STEERING WHEEL ASSEMBLY WITH AIRBAG

Abstract

A steering wheel assembly includes a steering wheel base containing a plurality of detents, an electric horn circuit extending along the steering wheel base and electrically connected to a vehicle horn, and an airbag assembly containing a plurality of hooks arranged to engage with each of the detents. The electric horn circuit includes a plurality of slots across each of the detents. Each hook includes an electrical connector positioned to close the respective slot when the hook is fully engaged with the respective detents and to leave the respective slot open when the hook is not engaged with the respective detents. The electric horn circuit is lockable to activate the vehicle horn when the electrical connectors close the slots.The electrical horn circuit is open if at least one of the electrical connectors does not close the respective gap.

Description

AREA OF TECHNOLOGY

[0001] This disclosure concerns a steering wheel assembly in vehicles. GENERAL STATE OF THE ART

[0002] Vehicles are equipped with airbags. In the event of a certain impact, one or more gas generators activate one or more airbags, providing them with an inflation medium. The airbags are then pressurized and control the occupants' movement. The airbags are located in various positions within the passenger compartment of vehicles. Vehicles typically include a driver's airbag, mounted in the steering wheel; a passenger airbag, mounted in the dashboard on the opposite side of the vehicle from the driver's airbag; and side curtain airbags, mounted above the side windows. SUMMARY

[0003] This document discloses a steering wheel assembly for a vehicle. The steering wheel assembly includes a steering wheel base containing a plurality of detents, an electric horn circuit extending along the steering wheel base and electrically connected to a vehicle horn, and an airbag assembly containing a plurality of hooks arranged to engage each of the detents. The electric horn circuit includes a plurality of slots across each of the detents. Each hook includes an electrical connector positioned to close the respective slot when the hook is fully engaged with the respective detents and to leave the respective slot open when the hook is not engaged with the respective detents. The electric horn circuit is lockable to activate the vehicle horn when the electrical connectors close the slots.The electrical horn circuit is open if at least one of the electrical connectors does not close the respective gap.

[0004] The design of this steering wheel assembly facilitates its manufacturability. During assembly, a technician can activate the horn (e.g., by pressing on the airbag assembly) while installing the airbag assembly into the steering wheel base. A sound from the vehicle horn indicates that all hooks are fully engaged with their respective detents. If the vehicle horn does not sound, the technician is alerted to a potential problem and can investigate whether one of the hooks is not fully engaged or if another issue is affecting the vehicle horn or the electrical horn circuit. Furthermore, the design ensures simple and predictable behavior during installation.The design does not use multiple stages; each hook is either fully engaged, in which case the electrical connector closes the respective gap and allows the vehicle horn to function, or it is not fully engaged, in which case the gap is open and the vehicle horn does not make a sound.

[0005] A steering wheel assembly includes a steering wheel base containing a plurality of detents, an electric horn circuit extending along the steering wheel base and electrically connected to a vehicle horn, and an airbag assembly containing a plurality of hooks arranged to engage with each of the detents. The electric horn circuit includes a plurality of slots across each of the detents. Each hook includes an electrical connector positioned to close the respective slot when the hook is fully engaged with the respective detents and to leave the respective slot open when the hook is not engaged with the respective detents. The electric horn circuit is lockable to activate the vehicle horn when the electrical connectors close the slots.The electrical horn circuit is open if at least one of the electrical connectors does not close the respective gap.

[0006] In one example, the electrical connectors can be metal plates, each extending across the respective outer surfaces of the respective hooks. In another example, each hook can include a bottom surface facing a frame section of the airbag assembly, the bottom surfaces being able to contact the respective latches when the respective hooks are fully engaged, and the electrical connectors being able to be positioned on the respective bottom surfaces. In yet another example, each latch being able to include a contact surface that contacts the respective bottom surface when the respective hook is fully engaged, and the contact surfaces being non-conductive.

[0007] In one example, the columns in the electric horn circuit can be arranged in series.

[0008] In one example, each gap can contain a first cable lug end and a second cable lug end spaced apart from the first cable lug end, and the respective electrical connector can touch the first cable lug end and the second cable lug end of the respective gap when the respective hook is fully engaged.

[0009] In one example, the electric horn circuit can include an electric switch that can be closed by pushing an outer casing of the airbag assembly towards the steering wheel base. In another example, the steering wheel assembly can further include a spring that biases the outer casing of the airbag assembly away from the steering wheel base at the electric switch.

[0010] In another example, the airbag assembly can include a frame section and the outer shell, and the hooks are rigidly connected to the frame section.

[0011] In another example, the electrical switch in the electric horn circuit can be arranged with the columns in series.

[0012] In another example, the electric horn circuit can include a plurality of electric switches, including the electric switch itself, each of which can be closed by pressing the outer casing towards the base of the steering wheel. In yet another example, the electric switches in the electric horn circuit can be arranged in parallel. In yet another example, the parallel arrangement of the electric switches in the electric horn circuit can be arranged with the columns in series.

[0013] In one example, the hooks can run parallel to each other along an elongated length. In another example, the hooks can define respective longitudinal axes, and each hook can include a bottom surface facing a frame section of the airbag assembly along its respective longitudinal axis. These bottom surfaces can contact the respective detents when the respective hooks are fully engaged. In yet another example, the electrical connectors can be positioned on the respective bottom surfaces.

[0014] In one example, the airbag assembly may include an airbag cushion and a gas generator positioned to inflate the airbag cushion. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic top view of an exemplary vehicle that includes an exemplary steering wheel assembly. Fig. Figure 2 is a perspective side view of the steering wheel assembly. Fig. Figure 3 is a schematic cross-sectional view from above of an airbag assembly of the steering wheel assembly. Fig. Figure 4 is a top view of a steering wheel base of the steering wheel assembly. Fig. Figure 5 is a circuit diagram of an exemplary electric horn circuit of the steering wheel assembly. Fig. Figure 6 is a perspective view of a hook of the steering wheel assembly. Fig. Figure 7 is a perspective view of a ratchet of the steering wheel assembly. Fig. Figure 8 is a cross-sectional view of the hook fully engaged with the latch. Fig. Figure 9 is a flowchart of an exemplary process for assembling the steering wheel assembly. DETAILED DESCRIPTION

[0015] With reference to the figures, in which the same reference numerals denote the same parts in the different views, a steering wheel assembly 105 comprises a steering wheel base 110 incorporating a plurality of detents 410, an electric horn circuit 115 extending along the steering wheel base 110 and electrically connected to a vehicle horn 120, and an airbag assembly 125 comprising a plurality of hooks 340 arranged to engage each of the detents 410. The electric horn circuit 115 comprises a plurality of columns 415 over each of the detents 410. Each hook 340 includes an electrical connector 505 positioned to close the respective column 415 when the hook 340 is fully engaged with the respective detents 410, and to leave the respective column 415 open when the hook 340 is not engaged with the respective detents 410.The electric horn circuit 115 can be closed to activate the vehicle horn 120 when the electrical connectors 505 close the gap 415. The electric horn circuit 115 is open when at least one of the electrical connectors 505 does not close the respective gap 415.

[0016] With reference to Fig. 1 includes a vehicle 100 and the steering wheel assembly 105. The vehicle 100 can be any passenger or commercial vehicle, such as a car, truck, SUV, crossover, van, minivan, taxi, bus, etc.

[0017] The vehicle 100 includes the vehicle horn 120. The vehicle horn 120 is a sound-generating device that generally produces a "honk" or "beep" sound directed outwards from the vehicle 100. An operator of the vehicle 100 can use the horn to indicate to other road users that the vehicle 100 is present or to notify other road users of a circumstance. The vehicle horn 120 may be located at a front end of the vehicle 100. The vehicle horn 120 may be spaced apart from the steering wheel assembly 105.

[0018] The vehicle 100 includes a steering system 130. The steering system 130 is typically a conventional subsystem for steering a vehicle and controls the steering of the wheels. The steering system 130 can be a rack and pinion system with electric power steering, a steer-by-wire system, as both are known, or any other suitable system. A human operator can control the steering system 130 via the steering wheel assembly 105.

[0019] The vehicle 100 (e.g., the steering system 130) includes the steering wheel assembly 105. The steering wheel assembly 105 includes the steering wheel base 110 and the airbag assembly 125. The steering wheel base 110 is fixed to a steering column 135 of the steering system 130, and rotation of the steering wheel base 110 rotates the steering column 135 and steers the wheels of the vehicle 100. The airbag assembly 125 is clamped to the steering wheel base 110, as described in more detail below. Once the airbag assembly 125 has been attached to the steering wheel base 110 during assembly, the steering wheel base 110 and the airbag assembly 125 rotate together as a unit about an axis of rotation R defined by the steering column 135.

[0020] The electric horn circuit 115 extends along the steering wheel base 110, as described in more detail below. The position of the electric horn circuit 115 allows an operator of the vehicle 100 to easily operate the vehicle horn 120. The electric horn circuit 115 is electrically connected to the vehicle horn 120. The electric horn circuit 115 can be electrically connected to the vehicle horn 120, for example, by a wire 140 extending from the steering wheel base 110 to the vehicle horn 120.

[0021] With reference to Fig. 2 includes the steering wheel assembly 105, the steering wheel base 110, and the airbag assembly 125. The steering wheel base 110 includes a hub 205 and a ring 210 that extends circumferentially around the hub 205. The hub 205 can be connected to the steering column 135 (in Fig. (1 shown) are connected. The ring 210 can be fixedly attached to the hub 205. The ring 210 can have a generally toroidal shape that can be grasped by the operator to rotate the steering wheel assembly 105 about the axis of rotation R.

[0022] The airbag assembly 125 can be clamped to a rear side of the steering wheel base 110 (i.e., a side of the steering wheel base 110 facing the operator). The airbag assembly 125 can be clamped to the hub 205 of the steering wheel assembly 105. The airbag assembly 125 can present a finished surface towards the operator.

[0023] With reference to Fig. 3 The airbag assembly 125 can include a frame section 305, an outer shell 310, an airbag cushion 315, a gas generator 320, springs 325 and the hooks 340.

[0024] The frame section 305 can serve as a base or platform for mounting the airbag cushion 315 and the gas generator 320. Once the airbag assembly 125 is installed, the frame section 305 can be positioned relative to the steering wheel base 110 (in Fig. (2 shown) are fixed. The frame section 305 provides a rearward-facing surface against which the airbag cushion 315 can press during inflation to inflate in a backward direction (i.e., towards the operator).

[0025] The airbag cushion 315 is inflatable from a deflated to an inflated position. In the deflated position, the airbag cushion 315 can be enclosed between the frame section 305 and the outer cover 310. In the deflated position, the airbag cushion 315 can be folded and resting on the frame section 305. The airbag cushion 315 can be made of any suitable airbag material, such as a polymer fabric. For example, the airbag cushion 315 can be made of a woven nylon yarn, such as nylon 6-6. Other suitable examples include polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyester, or any other suitable polymer. The polymer fabric can include a coating, such as silicone, neoprene, urethane, and so on. For example, the coating can be polyorganosiloxane.

[0026] The gas generator 320 is positioned to inflate the airbag cushion 315. The gas generator 320 is fluidly connected to the airbag cushion 315. The gas generator 320 can be mounted on the frame section 305. Upon receiving a signal, for example from a vehicle control unit, the gas generator 320 can inflate the airbag cushion 315 with an inflation medium, such as a gas. The gas generator 320 can, for example, be a pyrotechnic gas generator that uses a chemical reaction to introduce an inflation medium into the airbag cushion 315. The gas generator 320 can be of any suitable type, for example, a cold gas generator.

[0027] The outer shell 310 extends around and covers the airbag cushion 315 in the uninflated position. The outer shell 310 may include seams or the like (not shown) that open when the airbag cushion 315 presses against an inner surface of the outer shell 310 during inflation. The outer shell 310 may present a finished outer surface to the operator, and the operator may activate the vehicle horn 120 by pushing the outer surface of the outer shell 310 toward the steering wheel base 110 (i.e., in a forward direction), as described below. The outer shell 310 may be movable along an axis within a range of motion toward and away from the frame section 305 (e.g., along the axis of rotation R).

[0028] The outer shell 310 can include pins 330 positioned in corresponding holes 335 of the frame section 305. The outer shell 310 can move within its range of motion over the pins 330, which slide within the holes 335. The positioning of the pins 330 within the holes 335 can restrict the movement of the outer shell 310 relative to the frame section 305 in directions other than along the axis (e.g., the axis of rotation R). The pins 330 can be positioned to press on respective electrical switches 405 to activate the vehicle horn 120 (described below in relation to Fig. 4 described).

[0029] The springs 325 are positioned to hold the outer casing 310 to the respective electrical switches 405 (in Fig. (4 shown) to preload the springs away from the steering wheel base 110. For example, the springs 325 can be positioned on the respective pins 330, with one end attached to the pin 330 and one end fixed relative to the steering wheel base 110 (e.g., attached to the frame section 305). Pressing the outer sleeve 310, such that one of the pins 330 presses the respective electrical switch 405, can move the end of the respective spring 325 connected to the pin 330, thereby placing the spring 325 into a state of compression or tension. Releasing the outer sleeve 310 allows the spring 325 to move from the state of compression or tension to a relaxed state (or closer to the relaxed state) by moving the outer sleeve 310 away from the steering wheel base 110.

[0030] The airbag assembly 125 includes the hooks 340. The hooks 340 are rigidly connected to the frame section 305. For example, the hooks 340 may be integral with the frame section 305. For the purposes of this disclosure, "integral" is defined as manufactured from a single, uniform piece of material that is not held together by seams, joints, fasteners, or adhesives. The hooks 340 extend longitudinally parallel to one another. In other words, each hook 340 defines a longitudinal axis L along which the hook 340 is elongated. The longitudinal axis L extends along a direction in which the hook 340 moves when it is installed. The longitudinal axes L may be parallel to the axis of rotation R. The shape of the hooks 340 is described below with respect to Fig. 6 described in more detail. The hooks 340 are arranged to engage each of the detents 410 (in Fig. 4 shown) to engage. For example, each hook 340 can be aligned on a respective one of the latches 410 in a plane perpendicular to (i.e. normal to) the longitudinal extension axes L defined by the hooks 340.

[0031] With reference to Fig. 4 The steering wheel base 110 (e.g., the hub 205) includes the detents 410. The detents 410 can be recesses extending into the hub 205. The detents 410 extend into the hub 205 in a vehicle forward direction, parallel to the longitudinal extension axes L defined by the hooks 340 (when the airbag assembly 125 is installed). The detents 410 are shaped to receive and engage the respective hooks 340, as described below with reference to Fig. 7 is described.

[0032] The electric horn circuit 115 extends along the steering wheel base 110. For example, the electric horn circuit 115 can include a variety of wires 420 that connect the electrical components of the electric horn circuit 115. The wires 420 can be clamped in the correct position on a rear surface of the hub 205 of the steering wheel base 110 (i.e., on the surface facing the airbag assembly 125 when installed). The electric horn circuit 115 includes the column 415 and the electrical switches 405.

[0033] The electric horn circuit 115 includes the gap 415 via each of the detents 410. Each gap 415 is an open circuit in the electric horn circuit 115. The electric horn circuit 115 is open at the gap 415 unless something electrically bridges the gap 415. As described below, one of the hooks 340, which fully engages the respective detent 410, bridges the respective gap 415, thereby closing the electric horn circuit 115 at that gap 415. Each gap 415 includes a first cable lug end 425 and a second cable lug end 430, which is spaced apart from the first cable lug end 425. The wire 420, which leads to the gap 415 on one side, ends at the first cable lug end 425 and the wire 420, which leads to this gap 415 on the other side, ends at the second cable lug end 430.Each gap 415 can be closed by an electrical connection from the first cable lug end 425 to the second cable lug end 430.

[0034] The electric horn circuit 115 includes at least one electric switch 405 (e.g., a plurality of electric switches 405) which is activated by pressing the outer casing 310 of the airbag assembly 125 (in Fig. 3 shown) can be closed in the direction of the steering wheel base 110. For example, each electrical switch 405 can be closed under a respective pin 330 (in Fig. (as shown in Figure 3). Each electrical switch 405 can be biased into an open position. When the outer casing 310 is pressed, one of the pins 330 presses on the respective electrical switch 405, thereby moving the electrical switch 405 into a closed position. When the outer casing 310 is released, the bias of the electrical switch 405 causes the electrical switch 405 to move back to the open position.

[0035] With reference to Fig. In section 5, the electric horn circuit 115 is arranged to switch the vehicle horn 120 on and off. The electric horn circuit 115 is electrically connected to the vehicle horn 120 and a battery 510 of the vehicle 100. The battery 510, the vehicle horn 120, and the electric horn circuit 115 can be electrically connected in series. The path for current from the battery 510 leads through both the vehicle horn 120 and the electric horn circuit 115 to reach a ground 515. Thus, in response to the electric horn circuit 115 being closed, current can flow from the battery 510 to the vehicle horn 120, and in response to the electric horn circuit 115 being open, the flow of current from the battery 510 to the vehicle horn 120 is stopped. The electric horn circuit 115 is open if at least one of the electrical connectors 505 does not close the respective gap 415.The electric horn circuit 115 can be closed to activate the vehicle horn 120 (e.g. by pressing the outer casing 310 to close one of the electric switches 405) when the electric connectors 505 close the column 415.

[0036] The battery 510 can be any type suitable for vehicle electrification, for example, lithium-ion batteries, nickel-metal hydride batteries, lead-acid batteries, or ultracapacitors, such as those used in vehicles with internal combustion engines (ICE), plug-in hybrid electric vehicles (PHEVs), hybrid electric vehicles (HEVs), or battery electric vehicles (BEVs). The electric horn circuit 115 includes the electric switches 405. The electric switches 405 are arranged in parallel to each other in the electric horn circuit 115 (that is, the ends of each electric switch 405 are connected to the same two nodes). Thus, when any of the electric switches 405 is closed (e.g.,By pressing the outer casing 310 (as described above), the electric horn circuit 115 is closed via all of the electric switches 405. When the column 415 is closed by the electrical connectors 505, closing any of the electric switches 405 closes the electric horn circuit 115 and activates the vehicle horn 120.

[0037] As described below, each hook 340 includes a respective electrical connector 505, which is positioned to close the respective gap 415 when the hook 340 is fully engaged with the respective detent 410, and to leave the respective gap 415 open when the hook 340 is not engaged with the respective detent 410. Each electrical connector 505 closes the respective gap 415 by electrically connecting the first cable lug end 425 to the second cable lug end 430.

[0038] The columns 415 are arranged in series in the electric horn circuit 115. Thus, the electric horn circuit 115 as a whole is open when any one of the columns 415 is open (e.g., by the hook 340 not fully engaging the respective latch 410). When all columns 415 are closed (by all hooks 340 fully engaging the respective latches 410), the electric horn circuit 115 is closed across all columns 415 and can be closed as a whole by closing it via the electric switches 405.

[0039] Each electrical switch 405 can be arranged in series with the columns 415 in the electrical horn circuit 115. The electrical switches 405 can also be arranged in parallel with the columns 415 in the electrical horn circuit 115. Thus, the electrical horn circuit 115 is closed when at least one of the electrical switches 405 and all columns 415 are closed, and is otherwise open. In other words, the vehicle horn 120 can be switched on by closing one of the electrical switches 405 when all columns 415 are closed. If at least one column 415 is open, the vehicle horn 120 cannot be switched on by closing the electrical switches 405.

[0040] With reference to Fig. Each hook 340 comprises a body section 605 and a hook section 610. The body section 605 can be elongated along its respective longitudinal axis L. The hook section 610 can be positioned at one end of the body section 605 along the longitudinal axis L. The body section 605 and the hook section 610 can be formed in one piece.

[0041] The hook section 610 can be shaped to hold the airbag assembly 125 to the frame section 305 once it is fully engaged with the catch 410. The hook section 610 can extend transversely to the longitudinal axis L of the body section 605. Each hook 340 (e.g., each hook section 610) can include a bottom surface 615 facing the frame section 305 of the airbag assembly 125 along the longitudinal axis L. The bottom surface 615 can form a right angle or an acute angle with the longitudinal axis L in the rearward direction of the vehicle, which can serve to hold the hook 340 in the correct position once it is fully engaged with the catch 410. An upper surface 620 of the hook section 610 can be inclined from the longitudinal extension axis L in the direction of the frame section 305, which can serve to bend the hook 340 to slide over the catch 410 during installation.

[0042] Each hook 340 includes a corresponding electrical connector 505, positioned to close the respective gap 415 when the hook 340 is fully engaged with the respective detent 410, and to leave the respective gap 415 open when the hook 340 is not engaged with the respective detent 410. The electrical connectors 505 are positioned on the respective underside surfaces 615 of the respective hooks 340. The electrical connectors 505 can be metal plates extending over the respective outer surfaces of the respective hooks 340 (e.g., over the respective underside surfaces 615 of the respective hooks 340). For example, the electrical connectors 505 can be embedded in the underside surfaces 615 or overmolded onto the underside surfaces 615.The hooks 340 cannot be conductive on surfaces other than the bottom surfaces 615, so the column 415 can only be closed by placing the bottom surfaces 615 in the correct position.

[0043] With reference to Fig. Each notch 410 can include a tunnel 705 and a contact surface 710. The tunnel 705 is shaped to allow the hook section 610 to pass through it during installation. The contact surface 710 extends transversely to the tunnel 705 at a vehicle-forward end of the tunnel 705. The contact surface 710 touches the respective underside surface 615 when the respective hook 340 is fully engaged (as in Fig. 8 shown). The contact surface 710 can be oriented to coincide with the respective underside surface 615 (e.g. at a right angle or an acute angle relative to the longitudinal axis L in the reverse direction of the vehicle), which can hold the hook 340 in the correct position once it is fully engaged.

[0044] The contact surfaces 710 are non-conductive. The slots 415 in the electric horn circuit 115 can extend across the respective contact surfaces 710. Each slot 415 contains the first terminal 425 and the second terminal 430, which is spaced apart from the first terminal 425. For example, the first terminal 425 and the second terminal 430 can be positioned on opposite sides of the respective contact surface 710. Since the contact surface 710 is non-conductive, the first terminal 425 and the second terminal 430 are not electrically connected unless something conductive touches both the first terminal 425 and the second terminal 430.

[0045] With reference to Fig. 8. The underside surface 615 of the hook 340 contacts the detent 410 (e.g., the contact surface 710 of the detent 410) when the hook 340 is fully engaged with the detent 410. The electrical connector 505 is positioned such that it closes the gap 415 when the hook 340 is fully engaged with the detent 410. By being positioned on the underside surface 615, the electrical connector 505 contacts the first terminal 425 and the second terminal 430 of the gap 415 on each side of the contact surface 710, thus electrically bridging the gap 415 when the hook 340 is fully engaged with the detent 410.

[0046] The electrical connector 505 is positioned such that it leaves the gap 415 open when the hook 340 is not engaged with the respective detent 410. When the underside surface 615 of the hook 340 does not touch the contact surface 710, the electrical connector 505 is spaced on its underside surface 615 from the first cable lug 425 and / or the second cable lug 430. For example, if the hook section 610, and thus its underside surface 615, is still in the tunnel 705 and has not yet moved over the contact surface 710, the electrical connector 505 does not touch the first cable lug 425 or the second cable lug 430, and the gap 415 remains open.

[0047] Fig.Figure 9 is a flowchart illustrating an example of Process 900 for assembling the steering wheel assembly 105. Process 900 can be performed, for example, by one or more technicians in a production facility. The steps of Process 900 can be performed by the same technician or by different technicians. As a general overview of Process 900, a technician installs the airbag assembly 125 onto the steering wheel base 110, and another technician attempts to activate the vehicle horn 120. Upon hearing the vehicle horn 120 sound, a technician proceeds to the next assembly step. Upon hearing the vehicle horn 120 not sound, a technician investigates the cause of the vehicle horn 120's silence.

[0048] Process 900 begins in block 905, where a technician installs the airbag assembly 125 on the steering wheel base 110. The technician aligns the hooks 340 with the respective detents 410 and pushes the airbag assembly 125 in a vehicle forward direction along the longitudinal extension axes L of the hooks 340 toward the steering wheel base 110 until the technician believes that the hooks 340 are fully engaged with the respective detents 410.

[0049] Next, a technician in block 910 presses the airbag assembly 125 to activate the vehicle horn 120 and listens for the sound of the horn. The technician then determines in decision block 915 whether the vehicle horn 120 sounded in block 910. If the vehicle horn 120 sounded, process 900 proceeds to block 920. If the vehicle horn 120 did not sound, process 900 proceeds to block 925. In block 920, a technician moves the steering wheel assembly 105 to the next assembly step. For example, the vehicle 100 might move to the next station on an assembly line. After block 920, process 900 ends.

[0050] In Block 925, a technician determines a cause for the vehicle horn 120 not sounding. The technician may perform a visual inspection to ensure that each hook 340 is fully engaged with each detent 410. The technician may again attempt to engage each hook 340 with its respective detent 410 and again attempt to activate the vehicle horn 120. The technician may remove the airbag assembly 125 and inspect the electrical horn circuit 115. The technician may inspect the wiring 140 to the vehicle horn 120 and the vehicle horn 120 itself. After Block 925, Process 900 ends.

[0051] The revelation has been described in an illustrative manner, and it is understood that the terminology used is intended to be descriptive and not restrictive. The adjectives "first" and "second" are used throughout the Scripture as identifiers and are not meant to indicate meaning, order, or quantity. Expressions such as "front," "forward," "alongside," "back," "behind," "left," "right," "across," "upward," "downward," "vertical," etc., are understood in relation to Vehicle 100. The use of "in response to" and "in determining," etc., indicates a causal relationship, not merely a temporal one. In light of the foregoing teachings, many modifications and variations of the present revelation are possible, and the revelation may be implemented differently than specifically described.

[0052] According to the present invention, a steering wheel assembly is provided comprising: a steering wheel base including a plurality of detents; an electric horn circuit extending along the steering wheel base and electrically connected to a vehicle horn; and an airbag assembly including a plurality of hooks arranged to engage each of the detents; wherein the electric horn circuit includes a plurality of slots over each of the detents; wherein each hook includes an electrical connector positioned to close the respective slot when the hook is fully engaged with the respective detents and to leave the respective slot open when the hook is not engaged with the respective detents; wherein the electric horn circuit is lockable to activate the vehicle horn when the electrical connectors close the slots;and wherein the electrical horn circuit is open if at least one of the electrical connectors does not close the respective gap.

[0053] According to one embodiment, the electrical connectors are metal plates that each extend over the respective outer surfaces of the respective hooks.

[0054] According to one embodiment: each hook includes a bottom surface facing a frame section of the airbag assembly; the bottom surfaces contact the respective detents when the respective hooks are fully engaged; and the electrical connectors are positioned on the respective bottom surfaces.

[0055] According to one embodiment: each latch includes a contact surface that touches the respective underside surface when the respective hook is fully engaged; and the contact surfaces are non-conductive.

[0056] According to one embodiment, the columns in the electric horn circuit are arranged in series.

[0057] According to one embodiment: each gap includes a first cable lug end and a second cable lug end spaced apart from the first cable lug end; and the respective electrical connector touches the first cable lug end and the second cable lug end of the respective gap when the respective hook is fully engaged.

[0058] According to one embodiment, the electric horn circuit includes an electric switch that can be closed by pressing an outer casing of the airbag assembly towards the steering wheel base.

[0059] According to one embodiment, the invention is further characterized by a spring that pre-tensions the outer shell of the airbag assembly away from the steering wheel base at the electrical switch.

[0060] According to one embodiment, the airbag assembly includes a frame section and the outer shell, and the hooks are rigidly connected to the frame section.

[0061] According to one embodiment, the electrical switch in the electrical horn circuit is arranged in series with the columns.

[0062] According to one embodiment, the electric horn circuit includes a plurality of electric switches, including the electric switch, wherein each electric switch can be closed by pressing the outer casing towards the steering wheel base.

[0063] According to one embodiment, the electrical switches in the electric horn circuit are arranged in parallel with each other.

[0064] According to one embodiment, the parallel arrangement of the electrical switches in the electrical horn circuit is arranged with the columns in series.

[0065] According to one embodiment, the hooks are elongated and parallel to each other.

[0066] According to one embodiment: the hooks define respective longitudinal extension axes; each hook includes a bottom surface facing a frame section of the airbag assembly along the respective longitudinal extension axis; and the bottom surfaces contact the respective detents when the respective hooks are fully engaged.

[0067] According to one embodiment, the electrical connectors are positioned on the respective underside surfaces.

[0068] According to one embodiment, the airbag assembly includes an airbag cushion and a gas generator positioned to inflate the airbag cushion.

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