WO2017199952A1 - Buckle, vehicle-mounted system, and seatbelt system - Google Patents

Abstract

Provided is a buckle comprising: a main body that can be connected to a tongue attached to a seatbelt of a vehicle; a buckle switch that detects whether the tongue and the main body are connected; and an occupant sensor that detects an occupant in the seat of the vehicle. The occupant sensor switches the function of detection of the occupant using the detection state of the buckle switch. Also provided are: a vehicle-mounted system comprising the buckle and a receiving device that receives the information detected by the occupant sensor; and a seatbelt system comprising the buckle.

Description

Buckle, in-vehicle system and seat belt system

The present invention relates to a buckle, an in-vehicle system, and a seat belt system.

2. Description of the Related Art Conventionally, a buckle is known that includes a buckle switch that detects connection with a tongue attached to a seat belt of a vehicle and an occupant sensor that detects the presence or absence of an occupant on a seat by infrared rays (for example, Patent Document 1 reference). Based on the detection result of the buckle switch, it is possible to determine whether or not the tongue is connected, and based on the detection result of the occupant sensor, it is possible to determine whether there is an occupant on the seat.

Also, a buckle equipped with a sensor that detects the breathing state of an occupant on a vehicle seat with infrared rays is known (see, for example, Patent Document 2).

Thus, there is a technique for detecting physiological information such as the presence / absence information of an occupant and the breathing state of the occupant as occupant information.

JP 2000-219102 A JP 2013-216187 A

The occupant detection function required for the occupant sensor for detecting the occupant may differ depending on whether the seat belt is worn or not. However, with the above-described conventional buckle, it is difficult to use different types of occupant detection functions depending on the situation where the seat belt is worn or not.

Accordingly, one aspect of the present invention provides a buckle, an in-vehicle system, and a seat belt system that can operate different types of occupant detection functions depending on whether the seat belt is attached or not. With the goal.

In order to achieve the above object, in the first aspect of the present invention,
A body portion connectable with a tongue attached to a vehicle seat belt;
A buckle switch for detecting the presence or absence of connection between the tongue and the main body;
An occupant sensor for detecting an occupant on a seat of the vehicle,
The occupant sensor is provided with a buckle that switches the detection function of the occupant using the detection state of the buckle switch.

In order to achieve the above object, in the second aspect of the present invention,
An in-vehicle system is provided that includes the buckle and a receiving device that receives detection information from the occupant sensor.

In order to achieve the above object, in the third aspect of the present invention,
A vehicle seat belt,
A tongue attached to the seat belt;
A buckle connectable with the tongue,
The buckle is
A buckle switch for detecting whether or not the tongue and the buckle are connected;
An occupant sensor for detecting an occupant on a seat of the vehicle,
A seat belt system is provided in which the occupant sensor switches the detection function of the occupant using the detection state of the buckle switch.

According to the above aspect of the present invention, the occupant sensor switches the occupant detection function using the detection state of the buckle switch. Accordingly, the occupant sensor can switch the occupant detection function in accordance with a situation where the tongue and the buckle are connected (that is, a situation where the seat belt is worn). Alternatively, the occupant sensor can switch the occupant detection function according to a situation where the tongue and the buckle are not connected (that is, a situation where the seat belt is not worn). Therefore, different types of occupant detection functions can be activated depending on whether the seat belt is worn or not.

It is a figure which shows an example of a structure of a seatbelt system. It is a figure which shows the passenger | crew sitting on the seat from the viewpoint from upper direction. It is a block diagram which shows an example of a structure of a vehicle-mounted system. It is a side view which shows an example of the main-body part of a buckle. It is a perspective view which shows an example of the main-body part of a buckle. It is a top view which shows an example of the main-body part of a buckle. It is a figure which shows an example of the radiation | emission state of an electromagnetic wave by the side view of a buckle. It is a figure which shows an example of the radiation | emission state of an electromagnetic wave by the top view of a buckle. It is a figure which shows an example of a structure of a sensor. It is a figure which shows an example of a structure of the Doppler sensor which is a specific example of a sensor. It is a figure which shows an example of the relationship between the movement of a detection target object, and a detection output. It is a figure which shows an example of the relationship between the displacement of a passenger | crew's body surface, and a detection output. It is a figure which shows an example of a structure of a buckle switch and a receiver. It is a figure which shows an example of the other structure of a buckle switch and a receiver. It is a figure which shows an example of a structure of the main-body part of a buckle. It is a timing chart which shows an example of the voltage output of a buckle switch, and the voltage output of a crew member sensor. It is a timing chart which shows an example of the current output of a buckle switch, and the current output of a crew member sensor. It is a block diagram which shows another example of a structure of a vehicle-mounted system. It is a figure which shows an example of the other structure of the main-body part of a buckle. It is a timing chart which shows an example of the voltage output of a buckle switch, and the voltage output of a crew member sensor. It is a timing chart which shows an example of the current output of a buckle switch, and the current output of a crew member sensor. It is a timing chart which shows an example of the current output of a buckle switch, and the current output of a crew member sensor. It is a timing chart which shows an example of the voltage output of a buckle switch, and the voltage output of a crew member sensor.

Embodiments according to the present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1 is a diagram illustrating an example of a configuration of a seat belt system 1 according to an embodiment. The seat belt system 1 is an example of a system mounted on a vehicle. The seat belt system 1 includes, for example, a seat belt 4, a retractor 3, a shoulder anchor 6, a tongue 7, and a buckle 8.

The seat belt 4 is an example of a webbing that restrains the occupant 11 sitting on the seat 2 of the vehicle, and is a belt-like member that is wound around the retractor 3 so that it can be pulled out. The belt anchor 5 at the tip of the seat belt 4 is fixed to the floor of the vehicle body or the seat 2.

The retractor 3 is an example of a take-up device that enables the seat belt 4 to be taken up or pulled out, and the seat belt 4 is pulled out from the retractor 3 when a deceleration of a predetermined value or more is applied to the vehicle during a vehicle collision or the like. Limit that. The retractor 3 is fixed to the seat 2 or a vehicle body near the seat 2.

The shoulder anchor 6 is an example of a belt insertion tool through which the seat belt 4 is inserted, and is a member that guides the seat belt 4 pulled out from the retractor 3 toward the shoulder of the occupant.

The tongue 7 is an example of a belt insertion tool through which the seat belt 4 is inserted, and is a component that is slidably attached to the seat belt 4 guided by the shoulder anchor 6.

The buckle 8 is a part to which the tongue 7 is detachably connected, and is fixed to the floor of the vehicle body or the seat 2, for example.

The buckle 8 has a main body 8a and a stay 8b. The main body 8a is a part to which the tongue 7 is detachably connected. The stay 8 b is an example of a support member that supports the main body 8 a of the buckle 8. The stay 8b is fixed to the floor of the vehicle body or the seat 2.

In the state where the tongue 7 is engaged with the buckle 8, the portion of the seat belt 4 between the shoulder anchor 6 and the tongue 7 is a shoulder belt portion 9 that restrains the chest and shoulders of the occupant. In a state where the tongue 7 is engaged with the buckle 8, the portion of the seat belt 4 between the belt anchor 5 and the tongue 7 is a lap belt portion 10 that restrains the occupant's waist.

FIG. 2 is a view showing the occupant 11 sitting on the seat 2 from a viewpoint from above. FIG. 2 shows the backrest of the seat 2.

The breathing of the occupant 11 seated on the seat 2 causes the body surface of the occupant 11 (for example, the surface of the waist, the surface of the abdomen, the surface of the chest, etc.) to be slightly displaced. For example, when the occupant 11 inhales, the body surface of the occupant 11 expands in the vehicle front-rear direction and the vehicle width direction, and when the occupant 11 exhales, the body surface of the occupant 11 contracts in the vehicle front-rear direction and the vehicle width direction. . Therefore, the breathing of the occupant 11 can be detected by detecting the displacement of the body surface of the occupant 11.

The buckle 8 has a sensor 20 provided on the main body 8a as means for detecting the displacement of the body surface of the occupant 11. The sensor 20 may be provided on the stay 8b. The buckle 8 is disposed below the side of the occupant 11 sitting on the seat 2. The sensor 20 is provided on the side portion of the buckle 8 on the occupant 11 side. The sensor 20 may be a means for detecting displacement in the body of the occupant 11.

The sensor 20 is an example of an object detection unit that detects the movement of an object on the vehicle seat 2 in a non-contact manner. The object on the seat 2 is not limited to the occupant 11, and includes objects other than the person such as the occupant 11. The sensor 20 outputs a sensor output signal whose waveform changes according to the movement of the object on the seat 2. The “movement of the object” is not limited to the movement of the surface of the object, and may be movement inside the object.

The sensor 20 detects, for example, the movement of an object on the vehicle seat 2 in a non-contact manner by transmitting and receiving radio waves. The sensor 20 detects a movement of an object on the seat surface by transmitting a radio wave toward the upper side of the seat surface of the seat 2 of the vehicle and receiving a reflected wave with respect to the transmitted radio wave.

Specific examples of radio waves transmitted and received by the sensor 20 include VHF band (Very High Frequency) radio waves, UHF (Ultra-High Frequency) band, SHF (Super High Frequency) band microwaves, and the like. The VHF band represents a frequency band of 30 MHz to 0.3 GHz. The UHF band represents a frequency band of 0.3 GHz to 3 GHz. The SHF band represents a frequency band of 3 G to 30 GHz.

Alternatively, the sensor 20 may be an object detection unit that detects the movement of an object on the vehicle seat 2 in a non-contact manner from a change in capacitance between the object and the sensor electrode of the sensor 20.

FIG. 3 is a block diagram showing an example of the configuration of the in-vehicle system 1A. The in-vehicle system 1A includes a buckle 8 and an ECU 100. The buckle 8 includes a main body 8a, a buckle switch 13, and an occupant sensor 12. ECU stands for Electronic Control Unit.

The main body 8a is a part that can be connected to the tongue 7 (see FIG. 1). In the example shown in FIG. 3, the main body 8 a includes a buckle switch 13 and an occupant sensor 12.

The buckle switch 13 is an example of a connection detection unit that detects the connection between the tongue 7 and the main body 8a. The buckle switch 13 detects whether or not the seat belt 4 is worn by detecting whether or not the tongue 7 and the main body 8a are connected. The buckle switch 13 detects a state in which the tongue 7 and the main body 8a are not connected as a state in which the seat belt 4 is not worn (a state in which the seat belt 4 is not worn). On the other hand, the buckle switch 13 detects a state in which the tongue 7 and the main body 8a are connected as a state in which the seat belt 4 is worn (a state in which the seat belt 4 is worn).

The occupant sensor 12 switches whether to output the presence / absence information of the occupant 11 on the seat 2 or the physiological information of the occupant 11 on the seat 2 using the detection state of the buckle switch 13. The detection state of the buckle switch 13 includes a connection non-detection state in which the buckle switch 13 does not detect the connection between the tongue 7 and the main body portion 8a, and a connection between the tongue 7 and the main body portion 8a. And the connected detection state.

The occupant sensor 12 includes a sensor 20, a presence / absence information detection unit 26, and a physiological information detection unit 27.

The sensor 20 detects the movement of the occupant 11 on the seat 2 and outputs a sensor output signal corresponding to the movement.

The presence / absence information detection unit 26 has a presence / absence information detection function for detecting whether or not the occupant 11 is present based on the sensor output signal output from the sensor 20 and outputting presence / absence information indicating the presence or absence of the occupant 11. Have. The presence / absence information detection unit 26 may have a presence / absence information detection function that outputs remind information that prompts the occupant 11 to attach the seat belt 4 based on the presence / absence information of the occupant 11. The presence / absence information detection function is an example of a passenger detection function.

The physiological information detection unit 27 has a physiological information detection function for detecting and outputting the physiological information of the occupant 11 based on the sensor output signal output from the sensor 20. The physiological information detection function is an example of an occupant detection function.

Physiological information includes vital sign information related to vital signs that are at least one of breathing and pulse. Specific examples of vital sign information relating to respiration include the presence or absence of the current respiration, the current respiration cycle, the average respiration cycle, the spontaneous respiration cycle, the respiration variation, and the respiratory abnormality. Specific examples of vital sign information related to the pulse include the presence / absence of the current pulse, the current pulse period, the average pulse period, pulse variation, and pulse abnormality. The physiological information may include vital sign information related to vital signs such as a consciousness level and body temperature.

The physiological information detection unit 27 has a physiological information detection function that detects at least one vital sign information to detect a state such as yawning or drowsiness of the occupant 11 and outputs the detected result as physiological information. You may have.

The ECU 100 is an example of a receiving device that receives the presence / absence information and physiological information of the occupant 11. The presence / absence information and physiological information of the occupant 11 are both examples of detection information by the occupant sensor 12. The ECU 100 includes one or a plurality of electronic control devices that are separate from the buckle 8. The ECU 100 executes control using presence / absence information and physiological information.

The situation where the ECU 100 needs the presence / absence information of the occupant 11 and the situation where the ECU 100 needs the physiological information of the occupant 11 are not necessarily the same. For example, in the situation where the tongue 7 and the buckle 8 are connected, it can be considered that the occupant 11 is present, and therefore the ECU 100 needs the physiological information of the occupant 11 compared to the presence / absence information of the occupant 11. high. On the other hand, in the situation where the tongue 7 and the buckle 8 are not connected, the ECU 100 determines whether the occupant 11 is not present or the occupant 11 is not wearing the seat belt 4. The necessity of the presence / absence information of the occupant 11 is higher than the above.

Therefore, the occupant sensor 12 of the present embodiment uses the detection state of the buckle switch 13 to switch between the presence / absence information of the occupant 11 and the physiological information of the occupant 11 to output. Accordingly, the occupant sensor 12 can output physiological information of the occupant 11 in a situation where the tongue 7 and the buckle 8 are connected, for example, and in a situation where the tongue 7 and the buckle 8 are not connected, the occupant 11 Can be output. In this way, the occupant sensor 12 can output the presence / absence information and the physiological information by switching depending on the situation where the tongue 7 and the buckle 8 are connected or not connected. Different types of occupant information can be output. That is, the occupant sensor 12 can appropriately output the presence / absence information of the occupant 11 and the physiological information of the occupant 11.

In the example shown in FIG. 3, the main body 8a of the buckle 8 has at least three terminals 14, 15, and 16, and the ECU 100 has at least three terminals 101, 102, and 103. The in-vehicle system 1A includes a wiring 17 that connects the terminal 14 and the terminal 101 to each other, a wiring 18 that connects the terminal 15 and the terminal 102 to each other, and a wiring 19 that connects the terminal 16 and the terminal 103 to each other. Prepare.

FIG. 4 is a side view showing an example of the main body 8 a of the buckle 8. FIG. 5 is a perspective view showing an example of the main body 8 a of the buckle 8. FIG. 6 is a plan view showing an example of the main body 8a of the buckle 8 from the viewpoint from the passenger side. The main body 8 a has an insertion port 8 c into which the metal plate of the tongue 7 is inserted, and a button 8 d for the occupant to perform the detaching operation of the tongue 7.

The sensor 20 is built in the side surface portion of the main body portion 8a on the seat 2 side (occupant side sitting on the seat 2). When the sensor 20 is a sensor that transmits and receives radio waves, the sensor 20 is provided between the shielding plate 21 and the side surface on the sheet 2 side of the main body 8a so that the radio waves are not radiated in unnecessary directions. It is preferable to arrange | position. The shielding plate 21 is built in the main body 8 a and shields radio waves radiated from the sensor 20.

FIG. 7 is a diagram showing an example of a radio wave radiation state in a side view of the buckle 8. FIG. 8 is a diagram illustrating an example of a radio wave radiation state when the buckle 8 is viewed from above.

Radio wave radiation range varies depending on the antenna that transmits and receives radio waves and the frequency of radio waves. The antenna may be mounted on the sensor 20 in a state where the antenna is tilted in the direction in which the occupant is present, or the directivity of the antenna may be controlled in the direction in which the occupant is present.

The radio wave transmitted from the transmitting antenna of the sensor 20 provided on the buckle 8 is reflected by an object on the sheet, and the reflected antenna receives the reflected wave. The sensor 20 changes the standing wave ratio (SWR), the reflected wave reflection intensity, the propagation delay time of the reflected wave with respect to the transmitted wave, the phase change between the transmitted wave and the reflected wave, and transmission. Measure at least one of the frequency changes between the wave and the reflected wave. The sensor 20 can detect a relative position change between the object (detection target) on the sheet 2 and the sensor 20 by measuring at least one of these changes.

Note that these changes such as the standing wave ratio include the distance between the sensor 20 and the detection target, the size of the detection target, the shape of the reflection surface of the detection target, the physical properties of the detection target (for example, a metal plane, Affected by the surface of the human body).

For example, when transmitting and receiving radio waves of 100 MHz to 5 GHz, the sensor 20 measures a change in the standing wave ratio and detects a relative position change with respect to the detection target based on the measurement result. For example, when transmitting and receiving radio waves of 10 GHz to 100 GHz, the sensor 20 measures changes in the standing wave ratio, propagation delay time, and Doppler frequency, and detects changes in relative position with the detection target based on the measurement results. .

When the sensor 20 is an electrostatic sensor that drives the sensor electrode of the sensor 20 at a frequency of, for example, 30 kHz to 1 MHz, the change in capacitance between the detection target and the sensor electrode is measured, and the measurement result Based on this, a change in relative position with the detection object is detected.

In this embodiment, as shown in FIGS. 7 and 8, the radio wave is radiated toward the upper side of the sheet 2 with a spread angle of 40 ° or more and 90 ° or less. If the directivity of the radio wave is narrowed, a relative position change in a narrow range can be detected. Conversely, if the directivity of the radio wave is widened, a relative position change in a wide range can be detected.

In addition, when the detection target is located in the vicinity of the sensor 20, the detection accuracy of the relative position change is strongly influenced by the situation in the vicinity of the sensor 20. Therefore, even if a plurality of sensors other than the sensor 20 are present in the vehicle interior, or even if the directivity of the radio wave slightly deviates from the desired spread angle, the sensor 20 changes in relative position with respect to the detection target. Can be detected with high accuracy.

1 and 2, the side surface of the buckle 8 faces, for example, the waist side surface of the occupant 11 sitting on the seat 2. The radio wave transmitted from the sensor 20 at a predetermined spread angle is reflected by the seat 2 and the abdomen (including the flank) of the occupant 11, and the reflected wave arrives at the sensor 20. Therefore, the sensor 20 detects the relative position change between the buckle 8 and the abdomen (including the flank) in addition to the relative position change between the buckle 8 and the waist.

For example, when the occupant 11 inhales, the flank expands and approaches the sensor 20, and the front part of the stomach protrudes toward the front side of the vehicle, increasing the radio wave reflection area. As a result, the intensity of the reflected wave increases. In particular, when the occupant 11 inhales while wearing the seat belt 4, the chest of the occupant 11 expands, and the tension of the seat belt 4 increases, so the buckle 8 is drawn toward the occupant 11 side. This further increases the intensity of the reflected wave.

Conversely, when the occupant 11 exhales, the flank is squeezed away from the sensor 20, and the front part of the abdomen is squeezed toward the rear of the vehicle to reduce the radio wave reflection area. As a result, the intensity of the reflected wave is reduced. In particular, when the occupant 11 exhales while wearing the seat belt 4, the tension of the seat belt 4 decreases due to the chest of the occupant 11 being deflated, so that the buckle 8 moves away from the occupant 11. Thereby, the intensity of the reflected wave is further reduced.

That is, the breathing motion of the occupant 11 can be grasped as the strength of the reflected wave. By detecting the intensity of the reflected wave and analyzing and capturing the frequency of the signal synchronized with the respiration, the occupant 11 can detect the respiration. Alternatively, when the frequency of the radio wave is included in a frequency band that reacts to blood flow, the pulse of the occupant 11 can be detected.

In this way, breathing can be detected even when the seat belt 4 is not worn. In particular, when the seat belt 4 is worn, the seat belt 4 is displaced according to the displacement of the body surface of the occupant 11, and the seat belt 4 The buckle 8 is displaced via the tongue 7 in accordance with the displacement of. Therefore, it is possible to detect respiration and pulse more stably than the conventional method.

FIG. 9 is a diagram illustrating an example of the configuration of the sensor 20. The sensor 20 includes an oscillating unit 22, an output unit 23, a detecting unit 24, and an antenna 25.

The oscillation unit 22 generates a signal that oscillates at a specific stable frequency. The output unit 23 feeds power to the antenna 25 based on the signal generated by the oscillation unit 22. If the matching of the antenna 25 is good, a radio wave is radiated from the antenna 25 into the space while the reflection loss at the antenna 25 is suppressed. The standing wave ratio (SWR) refers to the ratio of the magnitude of the reflected wave to the magnitude of the traveling wave flowing from the output unit 23 to the antenna 25. If the output is stable, a change in the reflected wave from the detection target appears as a change in SWR. Synchronously with the breathing of the occupant 11, the SWR changes periodically as the buckle 8 moves or the detection object moves.

The detection unit 24 detects a received wave (reflected wave) and converts a change received by a high-frequency radio wave (transmitted wave) into a low-frequency change.

Specific examples of detection by the detection unit 24 include amplitude detection, frequency detection, and phase detection. In the phase detection, the phase of the traveling wave of the output unit 23 is compared with the phase of the received wave including the reflected wave, and an I component having the same phase as the traveling wave and a Q component having a 90 ° phase difference with respect to the traveling wave are obtained. And output as a detection output converted to a low frequency. The detection output is an example of a sensor output signal whose waveform changes according to the movement of the object.

The magnitude of the detection output amplitude is calculated by I ² + Q ² . The effective power of the detection output is calculated by multiplying the voltage by the I component (in-phase component) of the current or by multiplying the current by the I component of the voltage. By calculating the tangent of the I component and the Q component, the phase change of the reflected wave with respect to the traveling wave can be obtained. The detection output includes a periodic vital sign signal component representing a vital sign that is at least one of respiration and pulse and an aperiodic movement signal component representing movement (body movement) of an object.

FIG. 10 is a diagram illustrating an example of a configuration of a Doppler sensor 20 </ b> A that is a specific example of the sensor 20.

The Doppler sensor 20A can detect the displacement of the detection object with higher accuracy from the phase change of the reflected wave with respect to the traveling wave due to the Doppler effect. When the detection object moves, the phase of the reflected wave changes, and the standing wave changes at a beat frequency corresponding to the phase change speed. Therefore, the Doppler sensor 20A can detect the Doppler frequency proportional to the phase change rate of the reflected wave with respect to the traveling wave by performing phase detection of the transmitted wave and the reflected wave. Based on the Doppler frequency, it is possible to derive the relative speed between the Doppler sensor 20A and the detection target. Further, when the Doppler sensor 20A selectively detects the Doppler frequency, vehicle vibration, pulse, and respiration can be easily separated.

The frequency of vehicle vibration is 5 Hz to 20 Hz. Specific examples of vehicle vibrations include vibrations due to vehicle travel and vibrations due to impacts on the vehicle. The frequency of the pulse is 1 Hz to 3 Hz, and the frequency of respiration is 0.5 Hz to 0.2 Hz. The higher the relative speed between the Doppler sensor 20A and the detection object, the higher the Doppler frequency is converted. Vehicle vibration having a large amplitude and a high frequency is converted to a high frequency as a Doppler frequency. Therefore, since the vehicle vibration can be easily removed by the filter, the movement signal component synchronized with the movement (body movement) of the object and the vital sign signal synchronized with the vital sign that is at least one of respiration and pulse. It becomes easy to selectively extract the components.

The Doppler sensor 20A uses the Doppler effect to output a Doppler frequency signal (I output and Q output) corresponding to the frequency difference (Doppler frequency) between the transmitted wave and the reflected wave. The I output and the Q output are voltage signals having a phase difference of 90 ° (π / 2).

The Doppler sensor 20A includes, for example, an oscillator 33, a transmission antenna 31, a reception antenna 32, a delay circuit 35, and mixers 34 and 36. A radio wave (for example, a microwave) is transmitted from the transmission antenna 31 by the oscillation signal of the oscillator 33. The radio wave transmitted from the transmission antenna 31 is reflected by the detection object on the sheet 2, and the reception antenna 32 receives the reflected wave. The delay circuit 35 delays the phase of the received signal of the receiving antenna 32 by 90 ° (π / 2). The mixer 34 receives the oscillation signal from the oscillator 33 and the reception signal from the reception antenna 32 to generate an I output (I component). The mixer 36 receives the oscillation signal of the oscillator 33 and the reception signal of the reception antenna 32 whose phase is delayed by the delay circuit 35, and generates a Q output (Q component).

The transmission antenna 31 and the reception antenna 32 are, for example, planar patch antennas formed in a quadrangular shape. There may be a plurality of transmission antennas 31 and reception antennas 32, respectively.

FIG. 11 is a diagram illustrating an example of the relationship between the movement of the detection target and the detection output. FIG. 11A shows the movement of the detection object. The horizontal axis represents the number of samplings, and the vertical axis represents the amount of phase change of the reflected wave with respect to the traveling wave. FIG. 11B shows the detection output (I output and Q output). The horizontal axis represents the number of samplings, and the vertical axis represents the amplitude of the detection output. Based on the detection output, it is possible to determine a movement signal component synchronized with the movement of the detection target. For example, the MPU 30 (see FIG. 15, details will be described later) demodulates the I output and Q output shown in FIG. 11 (b) and calculates the phase change (rotation) of the reflected wave with respect to the traveling wave, The movement signal component shown in FIG. 11A can be detected.

FIG. 12 is a diagram illustrating an example of the relationship between the displacement of the body surface of the occupant 11 and the detection output. FIG. 12A shows the displacement of the body surface of the occupant 11. FIG. 12B shows the detection output (I output and Q output). The horizontal axis represents the number of samplings, and the vertical axis represents the amplitude of the detection output. Based on the detection output, it is possible to detect the displacement of the body surface of the occupant 11. For example, the MPU 30 (see FIG. 15, details will be described later) demodulates the I output and the Q output shown in FIG. 12B and calculates the phase change (rotation) of the reflected wave with respect to the traveling wave. The displacement of the body surface shown in FIG. 12 (a) can be detected.

FIG. 13 is a diagram illustrating an example of the configuration of the buckle switch 13 and the ECU 100A. The ECU 100A is an example of the ECU 100.

The buckle switch 13 includes a hall sensor 40, a transistor 41, a current source 42, and a resistor 43. The buckle switch 13 notifies the ECU 100A of the detection state of the buckle switch 13 via the two wires 18 and 19. The ECU 100A includes a detection resistor 106 that pulls up the wiring 18 to the DC power source 105 of the power supply voltage VB, and an information reception unit 107 that detects the detection voltage Vs generated at both ends of the detection resistor 106. The power supply voltage VB is, for example, 12V.

The detection voltage Vs is generated when the detection current Ia flows through the detection resistor 106. The detection current Ia flows through a route of the DC power source 105, the detection resistor 106, the wiring 18, the transistor 41, the wiring 19, and the ground 104.

The hall sensor 40 is compared with the case where the tongue 7 and the buckle 8 are connected (when the buckle switch 13 is on) and when the tongue 7 and the buckle 8 are not connected (when the buckle switch 13 is off). Thus, the base current for driving the transistor 41 is increased. For example, the current value of the detection current Ia is 7 mA or less when the buckle switch 13 is off, and is 12 mA or more when the buckle switch 13 is on.

Therefore, the information receiving unit 107 can determine whether the buckle switch 13 is on or off based on the change in the detection voltage Vs due to the change in the detection current Ia. For example, when the buckle switch 13 generates a voltage higher than a predetermined threshold between the terminal 15 and the terminal 16 (that is, the detection voltage Vs having a voltage value lower than the predetermined determination threshold is detected. If it is determined that the buckle switch 13 is off. On the other hand, when the buckle switch 13 generates a voltage lower than the threshold value between the terminal 15 and the terminal 16 (that is, the detection voltage Vs having a voltage value higher than the determination threshold value is detected). ), It is determined that the buckle switch 13 is on.

For example, since the minimum voltage applied to the Hall sensor 40 when the buckle switch 13 is on is designed to be 4 V or more, the power supply voltage of the Hall sensor 40 is supplied from the terminal 15.

FIG. 14 is a diagram illustrating an example of the configuration of the buckle switch 13 and the ECU 100B. The ECU 100B is an example of the ECU 100. Even if the detection resistor is inserted in series with the ground line as shown, the information receiving unit 107 can receive the detection state of the buckle switch 13 as in the case of FIG.

The configuration of the buckle switch 13 is the same as that in FIG. The ECU 100B includes a detection resistor 108 that pulls down the wiring 19 to the ground 104, and an information reception unit 107 that detects a detection voltage Vs generated at both ends of the detection resistor 108. As in the case of FIG. 13, the information receiving unit 107 can determine whether the buckle switch 13 is on or off based on the change in the detection voltage Vs due to the change in the detection current Ia.

FIG. 15 is a diagram showing an example of the configuration of the main body 8a of the buckle 8. As shown in FIG. Terminals 14, 15, and 16 are connected to ECU 100 via wires 17, 18, and 19, respectively (see FIG. 3).

In the case of FIG. 15, the main body 8 a has a buckle switch 13 and an occupant sensor 12. The occupant sensor 12 includes, for example, a sensor 20, an MPU (Micro-Processing Unit) 30, a regulator 29, and input / output circuits (capacitor 37, diodes 38 and 39, resistors 47 and 48, a transistor 46, and the like). The ground 28 of the main body 8 a is connected to the terminal 16.

The sensor 20 and the MPU 30 are driven with a voltage (eg, 2.5 V) that is step-down regulated by the regulator 29. The drive current (current consumption) of the sensor 20 and the MPU 30 is about 5 mA in total.

The presence / absence information detection unit 26 and the physiological information detection unit 27 (see FIG. 3) are realized by the MPU 30. A sensor output signal converted into a low frequency by detection by the sensor 20 is input to the MPU 30.

The MPU 30 (presence / absence information detection unit 26) determines whether or not the occupant 11 exists by executing a predetermined presence / absence determination process on the detection output (an example of the sensor output signal) output from the sensor 20. The MPU 30 outputs presence / absence information indicating whether or not the occupant 11 is present from the terminals 14 and 16 by switching the transistor 46.

The MPU 30 (physiological information detection unit 27) detects the physiological information of the occupant 11 by executing a predetermined physiological information detection process on the detection output output from the sensor 20. The MPU 30 outputs the physiological information of the occupant 11 from the terminals 14 and 16 by switching the transistor 46.

The MPU 30 (physiological information detection unit 27) detects a cycle of a vital sign signal component representing a vital sign that is at least one of respiration and pulse from the detection output output from the sensor 20, for example. The MPU 30 has a function of extracting significant features such as the movement of the detection target object from the input sensor output signal and selectively extracting a periodic change in vital signs of breathing or pulse.

The detection state of the buckle switch 13 is input to the MPU 30 via the resistor 45. The MPU 30 switches between presence / absence information output and physiological information output based on the detection state input via the resistor 45.

Since the presence / absence of the occupant 11 and the physiological state (for example, respiration) differ in the frequency and distance ranges to be detected, the MPU 30 detects the presence / absence of the occupant 11 and the physiological state using separate processing logics. For example, when an occupant gets in and sits on the seat 2, the MPU 30 performs processing such as classification such as whether the detected movement is a human movement or a movement of a non-human movement in order to respond to the rapid movement of the occupant. And seating of the occupant 11 is reliably detected. Since the seating is premised after the on-state of the buckle switch 13 is detected, the MPU 30 switches from the presence / absence determination processing logic to the physiological information detection processing logic.

When there is room in the processing capacity of the MPU 30, the MPU 30 may execute both processing logics in parallel. Since the electronic circuit incorporated in the buckle 8 is small and inexpensive and requires power saving, it is preferable to use a power saving processor. However, a small microprocessor may run out of RAM (Random Access Memory) for intermediate processing.

Therefore, the MPU 30 changes the determination threshold according to the difference in switch information (detection state) of the buckle switch 13 and commonly uses the arithmetic processing part. Alternatively, the MPU 30 uses the RAM redundantly by switching the arithmetic processing logic itself according to the difference in the switch information (detection state) of the buckle switch 13. As described above, by switching the internal processing of the MPU 30, it is possible to reduce the necessary resources of the processor, so that a great economic advantage can be obtained in the case of commercialization.

The buckle 8 may include a light emitting diode 44 which is an example of a light emitting unit. For example, the light emitting diode 44 is provided in the main body portion 8 a so as to be visible to the occupant 11.

The MPU 30 changes the light emission mode of the light emitting diode 44 according to the difference in the detection state of the buckle switch 13, for example. The MPU 30 can make the occupant 11 easily recognize the position of the buckle 8 or prompt the occupant 11 to attach the seat belt 4 by turning on the light emitting diode 44 when the buckle switch 13 is off.

The MPU 30 changes the light emission mode of the light emitting diode 44 according to changes in physiological information, for example. The MPU 30 blinks the light emitting diode 44 in synchronization with the detected respiration cycle. As a result, the breathing state of the occupant 11 can be recognized by the blinking of light.

FIG. 16 is a timing chart showing an example of the voltage output of the buckle switch 13 and the voltage output of the occupant sensor 12. FIG. 16 shows an example of operation waveforms of the configuration shown in FIG. In FIG. 16, after the occupant sensor 12 detects a change from the absence of the occupant to the presence and the buckle switch 13 detects the switching from the buckle off to the buckle on, An example of switching to output of respiratory cycle information is shown.

The buckle off indicates that the buckle switch 13 is off, and the buckle on indicates that the buckle switch 13 is on.

When the tongue 7 and the buckle 8 are not connected, the transistor 41 is off (the buckle switch 13 is off). Since the transistor 41 is turned off, the output voltage at both ends of the buckle switch 13 (the voltage between the terminal 15 and the terminal 16) is higher than the threshold Th1. The buckle switch 13 outputs a voltage higher than the threshold value Th <b> 1 from the terminals 15 and 16 as a signal indicating an unconnected state in which the tongue 7 and the buckle 8 are not connected.

The MPU 30 executes the presence / absence determination of the occupant 11 when a voltage higher than the threshold Th1 is detected via the resistor 45.

When the presence of the occupant 11 is not detected, the MPU 30 always turns off the transistor 46, thereby increasing the output voltage (the voltage between the terminal 14 and the terminal 16) at both ends of the occupant sensor 12 above the threshold Th2. . The occupant sensor 12 outputs a voltage higher than the threshold Th <b> 2 from the terminals 14 and 16 as absence information of the occupant 11.

When the occupant gets into the vehicle when the buckle switch 13 is off and the presence of the occupant 11 is not detected, the MPU 30 detects the presence of the occupant 11. When the presence of the occupant 11 is detected, the MPU 30 turns on / off the transistor 46 to output a first period pulse voltage that repeatedly crosses the threshold Th2. The occupant sensor 12 outputs the pulse voltage of the first cycle from the terminals 14 and 16 as the presence information of the occupant 11.

When the tongue 7 and the buckle 8 are connected, the transistor 41 is turned on (the buckle switch 13 is turned on). When the transistor 41 is turned on, the output voltage across the buckle switch 13 is lower than the threshold Th1. The buckle switch 13 outputs a voltage lower than the threshold value Th <b> 1 from the terminals 15 and 16 as a signal indicating a connection state in which the tongue 7 and the buckle 8 are connected.

The MPU 30 detects the physiological information of the occupant 11 when a voltage lower than the threshold Th1 is detected via the resistor 45.

When the voltage lower than the threshold value Th1 is detected via the resistor 45, the MPU 30 regards the occupant 11 as wearing the seat belt 4 and detects physiological information such as a respiratory cycle. When it is detected that the buckle switch 13 is on, the MPU 30 turns on / off the transistor 46 to output a second period pulse voltage that repeatedly crosses the threshold Th2. The occupant sensor 12 outputs the pulse voltage of the second period from the terminals 14 and 16 as physiological information of the occupant 11.

The second cycle is different from the first cycle. In the illustrated example, the second period is longer than the first period, but may be shorter than the first period. Alternatively, the MPU 30 may change the second cycle in proportion to the cycle such as breathing or pulse, or may output a code pulse representing a stable state or unstable state such as breathing or pulse.

FIG. 17 is a timing chart showing an example of the current output of the buckle switch 13 and the current output of the occupant sensor 12. FIG. 17 shows an example of operation waveforms of the configuration shown in FIG. 15 as in the case of FIG. In FIG. 17, as in the case of FIG. 16, the occupant sensor 12 detects a change from the absence of the occupant to the presence, and the buckle switch 13 detects the change from the buckle off to the buckle on. An example of switching from the output of presence information to the output of occupant breathing cycle information will be shown.

When the buckle switch 13 is off, the output current i-Hole (the current flowing through the resistor 43) of the buckle switch 13 is lower than the threshold Th3. The buckle switch 13 outputs an output current i-Hole having a level lower than the threshold Th3 from the terminal 15 as a signal indicating a non-connected state where the tongue 7 and the buckle 8 are not connected.

When the output current i-Hole having a level lower than the threshold Th3 is detected through the resistor 45, the MPU 30 performs the presence / absence determination of the occupant 11.

The MPU 30 reduces the output current i-Out (current flowing through the resistor 47) of the occupant sensor 12 by always turning off the transistor 46 when the presence of the occupant 11 is not detected. The occupant sensor 12 outputs an output current (sum of i-Out and i-Sense) at a level lower than the threshold value Th4 from the terminal 14 as non-existence information of the occupant 11. i-Sense is a power supply current supplied to the regulator 29.

If the occupant gets in when the buckle switch 13 is off and the presence of the occupant 11 is not detected, the MPU 30 detects the presence of the occupant 11. When the presence of the occupant 11 is detected, the MPU 30 turns on / off the transistor 46 to output a third period pulse current that repeatedly crosses the threshold Th4. The occupant sensor 12 outputs the pulse current of the third period from the terminal 14 as the presence information of the occupant 11.

When the buckle switch 13 is on, the output current i-Hole of the buckle switch 13 is higher than the threshold Th3. The buckle switch 13 outputs an output current i-Hole having a level higher than the threshold Th3 from the terminal 15 as a signal indicating a connection state in which the tongue 7 and the buckle 8 are connected.

When the output current i-Hole having a level higher than the threshold Th3 is detected via the resistor 45, the MPU 30 detects the physiological information of the occupant 11.

When the output current i-Hole having a level higher than the threshold value Th3 is detected via the resistor 45, the MPU 30 regards the occupant 11 as wearing the seat belt 4 and detects physiological information such as a respiratory cycle. When the buckle switch 13 is detected to be on, the MPU 30 turns on / off the transistor 46 to output a pulse current having a fourth period that repeatedly crosses the threshold Th4. The occupant sensor 12 outputs a pulse current of the fourth period from the terminal 14 as physiological information of the occupant 11.

The fourth cycle is different from the third cycle. In the illustrated example, the fourth period is longer than the third period, but may be shorter than the third period. Alternatively, the MPU 30 may change the fourth cycle in proportion to the cycle such as breathing or pulse, or may output a code pulse representing a stable state or unstable state such as breathing or pulse.

Thus, in the first embodiment, the occupant sensor 12 switches the presence / absence information and the physiological information according to the switching of the detection state of the buckle switch 13, as shown in FIGS. To do. Thereby, the output of presence information and physiological information can be switched in synchronization with the switching timing of the buckle 8 and the tongue 7 from the coupling to the non-coupling or the switching timing from the non-coupling to the coupling.

In the first embodiment, the occupant sensor 12 outputs physiological information when the buckle switch 13 does not detect the connection between the buckle 8 and the tongue 7 as shown in FIGS. Output presence / absence information. On the other hand, when the buckle switch 13 detects the connection, the occupant sensor 12 outputs physiological information without outputting presence / absence information. Thus, the ECU 100 can easily determine that the information supplied from the occupant sensor 12 is presence / absence information when the buckle switch 13 is detected to be off, and the occupant sensor 12 when the buckle switch 13 is detected to be on. Can be easily determined as physiological information.

Further, in FIG. 16 or FIG. 17, the occupant sensor 12 may switch from the output of the presence information to the output of the physiological information after a predetermined time has elapsed after detecting the switching of the buckle switch 13 from OFF to ON. In addition, in FIG. 16 or FIG. 17, the occupant sensor 12 may switch from outputting physiological information to outputting presence / absence information after a predetermined time has elapsed after detecting switching of the buckle switch 13 from on to off.

23, the occupant sensor 12 outputs the non-existence information of the occupant 11 when the presence of the occupant 11 is not detected and the connection between the buckle 8 and the tongue 7 is not detected by the buckle switch 13. . On the other hand, the occupant sensor 12 outputs physiological information of the occupant 11 when the presence of the occupant 11 is detected and the connection is not detected by the buckle switch 13. Alternatively, the occupant sensor 12 may output remind information that prompts the user to wear the seat belt 4 when the presence of the occupant 11 is detected and the connection is not detected by the buckle switch 13.

For example, as shown in FIG. 23, when the presence of the occupant 11 is detected and a state in which the connection is not detected by the buckle switch 13 has elapsed for a predetermined time, the occupant sensor 12 determines the physiology of the occupant 11 from the output of the presence / absence information of the occupant 11. Switch to output information. Thereby, even if the connection of the buckle 8 and the tongue 7 is not detected by the buckle switch 13 while the output of the presence information of the occupant 11 is continued, the ECU 100 can start receiving physiological information.

Alternatively, the occupant sensor 12 detects the presence of the occupant 11 and the remind information that prompts the user to attach the seat belt 4 from the output of the presence / absence information of the occupant 11 when a state where the connection is not detected by the buckle switch 13 has elapsed. You may switch to the output.

Further, in FIG. 23, the occupant sensor 12 may output the presence information of the occupant 11 as remind information for urging the user to wear the seat belt 4.

Also, for example, when the presence information is detected by the occupant sensor 12 with the buckle switch 13 in the off state, the ECU 100 turns on the air conditioner and the seat heater. This is effective in saving energy.

For example, the ECU 100 can output a belt remind alarm when the wearing of the seat belt 4 is not detected by the buckle switch 13 within a predetermined time after the presence information by the occupant sensor 12 is detected.

For example, the ECU 100 can display the vital sign information of the occupant 11 on the display based on the physiological information supplied from the occupant sensor 12. The ECU 100 may display the vital sign information itself on the display, but may display information obtained based on the vital sign information (for example, information that prompts the occupant 11 to take a break) on the display. Specifically, the ECU 100 may display information prompting the occupant 11 to take a break (for example, information reminiscent of a break such as a coffee cup) when the occurrence frequency of yawning or drowsiness exceeds a predetermined level. Good.

Further, in the first embodiment, the buckle 8 includes terminals 14 and 16 as output terminals shared for outputting presence / absence information and physiological information (see, for example, FIG. 3). As a result, the number of wires connecting the buckle 8 and the ECU 100 can be reduced.

Further, according to the first embodiment, compatibility with a buckle in which the occupant sensor 12 is not mounted can be ensured. That is, without changing the connection interface with the buckle 8 on the ECU 100 side, the ECU 100 can acquire the detection state of the buckle switch 13 even if a buckle on which the occupant sensor 12 is not mounted is connected.

<Second Embodiment>
FIG. 18 is a block diagram illustrating an example of the configuration of the in-vehicle system 1B. The description of the same configuration as that of the first embodiment is omitted or simplified by using the above description.

In the example shown in FIG. 18, the main body 8 a of the buckle 8 has at least two terminals 15 and 16, and the ECU 100 has at least two terminals 102 and 103. The in-vehicle system 1B includes a wiring 18 that connects the terminal 15 and the terminal 102 to each other, and a wiring 19 that connects the terminal 16 and the terminal 103 to each other.

In the second embodiment, the buckle 8 includes terminals 15 and 16 as output terminals shared by the detection state of the buckle switch 13, presence / absence information, and physiological information. As a result, the number of wires connecting the buckle 8 and the ECU 100 can be further reduced. The buckle 8 outputs a signal obtained by superimposing the output information (presence / absence information or physiological information) of the occupant sensor 12 on the detection state of the buckle switch 13 from the terminals 15 and 16 by voltage modulation or current modulation.

FIG. 19 is a diagram showing an example of the configuration of the main body 8a of the buckle 8. As shown in FIG. FIG. 19 shows an embodiment in which two outputs of the buckle switch 13 and the occupant sensor 12 are integrated in accordance with the output specification of one buckle switch 13.

If the output of the buckle switch 13 and the output of the occupant sensor 12 are simply combined, the two output currents are summed. For example, when the sum of i-Sense and i-Out is the same as the output current i-Hole, the total current is doubled, which may exceed the current supply capability of the ECU 100.

In order to avoid this, the main body 8a of the buckle 8 includes a transistor 49 on the ground side of the transistor 41 and the Hall sensor 40. The MPU 30 can cut the output current i-Hole by turning off the transistor 49. In order to periodically detect the on state or the off state of the buckle switch 13, the MPU 30 turns on the transistor 49 to flow the output current i-Hole. The MPU 30 flows the output current i-Hole, and at the same time cuts the current I-Out by turning off the transistor 46. Thereby, the current supplied to the buckle 8 by the ECU 100 on the information receiving side is kept at one buckle switch 13.

FIG. 20 is a timing chart showing an example of the voltage output of the buckle switch 13 and the voltage output of the occupant sensor 12. FIG. 20 shows an example of operation waveforms of the configuration shown in FIG. In FIG. 20, the occupant sensor 12 detects a change from the absence of the occupant to the presence, and the buckle switch 13 detects the change from the buckle off to the buckle on. An example of switching to output of respiratory cycle information is shown.

FIG. 20 shows an embodiment in which the output of the occupant sensor 12 is superimposed on the output of the buckle switch 13.

When the tongue 7 and the buckle 8 are not connected, the transistor 41 is off (the buckle switch 13 is off). Since the transistor 41 is turned off, the output voltage at both ends of the buckle switch 13 (the voltage between the terminal 15 and the terminal 16) is higher than the threshold Th5. The buckle switch 13 outputs a voltage higher than the threshold Th5 from the terminals 15 and 16 as a signal indicating a non-connected state where the tongue 7 and the buckle 8 are not connected.

The MPU 30 executes the presence / absence determination of the occupant 11 when a voltage higher than the threshold Th5 is detected through the resistor 45.

When the presence of the occupant 11 is not detected, the MPU 30 always turns off the transistor 46, thereby increasing the output voltage (voltage between the terminal 15 and the terminal 16) at both ends of the occupant sensor 12 above the threshold Th5. . The occupant sensor 12 outputs a voltage higher than the threshold Th5 from the terminals 15 and 16 as the absence information of the occupant 11.

When the occupant gets into the vehicle when the buckle switch 13 is off and the presence of the occupant 11 is not detected, the MPU 30 detects the presence of the occupant 11. When the presence of the occupant 11 is detected, the MPU 30 turns on / off the transistor 46 to output a pulse voltage having a first cycle that repeatedly crosses the threshold Th5. The occupant sensor 12 outputs the pulse voltage of the first cycle from the terminals 15 and 16 as the presence information of the occupant 11.

When the tongue 7 and the buckle 8 are connected, the transistor 41 is turned on (the buckle switch 13 is turned on). When the transistor 41 is turned on, the output voltage across the buckle switch 13 is lower than the threshold value Th5. The buckle switch 13 outputs a voltage lower than the threshold value Th <b> 5 from the terminals 15 and 16 as a signal indicating a connection state in which the tongue 7 and the buckle 8 are connected.

The MPU 30 detects the physiological information of the occupant 11 when a voltage lower than the threshold Th5 is detected through the resistor 45.

When the voltage lower than the threshold value Th5 is detected via the resistor 45, the MPU 30 regards the occupant 11 as wearing the seat belt 4 and detects physiological information such as a respiratory cycle. When it is detected that the buckle switch 13 is turned on, the MPU 30 turns on / off the transistor 46 to output a pulse voltage having a second period that repeatedly crosses the threshold Th5. The occupant sensor 12 outputs the pulse voltage of the second period from the terminals 15 and 16 as physiological information of the occupant 11.

The second cycle is different from the first cycle. In the illustrated example, the second period is longer than the first period, but may be shorter than the first period.

For example, when the occupant 11 is seated but the buckle 8 and the tongue 7 are not connected, the buckle switch 13 outputs the voltage when it is off. However, since the occupant sensor 12 detects the occupant's seating, the occupant sensor 12 superimposes on the output voltage of the buckle switch 13 a belt remind signal (that is, an occupant 11 presence signal) that prompts the user to fasten the seat belt 4. The MPU 30 of the occupant sensor 12 outputs an on-pulse of 10 msec once per second, for example (see FIG. 20). The ECU 100 can receive the belt remind signal by detecting the 10 msec on-pulse.

When the buckle 8 and the tongue 7 are connected, the buckle switch 13 outputs the voltage when it is on. When the MPU 30 of the occupant sensor 12 detects respiration by the sensor 20, the MPU 30 outputs an off pulse of 10 msec in synchronization with the detected respiration cycle (see FIG. 20). For example, the MPU 30 outputs an off pulse of 10 msec once every 2 seconds. The ECU 100 can receive the respiratory cycle by detecting the 10 msec off-pulse.

When the ECU cannot receive presence / absence information and physiological information, the ECU cannot detect the extremely short 10 msec on-pulse and off-pulse output from the buckle 8 and can detect only the detection state of the buckle switch 13. Therefore, the buckle 8 can be shared regardless of whether the ECU has a configuration capable of receiving presence / absence information and physiological information. That is, it is possible to determine whether or not to equip the vehicle with a belt reminder system or a physiological information detection system simply by replacing the buckle.

FIG. 21 is a timing chart showing an example of the current output of the buckle switch 13 and the current output of the occupant sensor 12. FIG. 21 shows an example of the operation waveform of the configuration shown in FIG. 19 as in the case of FIG. In FIG. 21, as in the case of FIG. 20, the occupant sensor 12 detects the change from the absence of the occupant to the presence, and the buckle switch 13 detects the change from the buckle off to the buckle on. An example of switching from the output of presence information to the output of occupant respiratory cycle information will be shown.

When the current output of the buckle switch 13 and the current output of the occupant sensor 12 are collected, the output currents of both are added together. FIG. 21 shows an example in which the current value of i-Out is approximately halved with respect to i-Hole.

ECU100 determines that the buckle switch 13 is OFF when it is detected that a current lower than the current threshold Th12 is output from the terminal 15. On the other hand, when it is detected that a current higher than the current threshold Th12 is output from the terminal 15, the ECU 100 determines that the buckle switch 13 is on.

Further, when it is detected that a current lower than the current threshold Th12 is output from the terminal 15, the ECU 100 detects that a current lower than the current threshold Th13 is output from the terminal 15, Is determined not to exist. When it is detected that a current lower than the current threshold Th12 is output from the terminal 15, the ECU 100 detects a pulse straddling the current threshold Th13 as occupant presence information. When it is detected that a current higher than the current threshold Th12 is output from the terminal 15, the ECU 100 detects a pulse straddling the current threshold Th11 as physiological information.

FIG. 22 is a timing chart showing another example of the current output of the buckle switch 13 and the current output of the occupant sensor 12. FIG. 22 shows an example of the operation waveform of the configuration shown in FIG. 19 as in the case of FIG. In FIG. 22, as in the case of FIG. 20, the occupant sensor 12 detects a change from the absence of the occupant to the presence, and the buckle switch 13 detects the change from the buckle off to the buckle on. An example of switching from the output of presence information to the output of occupant respiratory cycle information will be shown.

ECU100 determines that the buckle switch 13 is ON when it is detected that the current within the first current value range R1 is output from the terminal 15. On the other hand, when it is detected that the current within the second current value range R2 is output from the terminal 15, the ECU 100 determines that the buckle switch 13 is off.

Further, when it is detected that a current lower than the current threshold Th6 within the second current value range R2 is output from the terminal 15, the ECU 100 determines that no occupant is present. When it is detected that a current within the second current value range R2 is output from the terminal 15, the ECU 100 detects a pulse straddling the current threshold Th6 as occupant presence information. The ECU 100 detects, as physiological information, a pulse that straddles the current threshold value Th7 in the first current value range R1 when it is detected that the current in the first current value range R1 is output from the terminal 15. To do.

As described above, the buckle and the in-vehicle system have been described in the embodiment, but the present invention is not limited to the above embodiment. Various modifications and improvements such as combinations and substitutions with some or all of the other embodiments are possible within the scope of the present invention.

For example, presence / absence information and physiological information generated by the occupant sensor 12 may be output from a communication terminal which is at least one of the terminals 14, 15, and 16 by a predetermined communication method. Specific examples of communication methods include LIN (Local Interconnect Network) and CAN (Controller Area Network). The occupant sensor 12 can encode presence / absence information and physiological information as communication data and transmit the encoded data as serial data. The serial data can include the detection state of the buckle switch. Therefore, the ECU on the receiving side can receive not only the presence / absence information and physiological information but also the detection state of the buckle switch 13 only with the serial communication data.

The occupant sensor 12 may once transmit the detection state of the buckle switch 13 to the ECU 100 and switch the detection function of the occupant 11 using the detection state of the buckle switch 13 transmitted from the ECU 100. Furthermore, the occupant sensor 12 may switch the detection function of the occupant 11 or the type of detection information to be output according to vehicle information transmitted from the ECU 100 (information that cannot be obtained only by the buckle).

Further, the occupant sensor 12 may be a means for detecting the movement of the occupant by electromagnetic waves such as infrared rays, or may be a means for detecting the movement of the occupant by temperature. The occupant sensor 12 may output the body temperature or blood pressure of the occupant 11 to the ECU 100 as vital sign information.

Further, the seat 2 may be a front seat of the vehicle or a rear seat.

This international application claims priority based on Japanese Patent Application No. 2016-101877 filed on May 20, 2016. The entire contents of Japanese Patent Application No. 2016-101877 are hereby incorporated by reference. Incorporated into.

DESCRIPTION OF SYMBOLS 1 Seatbelt system 1A, 1B In-vehicle system 8 Buckle 8a Body part 12 Passenger sensor 13 Buckle switch 20 Sensor 26 Presence / absence information detection part 27 Physiological information detection part 28 Ground 40 Hall sensor 44 Light emitting diode 100, 100A, 100B ECU

Claims (12)

1. A body portion connectable with a tongue attached to a vehicle seat belt;
   A buckle switch for detecting the presence or absence of connection between the tongue and the main body;
   An occupant sensor for detecting an occupant on a seat of the vehicle,
   The occupant sensor is a buckle that switches a detection function of the occupant using a detection state of the buckle switch.
2. The buckle according to claim 1, wherein the occupant sensor switches a detection function of the occupant according to the difference in the detection state.
3. The buckle according to claim 1, wherein the occupant sensor switches and outputs the occupant presence / absence information and the occupant physiological information according to the difference in the detection state.
4. The occupant sensor outputs the presence / absence information when the buckle switch does not detect the connection, and outputs the physiological information when the buckle switch detects the connection. The listed buckle.
5. The occupant sensor outputs the presence / absence information without outputting the physiological information when the buckle switch does not detect the connection, and the presence / absence information when the buckle switch detects the connection. The buckle according to claim 4, wherein the physiological information is output without outputting.
6. When the presence of the occupant is detected and the connection is not detected by the buckle switch, the occupant sensor outputs from the output of the occupant presence / absence information to the output of remind information for prompting wearing of the seat belt or the physiology of the occupant The buckle according to claim 1, wherein the buckle is switched to output of target information.
7. The buckle according to claim 1, further comprising an output terminal shared for outputting the presence / absence information of the occupant and physiological information of the occupant.
8. The buckle according to claim 1, further comprising an output terminal shared by the detection state of the buckle switch, the presence / absence information of the occupant, and the physiological information of the occupant.
9. The buckle according to claim 7, wherein the output terminal outputs a signal in which detection information by the occupant sensor is superimposed on a detection state of the buckle switch.
10. The buckle according to claim 7, wherein the output terminal is a communication terminal.
11. An in-vehicle system comprising: the buckle according to claim 1; and a receiving device that receives detection information from the occupant sensor.
12. A vehicle seat belt,
    A tongue attached to the seat belt;
    A buckle connectable with the tongue,
    The buckle is
    A buckle switch for detecting whether or not the tongue and the buckle are connected;
    An occupant sensor for detecting an occupant on a seat of the vehicle,
    The occupant sensor uses a detection state of the buckle switch to switch the occupant detection function.

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