MXPA97004639A - Lamina steering wheel - Google Patents

Abstract

The present invention relates to the skeleton of a steering wheel comprising a hub, spokes, and a flange wherein the skeleton consists of a single piece made of a single sheet steel preform, by separation and bending without machining, and where the cube has a tubular shape and is formed with a double-layer structure having two layers that makes contact between

Description

METAL SHEATH STEERING WHEEL DESCRIPTION OF THE INVENTION The present invention relates to a skeleton of a steering wheel with a hub, spokes, and a rim. The skeletons of the steering wheels of this type, usually are formed of several parts fastened together by rivets, screws, solid, welding or a combination thereof, and then finished by extruding plastic around them or covering them with a material of leather or a similar material. The skeleton constitutes the support structure and must be designed strong enough to withstand the forces exerted on the steering mechanism by the driver. An increasing number of extra functions should also be taken into account when designing such a skeleton. At least both of a conventionally accessible mechanism for driving the horn and an airbag, for example, must be housed in the steering wheel. More and more switches and buttons for various vehicle functions must also be mounted directly on the steering wheel, where the driver can operate them without having to remove their hands from it. Finally, the steering wheel skeleton must be designed to ensure passive safety, which means that it should not cause severe injuries in the event of an accident. For this reason, in particular, contemporary steering wheels are more or less in the shape of a cup or bowl, with the outer rim facing the driver and the hub farthest forward and with the spokes consequently, bending inward and toward outside towards the cube. It should be obvious from the above, that all these demands can be better met with a compound steering wheel, allowing all the opposite requirements to a certain extent, to be achieved simultaneously. On the other hand, there have always been attempts to make manufacturing costs as reasonable as possible, which is increasingly important for traditional car manufacturers, due to the growth in international competition. Accordingly, there has been no lack of attempt to build yet such complicated steering wheels from as few parts as possible. Known from U.S. Patent 4,359,911, for example, there is a steering wheel skeleton with a central mount comprising a hub and spokes stamped out of the metal sheet and with a separate rim enclosed by and riveted to the ends of the wheel. the rays. The central assembly and the flange can be made of different materials, allowing the specific demands made of each part that will be fulfilled independently. Still, the clamping method is comparatively complicated. It is known from German Patent 3 719 658 Al there is a steering wheel made of a sheet of metal and comprising an outer metal blade bowl facing the driver and a metal sheet bowl transmitting force fastened behind the wheel. He with a space left between them, which comprises the rim. Non-radial rays such as are involved, and general assembly looks like a disk, when viewed with the head raised. This approach is intended to save weight, simplify manufacturing and improve safety, in that the rear bowl can deform and hermetically enclose a volume of air to specific cross-sections of flow. The bowls are held together air tight along their circumferences, that is, the vicinity of the flange. This known steering wheel consists, apart from an insert in the hub, of only two components and therefore, relatively simple to manufacture. However, it is not economically satisfactory, because the fingers can not fit very far around the rim. In addition, such additional components as switches, buttons, etc., would significantly compromise its airtightness. Finally, the purpose of the interior filled with air today can be achieved much more effectively with an integrated airbag, an airbag, however, it could not be used on such a steering wheel without sacrificing its basic concept. Accordingly, there is a need for a steering wheel of the type described so far, which could be even less expensive to manufacture, but would be subject to any of the design limitations with respect to the demands mentioned in the foregoing, while still allowing the adjustment of the additional functions mentioned in the above. This object is achieved according to the present invention in the skeleton of a one-piece steering wheel, made of a single sheet metal preform, finished by separation and molding without machining. The present invention is based on the knowledge that a steering wheel skeleton can be manufactured in one piece, including the flange exploiting the full potential for cutting and drilling a sheet metal preform without or with significant sacrifice of yet a requirement with Regarding resistance, form, or additional functions. The machining and steps that provide the unmachined shape can be mutually adjusted according to the final prescribed shape of the steering wheel skeleton, so that virtually any desired final shape can be achieved. The blade does not need to be too thick and the skeleton does not need to be left with excess material. The skeleton of the steering wheel obtains its final form in a practical form, by a sequence of several molding stages which are in principle known from the technique of working a sheet of metal and preferably combined with one or more separation stages. From another aspect of the theory behind the present invention, the spokes can be constructed in accordance with the principle of a support of equal transverse strength. It is also possible to use cold material that holds in a molding process without machining, accompanied by duplication of local material for reinforcement (for example, the bucket). Other modifications and embodiments are cited in Claims 7 to 10. Figure 1 is a section through a steering wheel frame 1 in accordance with the present invention and Figure 2 is a section through a lightning mode. . The preform 5 of the steering wheel illustrated in Figure 1 has a hub 2 with two layers 10 of material to make it coarse and sufficiently rigid to accept spline or machining. The spokes 3 extend upwards and outwards with left steps to adapt such accessories as a particular airbag. Since the spokes 3 and a flange 4 are U-shaped in section, the dimensions of the section can be varied to provide the preform of the steel sheet 5 with sufficient strength without varying its thickness. The assembly has been facilitated by providing the hub 2 with a cone 6. One of the steps can be provided with an unthreaded hole 7, a separate cut 8 with a nut 11 embedded in it (as illustrated) or a threaded hole 9. As will be evident from the illustration, the skeleton of the steering wheel has essentially been shaped by stamping, punching and bending parallel to its axis, which means that all the tools in the production line are oriented in the same direction. This considerably simplifies fabrication, and relatively complicated sheet metal shapes can be rationally produced. The actual form can, of course, be varied to conform to different requirements without implying any other manufacturing principle. This does not mean, however, that processing in other orientations can not be included for specific purposes. The outer edge of the flange 4 or the edge on the right side of the center 12 may be rolled inwardly, for example.

Figure 2 is a section through a mode of a ray 3. The ray 3 has been provided with extra rigidity and protected from damage by stamping and bending from its edges 10 outwards. Accordingly, it is possible to adjust the essentially separate edges of the static or dynamic tension. The curvature of the base 11 of the section allows the additional anti-deformation hardening there. There is also more space left to adjust the outer layers of the steering wheel. The main advantage of both modalities is that the skeleton of the steering wheel can be produced in a piece of a single sheet metal preform. The final product will therefore be homogeneous and satisfy all the requirements. You will not have meetings that may lead to failure and require extra inspection.

Claims (10)

1. The skeleton of the steering wheel with a hub, spokes, and rim, characterized in that the skeleton is made of a piece of a preform of a single sheet of steel, provided with its final shape by separation and bending without machining.

2. The skeleton of the steering wheel according to claim 1, characterized in that the skeleton has been provided with its final shape by a sequence of bending operations.

3. The skeleton of the steering wheel according to claim 1 or 2, characterized in that the skeleton has been provided with its final shape, by one or more separation operations combined with bending and without machining.

4. The skeleton of the steering wheel according to one of claims 1 to 3, characterized in that the spokes are in the form of poles of equal transverse strength.

5. The skeleton of the steering wheel according to one of claims 1 to 4, characterized in that some areas of the skeleton have been reinforced by the use of hardening by deformation of cold material.

6. The skeleton of the steering wheel according to one of claims 1 to 5, characterized in that some areas of the skeleton have been reinforced using two layers of the material.

7. The skeleton of the steering wheel according to one of claims 1 to 6, characterized in that the skeleton is made of a preform of a steel sheet of 1 to 3 mm in thickness.

8. The skeleton of the steering wheel according to claim 7, characterized in that the spokes are U-shaped in section with their edges bent outwards and their base curved inwards in section.

9. The skeleton of the steering wheel according to one of claims 1 to 8, characterized in that the skeleton hub is provided with a cone facing the vehicle and at an angle of at least 3 °.

10. The skeleton of the steering wheel according to one of claims 1 to 9, characterized in that the separation incision also comprises the creation of unthreaded holes, separate cuts, or threaded holes for attaching an air pocket thereto.