JP2014084069A - Occupant detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely detect whether an occupant is seated or not with high durability.SOLUTION: An occupant detection device is arranged on a vehicular seat 1, and is structured by including a seating sensor 10 provided with a seating part 4 and an ECU 20 for detecting the seating status based on a signal from the seating sensor 10. The seating part 4 includes an embedded cushion pad 5 and a seat pan 7 arranged beneath the cushion pad 5 and supporting the cushion pad 5. The seating sensor 10 has a spring switch type structure, and is arranged in a recessed groove part 5b formed on a bottom surface part 5a of the cushion pad 5 between the bottom surface part 5a of the cushion pad 5 and an upper surface part 7a of the seat pan 7.

Description

  The present invention relates to an occupant detection device that detects an occupant seated in a seat.

  2. Description of the Related Art Conventionally, for example, a seating detection device (for example, see Patent Document 1 below) for detecting an occupant seated on a seating portion of a seat mounted on a vehicle is known. The seating detection device includes a pressure-sensitive switch including a pair of electrodes disposed at a predetermined interval on a pair of films disposed on a seating surface of a seating portion, and based on a detection signal from the pressure-sensitive switch. To determine if they are seated.

Japanese Patent Laid-Open No. 9-315199

  However, in the conventional seating detection device disclosed in Patent Document 1 described above, the pressure-sensitive switch is disposed between the pad and the skin of the seating surface of the seating portion, so that the seating comfort to the seating portion, etc. However, since it is made of a thin sheet-like film, the durability is inferior. In addition, when a film-like pressure sensitive switch is used, it is difficult to adjust the load. In particular, when the film-like pressure sensitive switch is disposed on the bottom surface of the seat pad, there is a problem that the seating of the occupant cannot be detected accurately. .

  SUMMARY OF THE INVENTION An object of the present invention is to provide an occupant detection device that solves the above-described problems caused by the prior art and is highly durable and can accurately detect the presence or absence of an occupant.

  An occupant detection device according to the present invention is an occupant detection device arranged in a seating portion in which a cushion pad is built, and is provided between a bottom surface portion of the cushion pad and a support member of the cushion pad. A seating sensor of the type is provided.

  According to the occupant detection device of the present invention, since it includes a spring switch type seating sensor provided between the bottom surface of the cushion pad and the support member of the cushion pad, it is more durable than conventional pressure sensitive switches. The structure can be high. In addition, since a spring switch type seating sensor is used as the seating sensor, it is possible to accurately adjust the sensitivity to the load, and whether or not the occupant is seated on the seating part even when it is placed on the bottom surface of the cushion pad Can be accurately detected based on the load on the cushion pad.

  In one embodiment of the present invention, the seating sensor is disposed in a groove provided in the bottom surface of the cushion pad. In addition, since sensitivity adjustment can be performed accurately as described above, in another embodiment, only one seating sensor needs to be provided in the seating portion. Moreover, in other embodiment, a seating sensor is arrange | positioned in the front side rather than the downward direction of the hip point of the human body seated on the said seating part, or this downward direction.

  According to the present invention, it is highly durable and can accurately detect the presence or absence of an occupant's seating.

It is a side view showing a seat provided with a crew member detection device concerning one embodiment of the present invention. It is a top view which shows a part of seat provided with the passenger detection device. It is a top view which shows the passenger detection apparatus. FIG. 4 is a cross-sectional view taken along the line A-A ′ of FIG. 3. It is a side view which shows the operation state of a seating sensor. It is a side view which shows a seat provided with the passenger | crew detection apparatus which concerns on other embodiment of this invention. It is a top view which shows a part of seat provided with the passenger detection device. It is a top view which shows the other structure of a seating sensor. It is B-B 'sectional drawing of FIG. It is sectional drawing which shows other structure of a seating sensor.

  Hereinafter, an occupant detection device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a side view showing a seat including an occupant detection device according to an embodiment of the present invention. FIG. 2 is a plan view showing a part of a seat including an occupant detection device. 3 is a plan view showing the occupant detection device, FIG. 4 is a cross-sectional view taken along the line A-A ′ of FIG. 3, and FIG. 5 is a side view showing the operating state of the seating sensor.

  As shown in FIGS. 1 and 2, the occupant detection device according to the present embodiment is disposed on a vehicle seat 1 including a headrest 2, a backrest portion 3, and a seating portion 4, and a seating provided on the seating portion 4. The sensor 10 includes an ECU 20 that detects the presence or absence of seating based on a signal from the seating sensor 10.

  The seat portion 4 of the seat 1 includes a cushion pad 5 made of a cushioning material such as urethane, and a seat pan 7 as a support member that is disposed below the cushion pad 5 and supports the cushion pad 5. ing. The seat pan 7 is made of a plate-like processed and molded member that contacts the entire bottom surface portion 5 a of the cushion pad 5 and supports the cushion pad 5.

  The seating sensor 10 has a so-called spring switch type structure. Specifically, the seating sensor 10 is disposed between the bottom surface portion 5a of the cushion pad 5 and the top surface portion 7a of the seat pan 7, and is, for example, in a concave groove portion 5b formed on the bottom surface portion 5a of the cushion pad 5. Has been placed.

  Further, at least one (one in this example) is disposed in the seating sensor 4 directly below (downward) or forward of the hip point P of the human body 9 on the seating surface 4a of the seating portion 4. According to the applicant's research, in the seating portion 4 of the seat 1 of the type including the backrest portion 3, the most load is applied to the lower side (directly below) of the hip point P or the front side thereof when the seating is present. This is because it was found to be a place. Since the seat 1 has the backrest part 3, the force acts also on the front side due to the force of the backrest part 3 pushing the back, so that the displacement amount due to the presence / absence of seating on the front side rather than the hip point P increases. And the seating sensor 10 is electrically connected with ECU20 mounted in the vehicle. The ECU 20 is a control circuit that controls the entire vehicle and controls the operation of various auxiliary devices such as airbag deployment control based on a signal from the seating sensor 10.

  As shown in FIGS. 3 and 4, the seating sensor 10 has, for example, a disc-like outer shape when viewed from the top and bottom, and an upper substrate 11 and a lower substrate 12 that face each other, and a plurality of circumferential positions therebetween. The arranged compression spring 19, the circuit electrode 17 provided via the insulator 15 at the central contact portion 13 of the upper substrate 11, and the insulator 16 provided at the central contact portion 14 of the lower substrate 12. The circuit electrode 18 is provided. The contact portions 13 and 14 are formed by, for example, pressing the upper substrate 11 and the lower substrate 12 made of a metal plate so as to approach each other by pressing. Further, when the upper substrate 11 and the lower substrate 12 are formed of an insulator such as a resin, the insulators 15 and 16 are unnecessary.

  The plurality of compression springs 19 that support the upper substrate 11 and the lower substrate 12 support, for example, the upper substrate 11 and the lower substrate 12 in a direction away from each other with a predetermined spring force. In a state where the elastic force is taken into account, for example, when a load of 40 kg or more is applied, it has a spring characteristic that contracts in the direction in which the circuit electrodes 17 and 18 come into contact with each other.

  The surface of the upper substrate 11 opposite to the circuit electrode 17 forming side is fixed to the groove bottom surface portion 5c of the groove portion 5b of the cushion pad 5, and the surface of the lower substrate 12 opposite to the circuit electrode 18 forming side is fixed to the seat pan 7 Is fixed to the upper surface portion 7a. The circuit electrodes 17 and 18 are connected to the ECU 20 via unillustrated wiring patterns and cables formed on the substrates 11 and 12, and are electrically connected to each other by contact.

  As shown in FIG. 5A, the seating sensor 10 is supported in the direction in which the substrates 11 and 12 are separated by the spring force of the compression spring 19 when no load is applied to the seating surface 4 a of the seating portion 4. As shown in FIG. 5B, when a load as indicated by an open arrow is applied to the seating surface 4a, each substrate is resisted against the spring force of the compression spring 19. 11 and 12 approach and circuit electrodes 17 and 18 operate.

  In the occupant detection device 1 configured in this manner, the seating sensor 10 has a spring switch type structure provided between the groove portion 5b of the bottom surface portion 5a of the cushion pad 5 and the upper surface portion 7a of the seat pan 7. Compared with a conventional pressure-sensitive switch, it can have high durability, and a sensor structure with a large displacement can be obtained.

  When a predetermined load about the weight of the human body 9 is applied to the seating surface 4a of the seating portion 4, the upper substrate 11 and the lower substrate 12 move in a direction approaching against the spring force of the compression spring 19, and contact points Since the circuit electrodes 17 and 18 come into contact with each other at the portions 13 and 14 and the conduction is achieved, and the spring constant of the compression spring 19 can be accurately adjusted, it is possible to accurately detect the presence or absence of human seating. it can. In addition, since the spring switch type seating sensor 10 can accurately detect an occupant, the spring switch type seating sensor 10 is arranged in front of the hip point of the human body to which the most load is applied. Occupant detection is possible. For this reason, cost reduction can be aimed at.

  FIG. 6 is a side view showing a seat provided with an occupant detection device according to another embodiment of the present invention. FIG. 7 is a plan view showing a part of a seat provided with an occupant detection device. As shown in FIGS. 6 and 7, the occupant detection device according to the present embodiment uses an S spring frame as a spring frame instead of the seat pan 7 as a support member that supports the cushion pad 5 of the seating portion 4 of the seat 1. 6 is different from the occupant detection device according to the previous embodiment.

  The S spring frame 6 is formed by forming a round bar-shaped metal member such as iron into an S shape, and is in contact with the bottom surface portion 5 a of the cushion pad 5. The seating sensor 10 has, for example, a surface opposite to the circuit electrode 18 formation side of the lower substrate 12 attached and fixed to the bent portion 6a of the S spring frame 6 or a clip-like holder 18 provided in the vicinity thereof. The cushion pad 5 is disposed in the groove portion 5 b of the bottom surface portion 5 a. The bent portion 6a is suitable for the placement of the seating sensor 10 because the S spring frame 6 is difficult to be displaced in the horizontal direction. Even if comprised in this way, there can exist an effect similar to the above, and the amount of set displacement of the compression spring 19 of the seating sensor 10 can be reduced by the amount of deflection of the S spring frame 6 as compared with the previous embodiment. Can do.

  In the above-described embodiment, for example, when a plurality of seating sensors 10 are provided in the seating portion 4, the seating sensors 10 are arranged in series with respect to the ECU 20 after being arranged at a location where the load of the human body 9 can be detected. May be connected. In this way, since the circuit is connected only according to the load when the human body 9 is seated on the seating portion 4, for example, erroneous detection when an object such as a heavy load is placed on the seat surface 4a. Can be avoided.

  Further, when a plurality of seating sensors 10 are provided in parallel connection, if the load distribution on the seat surface 4a can be detected by the ECU 20 or the like based on the detected current value or the like, the seating of the human body 9 on the seating portion 4 is possible. And the placement of an object can be detected more finely, so that the discrimination accuracy can be improved.

  FIG. 8 is a plan view showing another structure of the seating sensor. FIG. 9 is a cross-sectional view taken along the line B-B ′ of FIG. 8. As shown in FIGS. 8 and 9, the seating sensor 10 </ b> A having another structure is formed at three or more locations in the circumferential direction of the upper substrate 11 made of, for example, a circular metal plate, instead of the compression spring 19 of the previous seating sensor 10. The point which is provided with the elastic piece 19a which comprises the made leaf | plate spring is different. The elastic piece 19a supports the upper substrate 11 and the lower substrate 12 in a direction in which they are separated from each other with a predetermined elastic force, for example. Similarly to the compression spring 19, the elastic piece 19a also bends in the direction in which the circuit electrodes 17 and 18 come into contact with each other when a load of 40 kg or more is applied in a state where the elastic force of the cushion pad 5 is taken into account. It has.

  FIG. 10 is a sectional view showing still another structure of the seating sensor. As shown in FIG. 10, a seating sensor 10B having still another structure has a dome-shaped metal provided on the lower substrate 12, for example, instead of the compression spring 19 of the previous seating sensor 10 and the elastic piece 19a of the seating sensor 10A. The circuit electrode 17 is constituted by the reversal spring of the member, the circuit electrode 18 is formed at a position facing the circuit electrode 17 through the insulator 16, and the plunger 17a for deforming the dome shape of the circuit electrode 17 is opposed to the upper substrate 11. The arrangement is different. Even if it is such a structure, there can exist an effect similar to the above.

DESCRIPTION OF SYMBOLS 1 Seat 2 Headrest 3 Backrest part 4 Seating part 4a Seat surface 5 Cushion pad 6 S Spring frame 7 Seat pan 9 Human body 10 Seating sensor 11 Upper board 12 Lower board 13, 14 Contact part 15, 16 Insulator 17, 18 Circuit electrode 19 Compression spring 20 ECU

Claims (4)

An occupant detection device arranged in a seating part with a built-in cushion pad,
An occupant detection device comprising a spring switch type seating sensor provided between a bottom surface portion of the cushion pad and a support member of the cushion pad.   The occupant detection device according to claim 1, wherein the seating sensor is disposed in a groove provided in a bottom surface of the cushion pad.   The occupant detection device according to claim 1, wherein one seating sensor is provided in the seating portion.   The occupant detection device according to any one of claims 1 to 3, wherein the seating sensor is disposed below a hip point of a human body seated on the seating portion or on a front side of the lower side.

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