JP2007045237A - Air bag device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a switch with excellent operability capable of certainly recognizing stroke feeling of a switch provided on a steering wheel such as a horn switch by an occupant. <P>SOLUTION: The air bag device is constituted such that a decoration body attachment part 3b is formed on a cover body 3 for storing an air bag 2c and an ornament 4 is advanceably/retreatably attached to the decoration body attachment part 3b. The switch is arranged between a back surface of the decoration body 4 and the decoration body attachment part 3b and is constituted by a membrane switch panel 5 having an electrode 7 comprising an electrode part 7a at a positive electrode side and an electrode 7b at a negative electrode side; a conductor 10 for closing the electrode 7; and an elastic spacer 9 positioned between the electrode 7 and the conductor 10 and always relatively urging the electrode 7 and the conductor 10 in an opening direction. The electrode 7a at the positive electrode side and the electrode 7b at the negative electrode side are closed by the conductor 10 by pressing/acting the ornament 4 to a cover body 3 side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an airbag device that is preferably mounted on a center portion of a steering wheel in which a switch such as a horn operation switch is installed.

  When this type of airbag device is mounted on the center portion of a steering wheel, a structure with good operability of a switch such as a horn operation switch is required while ensuring the passenger protection performance of the airbag itself. Various developments have been made accordingly.

As such an airbag device, for example, the steering wheel is mounted on a steering wheel by supporting the airbag module on a spring, and the operation force is applied to the switch by operating the entire airbag module against the spring. In other words, a switch configured to open and close the switch, and a switch configured to open and close a membrane switch that is a switch by operating a decorative body provided on a cover body containing an airbag module are known. It has been. (See Patent Document 1 and Patent Document 2).
Japanese Patent Laid-Open No. 10-100907 JP-A-9-272391.

  The former airbag device usually has a structure part for supporting an airbag to be deployed and securely deploying and inflating an inflator in which a drug or high-pressure gas is sealed in a sturdy and heavy housing. Therefore, the so-called sprung load on the spring that supports this is increased, and the spring that supports the airbag has a strong spring force in order to prevent malfunction of the airbag due to various vibrations during traveling. As a reaction, it has been unavoidable that a certain limit appears in order to operate a switch such as a horn operation switch with a light operational feeling.

  Therefore, the latter is greatly limited by the load on the panel of the airbag device, as it was devised to open and close the switch such as the horn operation switch, regardless of the spring load of the airbag device. The switch with the horn operation switch can be opened and closed.

  That is, in the latter airbag device, a thin horn switch (membrane switch) is in close contact between the airbag module and a mark portion (decorative body) formed of a soft material provided on the airbag cover. It is configured to be sandwiched so that a hard pad for actuating the switch is not necessary, and the storage space of the airbag in the steering wheel is not eroded, without operating the airbag module itself. The switch is opened and closed by operating only the thin horn switch.

  However, since the thin horn switch is configured to open and close by pressing the soft mark part, it does not give a sense of switch stroke. The horn may sound loudly, and when the driver is concerned about this and operates with a small pressing force, it is difficult to understand the force. Since it doesn't sound at the timing that it wants to sound, the driver who is somewhat overwhelmed tries to apply a strong pressing force, but this time it pushes too hard, eventually resulting in a loud horn. That is, there has been a problem that it is not easy to operate a so-called greeting horn or the like for expressing gratitude. Therefore, if the spring strength is set so that it can be closed with a delicate operating force, the risk of causing an operation increases. For example, as a result of lowering the operation load, the trouble that the horn is ringing in an unattended parking lot at night must be avoided. Therefore, there is a limit to reducing the operation load naturally.

  Therefore, the present invention has been made to solve such a conventional problem, and enables the occupant to surely know the stroke feeling of a switch provided on a steering wheel such as a horn switch, and has excellent operability. It is an object of the present invention to provide an airbag device provided with a switch.

  The airbag device according to the present invention as set forth in claim 1 is configured such that a decorative body mounting portion is formed on a cover main body for storing an airbag, and the decorative body is mounted on the decorative body mounting portion so as to be able to advance and retreat. In the apparatus, a switch is disposed between the back surface of the decorative body and the decorative body mounting portion, and the switch includes a membrane switch panel having electrodes, a conductor for closing the electrodes, and the electrodes. The switch is closed by pressing the decorative body toward the cover main body, which is composed of an elastic spacer that is between the conductor and urges the electrode and the conductor relatively constantly in the opening direction. It is characterized by comprising.

  With this configuration, the switch can be closed by pressing the decorative body against the urging force of the elastic spacer toward the cover body, so that the operator can reliably sense the operation stroke feeling of the decorative body. When the switch is used as a horn switch, it is possible to always obtain a loud sound level suitable for the situation, and the decorative body is made of a hard material, so that the elastic spacer can be Therefore, the spring force of the elastic spacer can be reduced, and the opening / closing operation of the membrane switch panel can be performed with a light operation feeling.

  Further, in the airbag device according to the second aspect of the present invention, the decorative body is attached to the decorative body mounting portion via a central attachment leg, and the switch is located at a position surrounding the leg portion. A plurality of them are provided.

  With such a configuration, by providing a plurality of switches so as to surround the mounting leg, even if an arbitrary position of the decorative body is pressed, the electrode strokes due to the pressing operation of the decorative body toward the cover body. A conductor can close the electrode.

  According to a third aspect of the present invention, in the airbag device according to the present invention, the elastic spacer is provided with a bottomed cylindrical projection, and the conductor is disposed on the inner bottom wall of the projection. .

  With this configuration, the elastic spacer can stably bias and support the decorative body and the switch, and the conductor provided in the bottomed cylindrical projection is securely in contact with the electrode when not operated. The state can be maintained, and the operability can be improved without malfunction.

  According to a fourth aspect of the present invention, in the airbag apparatus according to the present invention, the conductor is integrally formed on the back side of the decorative body.

  With this configuration, the operation of the decorative body itself can be directly applied to the conductor, and intuitive operability can be obtained.

  According to the present invention, the switch can be closed by pressing the decorative body against the urging force of the elastic spacer toward the cover body, so that the operator can reliably feel the operation stroke of the decorative body. When the switch is used as a horn switch, it is possible to always obtain a loud sound level suitable for the situation, and to form the decorative body from a hard material, thereby forming an elastic spacer. Thus, the spring force of the elastic spacer can be reduced, and the opening / closing operation of the membrane switch panel can be performed with a light operation feeling.

  Embodiments of the present invention will be described in detail with reference to the drawings.

  1 is a plan view of a steering wheel according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1, FIG. 3 is an enlarged view within a dashed-dotted line in FIG. FIG. 5 is an exploded perspective view of the membrane switch panel, FIG. 6 is an enlarged view of one conductor in FIG. 5, FIG. 7 is an operation explanatory view, and FIG. 8 is also the vicinity of the electrode in the elastic spacer. FIG.

  First, in FIG. 1, the steering wheel 1 has a hub portion 1a in which an air bag module 2 described later is disposed at the center thereof, and three spokes on the lower side and the left and right sides of the hub portion 1a. A portion 1b is formed, and an annular rim portion 1c is supported via three spoke portions 1b.

  As shown in FIG. 2, the airbag module 2 is housed in a cover body 3 formed of resin, and is attached to the upper surface side of the base plate 2a (the back surface side of the cover body 3) via a retainer 2b. The bag 2c and the inflator 2d attached from the lower surface side to the substantially central portion of the base plate 2a are configured.

  The cover body 3 is made of a thermoplastic elastomer (for example, thermoplastic olefin; TPO) by injection molding or the like. The base plate 2a is engaged with a peripheral wall 3c formed on the outer peripheral portion thereof, and caulking and fixing with rivets (not shown) are performed. It is attached by fitting and fixing with a locking band having a frame shape. An attachment piece (not shown) is formed on the base plate 2a and is attached to the hub portion 1a with screws or the like. In addition, it is hated that the stepped portion 3a having a crank shape on the outer peripheral portion and the stepped portion 3a in the back cover (not shown) of the steering wheel 1 and the outer peripheral portion having a complementary crank shape are overlapped so that a gap or the like is not generated largely. It is designed to be attached.

  A decorative body mounting portion 3b is recessed in a substantially central portion of the cover body 3, and an ornament 4 as a decorative body is mounted on the decorative body mounting portion 3b.

  As shown in FIG. 4, the ornament 4 has a substantially circular shape, and a decorative portion 4a such as a CI mark or a trumpet figure is formed on the surface side by integral molding or printing.

  As shown in particular detail in FIG. 3, the back side of the ornament 4 is formed in a substantially flat shape, with a mounting leg 4b protruding from the substantially central portion, and a membrane switch panel on the almost entire surface. The membrane switch panel 5 to be constructed is affixed by using a double-sided adhesive tape or an adhesive, and the mounting leg 4b is inserted and protrudes from a through hole 5b formed at a substantially central portion of the membrane switch panel 5. The membrane switch panel 5 is positioned relative to the ornament 4 by fitting a positioning hole 5c (see FIG. 5) formed at a position spaced outward from the through hole 5b into a positioning projection (not shown) protruding from the back side of the ornament 4. It is done by joining.

  The membrane switch panel 5 is configured by pasting a conductive foil 6 such as copper on the back side of a film-like substrate 5a made of polyester resin having a thickness of about 1 mm by screen printing or the like.

  As shown in FIGS. 5 and 6, the conductive foil 6 is provided on the outer peripheral end side of the membrane switch panel 5 so as to surround the through hole 4 c in the center. The electrode 7 is composed of the negative electrode portion 7b.

  Each of the positive electrode side electrode part 7a and the negative electrode side electrode part 7b has a substantially circular shape with a diameter of about 5 mm in a state where a wide part of both of them has a wavy space, for example, and is respectively formed by a lead wire part 7c. They are electrically connected to each other, and are connected to a horn circuit (not shown) through a metal chip 7d provided at the tip of the lead wire portion 7c. The lead wire portion 7c is accommodated in a groove (not shown) formed along the longitudinal direction of the mounting leg portion 4b (for example, the vertical direction in FIG. 3). It is drawn into the cover main body 3 through the engagement claws.

  In addition, the shape of the positive electrode side electrode part 7a and the negative electrode side electrode part 7b is appropriately selected depending on the size and shape of the ornament 4 and the shape formed by the wide part is appropriately selected such as a circle, a rectangle or a rhombus. can do.

  An engagement protrusion 4c is formed at the tip of the attachment leg 4b of the ornament 4, and the engagement protrusion 4c passes through the attachment hole 3c formed in the decorative body mounting portion 3b of the cover main body 3 so as to decorate the decorative body. The ornament 4 is fixed to the cover body 3 by engaging with a locking member 8 made of nylon 66 resin attached to the back side of the mounting portion 3b.

  Below the membrane switch panel 5, the decorative body mounting portion 3b is provided with an elastic spacer 9 made of silicon rubber by injection molding or the like.

  The elastic spacer 9 has an insertion hole 9a through which the mounting leg 4b is inserted at the center thereof, and extends to the back side of the cover body 3 so as to face the electrode 7 at the outer peripheral end. In addition, a protruding portion 9b having a bottomed cylindrical shape is formed, and a bottom wall portion 9b-1 of the protruding portion 9b is a contact surface on the decorative body mounting portion 3b side.

  The bottom wall portion 9b-1 of the protruding portion 9b accommodates a conductor 10 having a cylindrical shape such as brass in order to electrically connect the positive electrode side electrode portion 7a and the negative electrode side electrode portion 7b of the electrode 7. In addition, the elastic spacer 9 is positioned with respect to the decorative body mounting portion 3b by being inserted into the recessed portion 3b formed in the decorative body mounting portion 3b.

  The side wall 9b-2 of the protruding portion 9b is formed in a thin shape and has a biasing force that can be elastically deformed when the ornament 4 is pressed against the cover body 3, and the biasing force is always present. Thus, the conductor 10 is separated from the positive electrode side electrode portion 7a and the negative electrode side electrode portion 7b.

  Therefore, the membrane switch panel 5 having the electrode 7, the conductor 10 that closes the electrode 7, and the electrode 7 and the conductor 10 that are between the electrode 7 and the conductor 10 are relatively always attached in the opening direction. The elastic spacer 9 energized constitutes an activation switch which is a switch of the horn circuit.

  In the embodiment of the present invention configured as described above, when the ornament 4 is pushed down in the direction of the arrow Z shown in FIG. 7 with respect to the cover body 3 from the state shown in FIG. The bottom wall portion 9b-1 is pressed against the recessed portion 3b-1 of the decorative body mounting portion 3b, and the side wall 9b is bent against the urging force to be crushed.

  As a result, the conductor 10 electrically connects the positive electrode portion 7a and the negative electrode portion 7b, activates the horn circuit, and blows the horn.

  Thus, the operation of crushing the side wall 9b of the projection 9b is performed by pushing down the hard ornament 4, and for example, a stroke of about 2 mm can be secured, so that the projection of the elastic spacer 9 on the electrode 7 can be secured. The operation touch that elastically deforms the portion 9b becomes good, that is, an accurate response is given to the operation performed by the passenger himself.

  In particular, a click feeling is generated by the bottomed cylindrical projection 9b of the elastic spacer 9, and the moment when the conductor 10 conducts the positive electrode side electrode portion 7a and the negative electrode side electrode portion 7b and blows the horn to the occupant. The start switch of the horn circuit which can be easily grasped, does not push the ornament 4 too strongly, and does not inadvertently make a long horn sound, and is well suited to the delicate touch of a so-called greeting horn. .

  Since a plurality of sets of the electrode 7 and the conductor 10 are disposed so as to surround the mounting leg 4b as the center, the ornament 4 is displayed even when the position shifted from the center of the ornament 4 is pushed down. Although it is pushed down in a somewhat tilted state, any of the electrodes 7 and the conductors 10 in a plurality of rows are electrically connected to each other so that a horn can be blown out. be able to.

  Ordinarily, the ornament 4 has a color tone (for example, the cover body 3 is made dark brown with respect to the dark brown), gloss (for example, the cover body 3 of the cover body 3) so that the cover body 3 can be easily identified. Since it is semi-matte and glossy, etc.), the texture (for example, the cover body 3 is leather-like compared to leather-like) is greatly different. The horn sounding operation by pressing such an ornament 4 is intuitively familiar to the occupant, can be directly connected to the operation of the heel, and can be said to be the best horn switch configuration.

  FIG. 9 shows another embodiment of the present invention.

  According to FIG. 9, the membrane switch panel 5 is pasted on the decorative body mounting portion 3 b side of the cover body 3, and the electrode 7 is disposed upward (the ornament 4 side). The elastic spacer 9 is arranged on the ornament 4 side, the cylindrical projection 9b is opened on the decorative body mounting portion 3b side, and the bottom wall portion 9b-1 is a contact surface on the decorative body 4 side. Is different from the above embodiment in that it is configured to face the electrode 7.

  In addition, the membrane switch panel 4 is similar to the above-described embodiment, for example, by forming the electrode 7 by pasting a conductive foil such as copper on a glass mat reinforced epoxy resin panel having a thickness of 1.5 mm by screen printing. In addition, the conductor 10 is disposed in the bottomed cylindrical projection 9b to prevent the conductor 10 from being oxidized by moisture or the like. As a result, a strict anti-oxidation coating is provided. Etc. becomes unnecessary, and the cost can be reduced accordingly.

  FIG. 10 shows a modification of the embodiment shown in FIG.

  According to FIG. 10, the surface of the ornament 4 is plated with a conductive material such as silver so that the ornament 4 includes the conductive film portion 4d including the mounting leg portion 4b. A protrusion is formed on the side so as to face the electrode 7 to form the conductor 10, and the conductor 10 is fitted to the protrusion 9b by passing through the bottom of the bottomed cylindrical protrusion 9b. The point of supporting is different.

  Further, even if the electrodes 7 are separated from each other as in the above embodiment and a large number of electrodes 7 are provided in the ornament 4, the cost is hardly increased, and therefore, the number of the electrodes 7 is substantially accommodated. Only the cost for increasing the number of conductors 10 to be performed is required. If the number of contact groups increases, the probability that the contact is located directly under the place where a light touch is applied by the so-called greeting horn operation increases, or even if it is not located directly below, the distance between the place and the contact is reliably shortened. A direct operational feeling can be obtained at the place where the load is received, and the operability can be improved. This is effective even when the ornament 4 is pressed with a biased pressure, that is, the conductor 10 is located at a position where it is tilted and pushed down, or at least the conductor 10 is located in the immediate vicinity. Therefore, the conductor 10 formed of the protrusion can stably perform the conduction action between the positive electrode side electrode portion 7a and the negative electrode side electrode portion 7b.

  According to the present invention, the switch can be closed by pressing the decorative body against the urging force of the elastic spacer toward the cover body, so that the operator can reliably feel the operation stroke of the decorative body. When the switch is used as a horn switch, it is possible to always obtain a loud sound level suitable for the situation, and to form the decorative body from a hard material, thereby forming an elastic spacer. Switch, such as a horn operation switch, because the spring force of the elastic spacer can be reduced and the opening and closing operation of the membrane switch panel can be performed with a light operational feeling. Can be applied to a suitable airbag device or the like that is mounted on the center portion of the steering wheel in which is installed.

1 is a plan view of a steering wheel according to an embodiment of the present invention. It is AA sectional drawing in FIG. FIG. 3 is an enlarged view within a one-dot chain line circle in FIG. 2. It is a disassembled perspective view of the cover main body assembly in FIG. Similarly, it is a single perspective view of a membrane switch panel. It is the enlarged view which drew one conductor in FIG. It is operation | movement explanatory drawing in embodiment of this invention. It is a partial cross section figure near an electrode in an elastic spacer in an embodiment of the invention. It is an expanded sectional view similar to FIG. 3 in other embodiment concerning this invention. It is an expanded sectional view similar to FIG. 3 in further another embodiment concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steering wheel 2a Air bag 3 Cover main body 3b Decoration body mounting part 3c Attachment hole 4 Ornament (decoration body)
4b Mounting leg 5 Membrane switch panel (membrane switch panel)
7 Electrode 9 Elastic spacer 9b Protrusion 9b-1 Bottom wall (contact surface)
10 Conductor

Claims (4)

An airbag device configured by forming a decorative body mounting portion on a cover main body for storing an airbag, and mounting the decorative body on the decorative body mounting portion so as to be able to advance and retreat, the back surface of the decorative body, the decorative body mounting portion, A switch is disposed between the electrode, the switch, a membrane switch panel having an electrode, a conductor that closes the electrode, and the electrode and the conductor between the electrode and the conductor. An airbag device comprising: an elastic spacer that is relatively normally urged in the opening direction; and the switch is closed by pressing the decorative body toward the cover body. 2. The airbag according to claim 1, wherein the decorative body is attached to the decorative body mounting portion via a central attachment leg, and a plurality of the switches are provided at positions surrounding the attachment leg. apparatus. The airbag device according to claim 1 or 2, wherein a bottomed cylindrical projection is provided on the elastic spacer, and the conductor is disposed on an inner bottom wall of the projection. The airbag device according to claim 1 or 2, wherein the conductor is integrally formed on the back side of the decorative body.

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