JP5903923B2 - Seating load detector - Google Patents

Description

  The present invention relates to an apparatus for detecting a seating load of an occupant installed on a vehicle seat.

  Conventionally, in order to improve the performance of various safety devices such as seat belts and airbags installed in automobiles, there are cases where these safety devices are controlled by detecting the state in which an occupant is seated on the seat. However, in addition to a person sitting on the seat, a luggage may be placed, and it is extremely important to correctly distinguish the person from the luggage to correctly operate the safety device.

  A thin and flexible membrane switch is conceivable as suitable for detecting the seating state of such an occupant, and a seating sensor using such a membrane switch is disclosed in Patent Document 1. The seating sensor includes a first film formed in a straight line, a second film formed in the same shape as the first film, and disposed opposite to the first film, and the first film and the second film. Sensor electrodes (contact / separation part and contact / separation part) of two sensor cells (pressure-sensitive switch) that are arranged oppositely and spaced apart and are brought into contact with each other when receiving a load, and a first film, The conductive electrode (switch wiring) in the conductive part that is arranged between the second film and conductive to the sensor electrode is coupled to the ends of the first film and the second film, and is connected to the sensor electrode through the conductive electrode. The connector part is described. And this seating sensor is placed on the seat surface so that it is oriented obliquely with respect to the vehicle longitudinal direction and the vehicle left-right direction, and when the occupant is seated in the correct posture, two sensor cells are placed in the part that hits the occupant's buttocks It is described that it is done.

JP 2008-157914 A

  However, as shown in FIGS. 16 and 17, for the linear seating sensor, the seat cushion 102 is provided with a through hole (insertion hole) 104, and the sensor cell 116 is disposed on the seat surface on the front side of the seat cushion 102, and the through hole is formed. In many cases, the base portion 108 of the membrane switch 106 and the connector portion 110 are passed through the portion 104, and the connector portion 110 is disposed on the back side of the seat cushion 102. In this case, the main body portion of the membrane switch 106 is arranged in a bent state, and the bent outer film (first film) 112 and the inner film (the first film) 112 of the membrane switch 106 formed by overlapping a plurality of films are formed. A peripheral length difference occurs with respect to the second film) 114. For this reason, the strain of stress due to bending spreads to the sensor cell (pressure-sensitive switch) 116, for example, the second film 114 side of the sensor cell 116 swells, and the distance and the shape between the films that conduct oppositely change. For this reason, there has been a problem that the sensor cannot be turned on or turned on with a load larger than the intended load, so that an appropriate load of the occupant cannot be detected.

  The present invention has been made in view of the conventional problems, and provides a seating load detection device that correctly detects the seating state of an occupant even when the seating load detection device is bent and disposed on a vehicle seat cushion. To do.

In order to solve the above-described problem, the structural feature of the invention according to claim 1 is that, in the seating load detection device, a plurality of contact / separation parts constituting a pressure-sensitive switch for detecting the seating of an occupant have a predetermined interval. A band-shaped first film formed with a gap and formed with a switch wiring that connects between the contact and separation portions, and disposed opposite to the first film, constitutes the pressure sensitive switch, and is disposed on the contact and separation portions. A band-shaped second film formed with a plurality of contacting / separating portions, and a through hole formed between the first film and the second film and facing the plurality of pressure sensitive switches. And a separation member formed with an air passage that communicates with each through hole and communicates with the atmosphere, and is provided at a base end portion of the first film and the separation member, and the pressure sensitive switch Detected by A seating load detection device comprising: an external output unit that outputs a heavy signal; and a conduction unit that conducts between the pressure-sensitive switch and the external output unit, wherein the conduction unit includes the pressure-sensitive switch. It includes a curved portion mounted curved when attached to the seating surface of the vehicle seat, wherein the curved portion is constituted by said first film and said separation member except the second film, said separation member The air passage opens at the end of the bending portion on the pressure-sensitive switch side, and the separation member between the end of the bending portion on the pressure-sensitive switch side and the external output portion is the air passage is solid member der Rukoto is not formed.

  According to the first aspect of the invention, the seating load detection device mainly formed from the first film, the second film, and the separation member disposed between the two films is curvedly attached to the vehicle seat. And a circumference difference arises between the 2nd film which becomes inner when it curves, and the 1st film which becomes the outside. Therefore, in the related art, the first film and the second film are in the contact / separation part and the contact / separation part corresponding to the through hole that is not bonded to the separation member, either or both of the first film and the second film are Distortions such as swelling in directions away from each other or shrinking in directions closer to each other occur.

However, in the present invention, when the pressure-sensitive switch is attached to the seating surface of the vehicle seat, the bending portion that is bent and attached is constituted by the first film and the separation member excluding the second film, and the second film. Since the thickness is reduced by the amount excluding, the circumferential length difference generated in the curved portion is reduced. Furthermore, since there is no second film in the bending portion, the distortion due to the bending portion is not propagated to the second film constituting the pressure sensitive switch. Therefore, in the pressure-sensitive switch, distortion based on the difference in circumference between the first film and the second film is reduced, and the separation distance between the contacted / separated portion and the contact / separation portion of the pressure-sensitive switch changes due to the strain. Can be prevented. Thereby, even when the seating load detection device is curved and arranged, the seating load of the occupant can be detected with high accuracy.
Further, since the separation member is a solid member in which no air passage is formed in the curved portion, it is possible to prevent moisture from entering from the air passage in the conduction portion.

The figure which shows the state which has arrange | positioned the seat cushion for vehicles to the seating load detection apparatus which concerns on this invention. The top view of a seating load detection apparatus. III-III sectional drawing of a seating load detection apparatus. The bottom view which expands and shows a part of 1st film. The top view which expands and shows a part of separation member. The top view which expands and shows a part of 2nd film. The conceptual diagram which shows the side cross section of a seating load detection apparatus. The circuit diagram of a seating load detection apparatus. The circuit diagram of the seating load detection apparatus of another example. The figure which shows the state by which the seating load detection apparatus was curved and was arrange | positioned at the vehicle seat. The figure which expands and shows a part of FIG. The figure which shows the 1st film of the seating detection apparatus of another example. The figure which shows the insulation spacer of the seating detection apparatus of another example. The figure which shows the 2nd film of the seating detection apparatus of another example. Sectional drawing of the pressure-sensitive switch part of the seating detection apparatus of another example. The conceptual diagram which shows the side cross section of the conventional seating load detection apparatus. The figure which shows the state by which the conventional seating load detection apparatus was curved and arrange | positioned at the vehicle seat.

  Hereinafter, an embodiment in which a seating load detection device according to the present invention is applied to a vehicle seat will be described with reference to the drawings. FIG. 1 is a perspective view showing a seating surface of a seat cushion 2 of a vehicle seat for a single seat.

  As shown in FIG. 1, the seat cushion 2 includes a pad member 4 made of urethane or the like, and a cloth (or leather, etc.) skin member 6 that is mounted so as to cover the seating side surface of the pad member 4. ing. On the upper surface of the pad member 4 of the seat cushion 2, a concave groove 8 extending in the left-right direction is recessed. An insertion hole 12 into which the base end portion of the seating load detection device 10 penetrating from the upper surface to the lower surface of the pad member 4 is inserted in the rear center portion of the seat surface of the pad member 4.

  The seating load detection device 10 mainly includes a membrane switch 19 formed by superposing the paired first film 14 and second film 16 via an insulating spacer 18 as a separation member. The membrane switch 19 is formed in an elongated strip shape as shown in FIGS. The membrane switch 19 includes four pressure-sensitive switches A, B, C, and D, and pressure-sensitive switch switch wiring (switch wiring) 20 that connects the pressure-sensitive switches A, B, C, and D on the first film 14. And a conduction portion 26 provided with a pressure sensitive switch / connector portion switch wiring (switch wiring) 22 between the pressure sensing switch D on the most proximal side and the connector portion 24 provided at the proximal end portion. And have.

  The first film 14 is made of, for example, PEN (polyethylene naphthalate) with a thickness of 0.1 mm, and as shown in a bottom view in FIG. 4, is a pressure-sensitive switch connector that conducts to the positive and negative electrodes of the connector portion 24, respectively. The inter-unit switch wiring 22 is formed substantially in parallel by printing or the like. The portions of the first film 14 corresponding to the pressure sensitive switches A, B, C, and D are formed in a substantially circular shape and wide, and the wide portions are connected to switch wires 20 and 22 that are respectively connected to one electrode. A circular contact / separation portion 28 is formed by printing or the like.

The insulating spacer 18 is made of, for example, 0.15 mm PET (polyethylene terephthalate), and has a circular shape penetrating in the thickness direction at portions corresponding to the pressure sensitive switches A, B, C, and D as shown in a plan view in FIG. Each through hole 30 is provided. An air passage 32 that penetrates in the thickness direction and has a width-direction dimension of 0.15 mm opens in the side wall of each through-hole 30, and the air passage 32 is the second in the vicinity of the pressure-sensitive switch D on the most proximal side. It connects with the air vent 33 (refer FIG. 7) provided in the edge part of the film 16, and communicates with air | atmosphere. The insulating spacer 18 on the base end side with respect to the vent 33 is formed in a solid shape with a rectangular cross section in which the air passage 32 is not provided (solid member). The remaining portion 34 is constituted by the solid portion.
In addition, each numerical value described here shows an example of implementation and can be appropriately changed.

  As shown in a plan view in FIG. 6, the second film 16 is formed in the same shape as the first film 14 with respect to the portion excluding the conductive portion 26, and the portions corresponding to the pressure sensitive switches A, B, C, and D are formed. A circular contact / separation portion 36 made of a conductive material is formed by printing or the like. The contact / separation part 36 corresponding to the pressure sensitive switch A and the pressure sensitive switch C is electrically connected by the switch wiring 20 between the pressure sensitive switches, and the contact / separation part 36 corresponding to the pressure sensitive switch B and the pressure sensitive switch D is pressure sensitive. They are electrically connected by an inter-switch switch wiring 20. Further, the pressure-sensitive switch switch wiring 20 that connects the pressure-sensitive switches AC and the pressure-sensitive switch-switch wiring 20 that connects the pressure-sensitive switches BD are electrically connected by a connection line 35. Further, as shown in FIG. 7, the second film 16 ends when it is slightly closer to the connector part 24 side than the most proximal pressure-sensitive switch D, and the first film 14 extends from the end position to the connector part 24. And the insulating spacer 18 are bonded to each other with an adhesive layer 25 to which an adhesive is applied. An adhesive material 27 is provided on the back surface of the second film 16, and the pressure sensitive switches A to D are fixed to the seating surface of the pad member 4 of the seat cushion 2.

  In addition, the second film 16 and the insulating spacer 18 are also overlapped and bonded by the above-described adhesive (adhesive layer 25), and the first film, the insulating spacer, and the second film are overlapped and bonded, Moisture does not enter from the outside. In this way, by overlapping and adhering films or the like, each through hole 30 forms a space for contacting / separating the contact / separation part 28 of the first film 14 and the contact / separation part 36 of the second film 16. To do. A circular contact / separation portion (upper electrode) 28 disposed on the first film 14 and a circular contact / separation portion (lower electrode) 36 disposed on the second film 16 sandwich the through hole 30. When the load in the thickness direction is applied to the pressure sensitive switches A, B, C, and D, the contact / separation part 36 and the contact / separation part 28 are brought into contact with each other and turned on. The flowing current is detected. As shown in FIG. 8, the pressure sensitive switches A, B, C, and D include two pressure sensitive switches A and pressure sensitive switches C that are in series with the proximal end side and the distal end side, and the contact / separation portions 36 and the contact / separation portions. Is turned on when a contact is made at the same time, or when the contact / separation part 36 and the contact / separation part 28 in the pressure sensitive switch B and the pressure sensitive switch D are contacted at the same time, the current is detected. ing. The contact / separation portion 36 and the contact / separation portion of the pressure-sensitive switch A and the pressure-sensitive switch D are connected by a connection line 35 that connects the switch wiring between the pressure-sensitive switches A and C and the switch wiring between the pressure-sensitive switches B and D. 28, when the contact / separation part 36 and the contact / separation part 28 of the pressure sensitive switch B and the pressure sensitive switch C are simultaneously contacted, the current is detected. ing.

  An external output unit 38 is provided at the proximal end of the membrane switch 19. The external output unit 38 outputs a load detected by the pressure sensitive switch 20, and an output electrode is formed. A connector is connected to the external output unit 38 to constitute the connector unit 24. The connector portion 24 is connected to an unillustrated ECU (Electronic Control Unit) that determines the seating state of the occupant.

  When the base end of the membrane switch 19 is inserted into the insertion hole 12 of the pad member 4 as shown in FIGS. 10 and 11, and the base end is fixed to a frame (not shown) on the back surface of the seat cushion 2. The conductive portion 26 at a position slightly moved from the pressure-sensitive switch D on the most proximal side to the connector portion 24 side is bent downward to form a curved portion 40.

  In the curved portion 40, the first film 14 is extended outside the arc, and the insulating spacer 18 is compressed inside the arc. However, as shown in FIG. 11, since the second film 16 is not provided on the bending portion 40, the compressive force received by the insulating spacer 18 compressed by the second film 16 is small, and the first film 14 and the second film Deviation in the longitudinal direction due to the difference in peripheral length between the film 16 and the film 16 is extremely small. Therefore, the distance between the contact / separation part 36 and the contact / separation part 28 in the pressure sensitive switches A, B, C, and D is less likely to vary, and accurate load detection can be performed.

  In operation, as shown in the circuit diagram of FIG. 8, a set of pressure-sensitive switch A and pressure-sensitive switch C, a set of pressure-sensitive switch B and pressure-sensitive switch D, a pressure-sensitive switch A and a pressure-sensitive switch D In at least one of the group, the pressure-sensitive switch B and the pressure-sensitive switch C, when the pressure-sensitive switch constituting the same group is turned on at the same time, a current flows in the switch wiring 22 between the pressure-sensitive switch and the connector. A seating detection signal is output. For this reason, it is possible to prevent an occupant load from being detected by a load having a small area in contact with the load, and when the ECU determines that the person sitting on the seat cushion 2 is based on the seating detection signal based on the current. For example, the airbag device can be operated, or a warning that the seat belt is not worn is issued.

  According to the seating load detection device 10 configured as described above, the seating load detection mainly formed from the first film 14 and the second film 16 and the insulating spacer 18 disposed between the two films 14 and 16 is performed. When the device 10 is attached to the seat cushion 2 in a curved manner, a circumferential length difference is generated between the second film that becomes the inner side and the first film that becomes the outer side when the device 10 is bent. Therefore, conventionally, in the contact / separation part and the contact / separation part corresponding to the through hole in which the first film and the second film are not bonded to the separation member, either or both of the first film and the second film are mutually connected. Distortions such as swelling in the direction of separating or contracting in the direction of approaching each other occur.

  However, in the present invention, the bending portion 40 that is bent and attached when the pressure sensitive switches A, B, C, and D are attached to the seating surface of the seat cushion 2 is the first film 14 excluding the second film 16. In addition, since the thickness is reduced by the amount excluding the second film 16, the difference in circumferential length generated in the curved portion 40 is reduced. Furthermore, since the second film 16 does not exist in the bending portion 40, the distortion due to the bending portion 40 is not easily propagated to the second film 16 constituting the pressure sensitive switches A, B, C, and D. Therefore, in the pressure sensitive switches A, B, C, and D, distortion based on the circumference difference between the first film 14 and the second film 16 is prevented, and the pressure sensitive switches A, B, C, and D are prevented. It is possible to prevent the distance between the contact / separation portion 28 and the contact / separation portion 36 from changing due to the strain. Thereby, even when the conduction portion 26 of the seating load detection device 10 is curved and arranged, the seating load of the occupant can be detected with high accuracy.

  Further, since the insulating spacer 18 is a solid member in which the air passage 32 is not formed in the curved portion 40, it is possible to prevent moisture from entering from the air passage in the conduction portion 26. Although the air passage 32 penetrates from the thickness direction, the air passage 32 is not limited to this, and may be, for example, a through hole provided continuously in the longitudinal direction of the separation member.

  In the above embodiment, the pressure-sensitive switch A and the pressure-sensitive switch C, the pressure-sensitive switch B and the pressure-sensitive switch D, the pressure-sensitive switch A and the pressure-sensitive switch D, the pressure-sensitive switch B and the pressure-sensitive switch. In at least one of the pairs of pressure switches C, when the pressure sensitive switches constituting the same group are simultaneously turned on, a current flows through the pressure sensitive switch / connector switch wiring 22 and a seating detection signal is output. However, the present invention is not limited to this. For example, as shown in the circuit diagram of FIG. 9, a set of pressure-sensitive switch A and pressure-sensitive switch B, a set of pressure-sensitive switch C and pressure-sensitive switch D, and pressure-sensitive When at least one of the pair of the switch A and the pressure sensitive switch D and the group of the pressure sensitive switch B and the pressure sensitive switch C is simultaneously turned on, the pressure sensitive switch May be seated detection signal is outputted a current flows through the connector section between the switch wiring 22. As a result, a seating detection signal is output when at least adjacent pressure-sensitive switches are simultaneously turned on, so that the detection range can be easily adjusted, and a person who is scheduled to detect (for example, a woman or a child) It is possible to detect an accurate seating state in accordance with the size and shape of the object (for example, luggage or child seat).

  Further, as in the above-described embodiment and other examples thereof, in any one of the sets of pressure-sensitive switches A, B, C, and D (for example, a set of A and C), the pressure-sensitive switches in the same group are simultaneously turned ON. However, the present invention is not limited to this. For example, as shown in FIGS. 12 to 15, a membrane switch is used. The first film 54 in 52 is provided in a half-moon shape at positions corresponding to the switch wires 60 that are electrically connected in parallel to the respective electrodes and the pressure sensitive switches K, L, M, and N of the switch wires 60. A pair of contact / separation parts 64 is provided, and the second film 56 is provided with a contact / separation part 66 at a position facing the contact / separation part 64, and the contact / separation part 66 contacts the contact / separation part 64. Then, the contacted / separated portions 6 adjacent to each other in pairs To each other or it may be the ones to Dentsu. Also in this configuration, the insulating spacer 68 is provided with through holes 70 at positions corresponding to the pressure sensitive switches K, L, M, and N. When the base end portion of the membrane switch 52 is inserted into the insertion hole 12 of the pad member 4 and the base end portion is fixed to a frame (not shown) on the back surface of the seat cushion 2, the base end portion is the same as described above. The conductive portion at a position slightly moved from the pressure-sensitive switch N on the side to the connector portion side (not shown) is bent downward (not shown) to form a curved portion. The curved portion is configured by polymerizing the first film excluding the second film and the insulating spacer with an adhesive or the like as in the above-described embodiment.

  In this embodiment, if any one of the pressure sensitive switches K, L, M, and N is turned on, a seating detection signal is output. Other configurations and operational effects are the same as those of the above-described embodiment.

  Further, the membrane switch is not limited to a single band-like one, and for example, the detection unit in which the pressure sensitive switch is arranged may be divided into two forks or three forks.

  Moreover, although the conduction | electrical_connection part 16 shall be comprised by the 1st film 14 except the 2nd film 16 and the insulating spacer 18 over the whole, it is not limited to this, For example, it attaches among conduction | electrical_connection parts. Only the portion (curved portion) that is bent at that time may be constituted by the first film 14 excluding the second film 16 and the insulating spacer 18.

  Moreover, although the conduction | electrical_connection part 26 was made into the solid member without the air passage 32 in the remaining part 34, it is not limited to this, For example, the air passage may be provided in the remaining part.

  Thus, the specific configuration described in the above-described embodiment is merely an example of the present invention, and the present invention is not limited to such a specific configuration. Various embodiments can be adopted without departing from the scope.

  DESCRIPTION OF SYMBOLS 2 ... Seat cushion, 10 ... Seating load detection apparatus, 14 ... 1st film, 16 ... 2nd film, 18 ... Separation member (insulation spacer), 19 ... Seating load detection apparatus (membrane switch), 20 ... Switch wiring (sensation) Switch wiring between pressure switches), 22 ... switch wiring (switch wiring between pressure sensitive switch and connector part), 26 ... conducting part, 28 ... contact / separation part, 30 ... through hole, 32 ... air passage, 34 ... remaining part, 36 ... contact / separation part, 40 ... bending part, 52 ... seating load detection device (membrane switch), 54 ... first film, 56 ... second film, 60 ... switch wiring, 64 ... contact / separation part, 66 ... contact / separation part 68 ... Separation member (insulating spacer), 70 ... Through hole, A, B, C, D ... Pressure sensitive switch, K, L, M, N ... Pressure sensitive switch.

Claims (1)

A plurality of contact / separation portions constituting a pressure-sensitive switch for detecting the seating of an occupant are formed at a predetermined interval and a band-shaped first film on which switch wiring for connecting the contact / separation portions is formed; A strip-shaped second film that is disposed opposite to the first film and that forms the pressure-sensitive switch and has a plurality of contact / separation portions that are respectively contacted / separated with the contact / separation portions, and the first film and the second film And a separation member formed with through holes formed at positions facing the plurality of pressure sensitive switches and having air passages communicating with the through holes and communicating with the atmosphere. And
An external output unit that is provided at a base end portion of the first film and the separating member and outputs a load signal detected by the pressure-sensitive switch;
A seating load detection device comprising a conduction portion that conducts between the pressure-sensitive switch and the external output unit,
The conduction portion includes a bending portion that is bent and attached when the pressure-sensitive switch is attached to a seating surface of a vehicle seat,
The curved portion is composed of the first film excluding the second film and the separation member,
In the separation member, the air passage opens at an end of the curved portion on the pressure sensitive switch side,
The seating load detection device, wherein the separation member between the pressure-sensitive switch side end of the bending portion and the external output portion is a solid member in which the air passage is not formed.

Images