Air bag steering wheel with visible spokes

Abstract: The steering wheel includes an external handling rim and a central unit equipped with an air bag device and having radial spokes extending outwards and attached to said handling rim. The central unit (4) consists of two parts (5, 6), of which a lower one (6) shaped as a bowl serving the purpose to accommodate the air bag device (11) and to be attached to the steering column and comprising said radial spokes (8) and a upper one (5) essentially flat and serving the purpose to support a covering element (12) for the air bag device and itself provided with radial spokes (13) extending laterally from said covering element (12) and overlapping and fixed to an inside portion of said radial spokes (8) of the lower part (6).

Description: The present invention consists of a motor vehicle steering wheel equipped with air bag, that provides for visible spokes aimed at conferring a sports appearance to the steering wheel itself. It is now customary use to supply steering wheels with safety devices of the "air bag" type, that allow the driver to avoid catastrophic collisions against the steering wheel and in particular against the steering column, in case of an accident one such steering wheel can be seen in GB-A-2 242 871. On the other hand the presence of an air bag device in the known steering wheels translates into a total covering of the central portion of the wheel, including the spokes, with the result of compromising the steering wheel sports character. This can definitely be disagreeable to the end users to which the steering wheel is addressed. Object of the present invention is to implement a motor vehicle steering wheel equipped with an air bag unit, structured in such a way as to keep part of the spokes in sight in order to maintain a sports appearance though in observance of the required safety conditions. According to the invention this object has been achieved by means of a motor vehicle steering wheel as defined in claim 1. In this way the presence of the air bag device does not compromise the sports appearance of the steering wheel, that is fully maintained by the visible spokes extending between the air bag device and the external handling rim. The characteristics of the present invention will be made even more evident by the following detailed description of some embodiments thereof illustrated as a non-restrictive example in the attached drawings, where: Fig. 1 shows a plan of the steering wheel according to the invention as viewed from above; Fig. 2 shows a section of said steering wheel along the line II-II of Fig. 1; Fig. 3 shows a section of said steering wheel along the line III-III of Fig. 1; Fig. 4 shows a cross section, enlarged in scale, of the handling rim inner metal core of the steering wheel of Figures 1-3; Fig. 5 shows a section view analogous to that of Fig. 2, referring to a variation of the steering wheel in the previous Figures, which is not part of the invention. The steering wheel in Figures 1, 2 and 3 includes a round handling rim 1 consisting of an inner metal core 2 with a constant section and of an external body 3 in wood, polyurethane at sight, polyurethane with leather or other appropriate coating. The steering wheel includes also a central unit 4 made of two overlapping metal parts 5 and 6 fixed one to the other. The lower part 6 is shaped as a bowl with a central base 7 to be attached to the steering column by means of an end hub 27 and three T-shaped external ends 20 radial spokes 8, extending radially and upwards to reach the metal core 2 of the handling rim 1 and to be fastened to it by means of nails or rivets 9, as shown as an example in Figures 1-3; as an alternative, the metal core 2 can be made out of a bent sheet or even as an extruded shape and subsequently bent. As shown more clearly in Fig. 4, the inner metal core 2 of the handling rim 1 consists of a bent metal structural shape having constant section, that provides for an internal throat 17 and an external throat 18. The internal throat 17 serves the purpose to house the T-shape ends 20 of the radial spokes 8 and to this regard it is equipped with two close parallel flanges 21 having constant section, conferring the internal throat 17 a relatively reduced width, just greater than the thickness of the radial spokes 8 T-shape ends 20. The external throat 18 has a greater width and a reduced thickness and provides for two short side flanges 22 having a thickness increasing from the outside to the inside serving the purpose to grant transverse strength to the metal core 2 and therefore to the handling rim 1. The upper part 5 of the central unit 4 is itself essentially flat in shape with a concave central portion 10 designed to accommodate an air bag device schematically indicated with 11, housed inside the concavity of the lower part 6 and fastened to it by means of bolts 28 and covered with a covering element 12 supported by said central concave portion 10. From the latter, portions of the spokes 13 extend laterally overlapped and fastened by means of nails or rivets 14 to an inside portion of the radial spokes 8 of the lower part 6. The invention finally provides for a lower covering 15 with a coating 16 extending from the handling rim 1. The result is a steering wheel with air bag, that provides for visible metal spokes aimed at conferring a sports appearance to the steering wheel itself. The variation in Fig. 5 shows the same structure characteristics of the steering wheel in Figures 1-3, with the exception of the base of the lower part 6 of the central unit 4, designed for direct attachment to the steering column, and of the rim 1 metal core 2, consisting in a reversed U-section made of a casting with said lower part 6.

Claims: Motor vehicle steering wheel including an external handling rim (1) and a central unit (4) with air bag device that has radial spokes extending outwards and attached to said handling rim, said central unit (4) being made of two parts (5, 6), of which a lower one (6) shaped as a bowl serving the purpose to accommodate the air bag device (11) and to be attached to the steering column and comprising radial spokes (8) and an upper one (5) essentially flat which serves the purpose to support a covering element (12) for the air bag device and is provided with radial spokes (13) extending from the sides of said covering element (12) and overlapped and fixed to an inside portion of said radial spokes (8) of the lower part (6), characterised in that said radial spokes (8) of said lower part (6) are provided with integral T-shaped ends (20) housed and fixed in an internal throat (17) of a metal core (2) of the handling rim (1) and said zadial spokes (13) of the upper part (5) extend along the radial spokes (8) of the lower part (6) to the proximity of the handling rim (1). Steering wheel according to claim 1, characterised in that said metal core (2) of the handling rim (1) is made of an extruded shape bent and attached to said radial spokes (8). Steering wheel according to claim 1, characterised in that said metal core (2) of the handling rim (1) is made of a bent metal sheet. Steering wheel according to claim 1, characterised in that said internal throat (17) of said metal core (2) of the handling rim (1) has two parallel flanges (21) which provide the internal throat (17) with a width just greater than the thickness of the T-shaped ends (20) of the radial spokes (8) of said lower part (6). Steering wheel according to claim 1, characterised in that said T-shaped ends (20) of the radial spokes (8) of said lower part (6) are directly attached to the metal core (2) of the handling rim (1).

Inventors: CATTANEO MARCO, CATTANEO, MARCO
Applicants: BREED AUTOMOTIVE TECH, BREED AUTOMOTIVE TECHNOLOGY, INC.
Application year: 1997
Main classification: B60R21
IPC codes: B62D1, B60R21