporating the proximity sensor. The proximity sensor 1 according to the present invention generates an electric field between the electrodes by mutual capacitance method to detect the proximity or contact of the user's hand such as a driver, and the keyless entry device 20 (see FIG. 14) described later. It is used.

  Thus, as shown in FIGS. 1 and 2, the proximity sensor 1 according to the present embodiment is an elongated rectangular circuit in which the detection circuit 22 (see FIG. 15) is printed on one surface (front or back). A combination of a substrate 2, a lock electrode 3 (see FIG. 1) and an unlock electrode 4 (see FIG. 2) which are detection electrodes whose one end is electrically connected to the detection circuit 22, and an antenna 5 and a shield electrode 6 They are integrated and integrated by resin molding.

  The lock electrode 3 includes a drive electrode 3A and a reception electrode 3B extended from one end in the longitudinal direction of the surface of the circuit board 2 as shown in FIG. 1, and these drive electrode 3A and the reception electrode 3B are It is comprised by wire harness 3a, 3b, respectively. Here, the wire harnesses 3a and 3b are configured by covering metal wires 3a1 and 3b1 such as copper wires with resin covers 3a2 and 3b2 having high electrical insulation. The extended ends (free ends) of the wire harnesses 3a and 3b constituting the drive electrode 3A of the lock electrode 3 and the reception electrode 3B, which are separated from the circuit board 2, respectively constitute a detection unit. The shield electrode 6 is disposed at the center in the longitudinal direction of the surface of the circuit board 2.

  Further, as shown in FIG. 2, the unlocking electrode 4 is composed of a driving electrode 4A and a receiving electrode 4B which are disposed parallel to each other in the longitudinal direction at one end of the back surface of the circuit board 2. The driving electrode 4A and the receiving electrode 4B are formed as a thin and substantially rectangular metal plate by press forming of a highly conductive copper plate or the like.

  Furthermore, the antenna 5 is configured by winding a coil 5b around a bobbin 5a formed in a tubular shape by a resin, and inserting and fixing a ferrite (not shown) inside the bobbin 5a.

  Thus, the proximity sensor 1 integrated by the resin mold as described above is incorporated into the inside of the handle case 11 of the door handle of the vehicle, as shown in FIG. Here, the handle case 11 is integrally formed of resin in a U-shape, and on the outer surface (upper surface in FIG. 3), a concave portion 11a opening toward the vehicle outer side (upper in FIG. 2) is longitudinal It is formed along the The proximity sensor 1 according to the present invention is incorporated in the recess 11 a of the handle case 11. In this case, the wire harnesses 3a and 3b constituting the drive electrode 3A and the reception electrode 3B of the lock electrode 3 are bent and extended from the circuit board 2 (see FIGS. 1 and 2). The handle case 11 is pulled out through a rectangular notch 11 b formed at the rear end (right end in FIG. 3) of the handle case 11. And the extended end (free end) which comprises the detection part of these wire harness 3a, 3b is being fixed to the side of the handle case 11. As shown in FIG. Therefore, the side surface (rear end surface) of the handle case 11 in the short direction is used as a detection surface. In addition, the connection part with the circuit board 2 (refer FIG.1 and FIG.2) of two wire harness 3a, 3b is sealed with the circuit board 2 by the low voltage | pressure resin mold 7. FIG.

  By the way, from the front end (left end in FIG. 3) and the rear end (right end in FIG. 3) of the steering wheel case 11, the arm 11A and the operating portion 11B are projected substantially at right angles toward the vehicle inside (lower side in FIG. 3) A notched circular shaft hole 11c is formed at the tip of the arm 11A having an L shape. A pivot formed at the front end of a handle base (not shown) is fitted in the shaft hole 11c, and the handle case 11 is supported rotatably around the pivot.

  Further, an engagement recess 11d is formed in the actuating portion 11B projecting from the rear end portion of the handle case 11, and a handle lever (not shown) is engaged with the engagement recess 11d. . The handle lever operates a door lock mechanism (not shown) incorporated in the vehicle body. When the handle case 11 is rotated about a support shaft (not shown), the actuating portion 11B of the handle case 11 is operated. The handle lever also moves in the same direction along with the movement of the door, whereby the door lock mechanism (not shown) is activated to open the door lock.

  In the proximity sensor 1 according to the present invention, as a method of fixing the two wire harnesses 3a and 3b, a method of sandwiching the wire harnesses 3a and 3b by the handle case 11 and the handle cover 12 (see FIG. 4) covering the same. A method of sandwiching by a cover member (not shown) as a separate member other than the handle cover 12 and the handle case 11, a method of providing a claw-like member on a resin mold and engaging the claw-like member with the handle case 11 or the handle cover 12; A method of bonding or welding the wire harnesses 3a and 3b can be considered.

  Here, a modified example of the present embodiment is shown in FIG. 4, but as shown in the figure, the extended ends of the two wire harnesses 3a and 3b which are incorporated in the handle cover 12 and derived therefrom The (free end) may be fixed inside the handle cover 12. FIG. 4 is a partial perspective view of the handle cover 12 as viewed obliquely from the inside.

  According to the proximity sensor 1 according to the present embodiment, the drive electrode 3A and the reception electrode 3B of the lock electrode 3 are configured by the wire harnesses 3a and 3b, and the wire harnesses 3a and 3b are separated from the circuit board 2 The extension (free end) of the wire harnesses 3a and 3b out of the circuit board 2 is configured as a detection unit, so that there is no need to configure the detection unit on the circuit board 2, and the configuration is simple. The detection unit can be provided outside the circuit board 2, and the effect of being able to increase the degree of freedom in the design of the proximity sensor 1 can be obtained. Further, in the present embodiment, since the drive electrode 3A and the reception electrode 3B of the lock electrode 3 are configured by the wire harnesses 3a and 3b, the detection unit can be provided outside the circuit board 2 with a simple configuration. Moreover, it is possible to follow various designs only by changing the lengths of the wire harnesses 3a and 3b, and the versatility is excellent. Furthermore, since the wire harnesses 3a and 3b can be arranged along the handle design, the distance between the touch surface that brings the hand close or in contact with the touch and the electrodes 3A and 3B can be reduced.

  Further, in the proximity sensor 1 according to the present embodiment, the structure of the proximity sensor 1 can be simplified because the side surface in the short direction of the handle case 11 in which the circuit board 2 is accommodated is used as a detection surface. The effect of being able to

  Furthermore, in the present embodiment, since the extended ends (free ends) of the wire harnesses 3a and 3b are fixed along the handle design surface to the handle case 11 or the handle cover 12 constituting the door handle, The effect of being able to prevent damage to harness 3a, 3b is also acquired.

Second Embodiment
Next, a second embodiment of the proximity sensor according to the present invention will be described.

  5 is a perspective view of a proximity sensor according to a second embodiment of the present invention, FIG. 6 is a back view of the proximity sensor, and FIG. 7 is a perspective view of a handle case incorporating the proximity sensor. The same reference numerals as in FIG. 1 to FIG. 3 denote the same elements in FIG.

  In proximity sensor 1 ′ according to the present embodiment, extended ends (free ends) of wire harnesses 3a and 3b constituting drive electrode 3A of lock electrode 3 and reception electrode 3B are integrated by resin mold 8 The other configuration is the same as that of the proximity sensor 1 according to the first embodiment.

  Thus, according to the proximity sensor 1 'according to the present embodiment, the extended ends (free ends) of the wire harnesses 3a and 3b are covered with the resin mold 8 to be integrated. The water resistance of 3b is enhanced. Further, since the distance between the two wire harnesses 3a and 3b is kept constant, the effect of suppressing the variation in the detection accuracy of the proximity sensor 1 'can be obtained. Further, as in the first embodiment, there is no need to form a detection unit on the circuit board 2, and the detection unit can be provided outside the circuit board 2 with a simple configuration. The effect of being able to increase the degree of freedom is also obtained.

  Here, a modified example of the present embodiment is shown in FIG. 8, but as shown in the figure, extension of two wire harnesses 3a and 3b to be built in the proximity sensor 1 'in the handle cover 12 and derived therefrom The ends (free ends) may be integrated by the resin mold 8. FIG. 8 is a partial perspective view of the handle cover 12 as viewed obliquely from the inside.

Embodiment 3
Next, a third embodiment of the proximity sensor according to the present invention will be described.

  FIG. 9 is a perspective view showing a state before resin-molding an electrode plate of a proximity sensor according to Embodiment 3 of the present invention, FIG. 10 is a perspective view of the same proximity sensor, and FIG. 12 is a perspective view of a handle case in which the same proximity sensor is incorporated, and in these figures, the same elements as those shown in FIGS. Description of is omitted.

  In the proximity sensor 1 ′ ′ according to the present embodiment, as shown in FIG. 9, the extended end portions (free end portions) of the wire harnesses 3 a and 3 b constituting the drive electrode 3 A of the lock electrode 3 and the reception electrode 3 B. The electrode plate 9 constituting the detection unit is connected to each other, and as shown in FIGS. 10 to 12, the electrode plate 9 is covered and integrated with a resin mold 10, and the other configuration is The configuration is the same as that of the proximity sensor 1 according to the first embodiment.

  By the way, in the connection between the wire harnesses 3a and 3b and the electrode plate 9, the wire harnesses 3a and 3b may be attached to the electrode plate 9 by welding, ultrasonic welding, soldering or the like. Even if it is difficult to fix, the ends of the wire harnesses 3a and 3b can be fixed. As a method of connecting the wire harnesses 3a and 3b and the electrode plate 9, the electrode plate 9 is insert molded in the handle case 11 or the handle cover 12 (see FIG. 13) and connected to the wire harnesses 3a and 3b. Also good.

  Thus, according to the proximity sensor 1 ′ ′ according to the present embodiment, the electrode plates 9 as a detection unit are respectively provided at the free ends of the wire harnesses 3 a and 3 b constituting the drive electrode 3 A and the reception electrode 3 B of the lock electrode 3. Since the connection is made, a wider detection surface can be secured as compared with the case of the first embodiment in which the detection electrodes are constituted only by the wire harnesses 3a and 3b, and the detection accuracy of the lock electrode 3 can be enhanced. Since the electrode plates 9 respectively connected to the extending end portions (free end portions) of 3a and 3b are covered and integrated by the resin mold 10, the wire harness is similar to the proximity sensor 1 'according to the second embodiment. The water resistance of 3a, 3b is enhanced.

  In addition, since the distance between the two wire harnesses 3a and 3b is kept constant, an effect of suppressing variation in detection accuracy of the proximity sensor 1 can be obtained. In addition, as in the first embodiment, there is no need to form a detection unit on the circuit board 2, and the detection unit can be provided outside the circuit board 2 with a simple configuration. The effect of being able to increase the degree of freedom is also obtained.

  Here, a modified example of the present embodiment is shown in FIG. 13, but as shown in the figure, extension of two wire harnesses 3a and 3b to be built in the proximity sensor 1 ′ ′ in the handle cover 12 and derived therefrom The electrode plates 9 (see FIG. 9) respectively connected to the ends (free ends) may be integrated by the resin mold 10. Incidentally, FIG. 13 is a partial perspective view of the handle cover 12 as viewed obliquely from the inside.

  As a method of detecting the proximity sensors 1, 1 ', 1' 'according to the first to third embodiments described above, drive electrodes 3A, 4A and receiving electrodes 3B, 4B constituting the lock electrode 3 and the unlock electrode 4, respectively. Although the mutual capacitance system is employed, a self-capacitance system may be employed in which the lock electrode 3 and the unlock electrode 4 are each formed of a single electrode plate.

[Keyless entry device]
Next, an embodiment of a keyless entry device according to the present invention will be described below based on the attached drawings.

  FIG. 14 is a block diagram showing a system configuration of the keyless entry device according to the present invention, and FIG. 15 is an electric circuit diagram of the keyless entry device.

  In the keyless entry device 20 according to the present embodiment, the driver carries the electronic key 21 (see FIG. 14), which is a portable transmitter, and brings his hand close to or touches the door handle of the vehicle. It is intended to automatically lock or unlock the door of the vehicle. In the keyless entry device 20 according to the present embodiment, the proximity sensor 1 (see FIGS. 1 and 2) according to the first embodiment is used.

  Thus, as shown in FIG. 14, the keyless entry device 20 according to the present embodiment includes the proximity sensor 1 incorporated in the handle case, and the proximity sensor 1 connected to the door handle of the driver's hand. The antenna 5 that transmits and receives signals to and from the electronic key 21 when proximity or touch is detected, the detection circuit 22 (see FIG. 15), and an actuator 23 such as a latch device that locks or unlocks the door of the vehicle. The controller 24 detects the on / off of the proximity sensor 1 by the output of the proximity sensor 1 and controls the drive of the actuator 23. The controller 24 is connected to a DC power supply Vcc.

  Here, as shown in FIG. 15, the proximity sensor 1 is provided with a lock electrode 3 and an unlock electrode 4 as detection electrodes, and the lock electrode 3 is configured by wire harnesses 3a and 3b (see FIG. 1). The driving electrode 3A and the receiving electrode 3B are provided. Further, the unlocking electrode 4 includes a driving electrode 4A and a receiving electrode 4B which are formed of a metal plate (see FIG. 2). The detection circuit 22 printed on the circuit board 2 (see FIGS. 1 and 2) is an operational amplifier 25 provided in the path connecting the reception electrode 3B of the lock electrode 3 and the controller 24 as shown in FIG. And an operational amplifier 27 and a diode 28 provided in a path connecting the receiving electrode 4 B of the unlock electrode 4 and the controller 24. A capacitor C1 for charging and a resistor R1 for discharging are provided in a path connecting the receiving electrode 3B of the lock electrode 3 and the controller 24. The receiving electrode 4B of the unlocking electrode 4 and the controller 24 are provided. A capacitor C2 for charging and a resistor R2 for discharging are provided in the path to be connected.

  The controller 24 has a function of applying a pulse voltage to the drive electrode 3A of the lock electrode 3 of the proximity sensor 1 and a drive electrode 4A of the unlock electrode 4 and a function of detecting ON / OFF of the proximity sensor 1. And the function of detecting the ON state of the proximity sensor 1 and transmitting a request signal from the antenna 5 to the electronic key 21 and the response from the electronic key 21 to the antenna 5 in response to the request signal transmitted from the antenna 5 It has a function to check the code signal and a code signal specific to the vehicle, and a function to drive and control the actuator 23 to lock or unlock the door of the vehicle when both code signals match. ing. Although not shown, the controller 24 incorporates an oscillator that generates a pulse voltage, a timer that measures the oscillation time of the oscillator, a memory that stores the measured voltage value, and the like.

  Next, the operation procedure of the keyless entry device 20 according to the present embodiment will be described below based on FIG.

  FIG. 16 is a flow chart showing the processing procedure of the keyless entry device 20. First, when the keyless entry device 20 is operated, the controller 24 drives the drive electrode 3A of the lock electrode 3 of the proximity sensor 1 and the drive electrode 4A of the unlock electrode 4 On the other hand, a pulse voltage of a predetermined frequency (for example, 125 kHz) is applied (step S1 in FIG. 16).

  Then, an electric field is generated between the drive electrode 3A and the reception electrode 3B of the lock electrode 3 and between the drive electrode 4A and the reception electrode 4B of the unlock electrode 4, respectively, and from the drive electrode 3A of the lock electrode 3 to the reception electrode 3B. As a result, electric lines of force are generated from the drive electrode 4A of the unlock electrode 4 toward the receiving electrode 4B. Therefore, voltages are induced in the reception electrode 3 B of the lock electrode 3 and the reception electrode 4 B of the unlock electrode 4. Then, the voltages induced in the reception electrodes 3B and 4B are amplified by the operational amplifiers 25 and 27 of the detection circuit 22 to charge the capacitors C1 and C2 (step S2). The application of the pulse voltage to the drive electrodes 3A and 4A may be simultaneously performed to both drive electrodes 3A and 4A, or may be separately performed according to the situation.

  Thus, for example, when the driver opens the door in a locked state to get in the vehicle at rest, the driver inserts the hand into the door handle, and the driver inserts it into the door handle. A part of electric lines of force generated from the drive electrode 4A of the unlock electrode 4 provided on the proximity sensor 1 toward the reception electrode 4B is absorbed by the driver's hand which is a dielectric. As a result, the number of generated electric lines of force decreases, the voltage induced in the receiving electrode 4B decreases, and the charge (voltage) charged in the capacitor C2 also decreases.

  On the other hand, when the driver gets out of the vehicle, closes the door, and approaches or touches the door handle to bring the door in the unlocked state into a locked state, proximity is obtained. A part of electric lines of force generated from the drive electrode 3A of the lock electrode 3 provided in the sensor 1 toward the reception electrode 3B is absorbed by the hand of the driver who is a dielectric. As a result, the number of generated electric lines of force decreases, the voltage induced in the receiving electrode 3B decreases, and the charge (voltage) charged in the capacitor C1 also decreases.

  The application of the pulse voltage and the charging of the capacitors C1 and C2 are performed only for a predetermined time set in advance. That is, the controller 24 determines whether or not the time measured by a timer (not shown) incorporated therein has exceeded a predetermined time (step S3), and if the predetermined time has not elapsed (step S3: No) The above process (oscillation and charging) is repeated, and application of the pulse voltage is stopped (step S4) when a predetermined time has elapsed (step S3: Yes).

  Thereafter, the voltage values of the charged capacitors C1 and C2 are measured (step S5), and the measured voltage values are stored in a memory (not shown) (step S6). Then, it is determined whether the potential difference ΔV between the voltage value measured this time and the voltage value measured last time exceeds a predetermined threshold A (step S7). When the driver's hand approaches or contacts the door handle, the amount of charge charged to the capacitors C1 and C2 decreases as described above, so the voltage values of the capacitors C1 and C2 to be measured are measured last time It becomes lower than the voltage value.

  As described above, when the potential difference ΔV between the voltage value measured this time and the voltage value measured last time is compared with the predetermined threshold A (step S7), the charge stored in the capacitors C1 and C2 is When the controller 24 reads a voltage value, it is discharged by the resistors R1 and R2 (steps S8 and S15).

  As a result of the determination in step S7, when the potential difference ΔV between the voltage value measured this time and the voltage value measured last time exceeds the predetermined threshold A (ΔV> A) (step S7: Yes) Is determined that the proximity sensor is turned on (step S9). As described above, when it is determined that the proximity sensor 1 is turned on, the controller 24 transmits a request signal to the electronic key 21 carried by the driver (step S10). Then, the electronic key 21 receiving this request signal sends a code signal back to the antenna 5 (step S11).

  Then, the controller 24 collates the code signal returned from the electronic key 21 with the code signal unique to the vehicle, and determines whether or not both match (step S12). As a result of this determination, when the code signal returned from the electronic key 21 matches the code signal unique to the vehicle (step S12: Yes), the actuator 23 is controlled to drive and lock the door or unlock the door. Lock (unlock) (step S13).

  Specifically, when the driver's hand approaches or contacts the front surface side of the door handle, the voltage value of the capacitor C1 on the lock side decreases. Therefore, the controller 24 determines that the driver uses the door for locking, and drives the actuator 23 to lock the door in the unlocked state. In addition, when the driver's hand is inserted into the inside of the door handle, the voltage of the capacitor C2 on the unlock side decreases. Therefore, the controller 24 determines that the driver is about to unlock the door, and drives the actuator 23 to unlock the door in the locked state.

  As described above, when the actuator 23 is controlled to drive and the door is locked (locked) or unlocked (unlocked), a series of processing is ended, and thereafter, the same processing as described above is repeated (step S14).

  On the other hand, as a result of the determination in step S7, when the potential difference ΔV between the voltage value measured this time and the voltage value measured last time is less than or equal to the predetermined threshold A (ΔV ≦ A) (step S7: No), The charge stored in the capacitors C1 and C2 is discharged by the resistors R1 and R2 when the controller 24 reads the voltage value (step S15), and it is determined that the proximity sensor 1 is in the OFF state (step S16). ). If, as a result of the determination in step S12, the code signal sent back from the electronic key 21 does not match the code signal unique to the vehicle (step S12: No), the process is terminated as it is, and so forth. Are repeated (step S14).

  As described above, according to the keyless entry device 20 according to the present embodiment, since the proximity sensor 1 with a high degree of freedom in design is used, the effect of improving the design of the door handle in which the proximity sensor 1 is incorporated is enhanced. can get.

1,1 ', 1 "proximity sensor 2 circuit board 3 lock electrode 3A drive electrode of lock electrode 3B lock electrode reception electrode 3a, 3b wire harness 3a1, 3b1 wire harness metal wire 3a2, 3b2 wire harness resin cover 4 ann Lock electrode 4A Unlock electrode drive electrode 4B Unlock electrode reception electrode 5 Antenna 5a Antenna bobbin 5b Antenna coil 6 Shield electrode 7 Low voltage resin mold 8 Resin mold 9 Electrode plate 10 Resin mold 11 Handle case 11A Handle case arm 11B Handle case operating portion 11a Handle case recessed portion 11b Handle case cutaway portion 11c Handle case shaft hole 11d Operating portion engaged recess 12 Handle cover 20 Keyless entry device 21 Electronic key (for portable use Transmitter)
22 detection circuit 23 actuator 24 controller 25, 27 operational amplifier 26, 28 diode C1, C2 capacitor R1, R2 resistance

Claims (8)

A circuit board on which a detection circuit is printed on one side,
A detection electrode electrically connected at one end to the detection circuit;
In the proximity sensor provided with
The proximity sensor characterized in that the detection electrode is extended from the circuit board, and an extended end of the detection electrode which is separated from the circuit board is configured as a detection unit.   The proximity sensor according to claim 1, wherein the detection electrode is configured by a wire harness in which a metal wire is covered by a resin cover.   The proximity sensor according to claim 2, wherein an electrode plate constituting the detection unit is connected to a free end of the wire harness. The detection electrode is composed of a drive electrode and a reception electrode in which an electric field is generated between the drive electrode,
3. The proximity sensor according to claim 2, wherein the drive electrode made of the wire harness and the free end of the reception electrode are integrated by resin molding.   4. The proximity sensor according to claim 3, wherein the electrode plate of the drive electrode connected to the free end of the wire harness and the electrode plate of the reception electrode are covered and integrated with a resin mold. Providing a longitudinally extending case for receiving the circuit board;
The proximity sensor according to any one of claims 1 to 5, wherein the detection electrode is bent and extended from one surface of the circuit board, and the side surface in the short direction of the case is used as a detection surface. . The case is composed of a door handle disposed on a vehicle door,
A handle case provided with a recess for receiving the circuit board;
A handle cover closing the recess of the handle case;
Equipped with
The proximity sensor according to any one of claims 1 to 6, wherein the extended tip portion of the detection electrode is fixed to any one of the handle case and the handle cover. A proximity sensor built into the vehicle's door handle;
An antenna for transmitting and receiving signals between the proximity sensor and a portable transmitter;
An actuator for locking or unlocking the door of the vehicle;
The antenna detects that the code signal received from the portable transmitter matches the code signal unique to the vehicle, and detects the ON / OFF of the proximity sensor by the output of the proximity sensor, and the proximity sensor A controller that drives the actuator to lock or unlock the door when it is turned on;
In the keyless entry device provided with
The proximity sensor is configured of the proximity sensor according to any one of claims 1 to 7, and the controller turns on the proximity sensor when the output reduction amount of the proximity sensor exceeds a predetermined threshold. A keyless entry device characterized in that it is determined.

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