Vehicle steering device

[0002] The invention relates to a vehicle steering device.

[0003] Known vehicle steering devices comprise a steering wheel which has a gas bag module with a gas bag and a covering cap on the front side, the covering cap closing an outlet opening for the gas bag up to its unfolding.

[0004] In vehicles, the accommodating of instruments such as for example tachometers, revolution indicators and the like in the instrument panel and also of operating elements is very costly, and furthermore these instruments/operating elements are poorly accessible for repair. Furthermore, the instruments lie behind the steering wheel, so that they only lie in the optimum angle of view for persons of a particular size. In particular, short people can have a restricted view of the instruments owing to the steering wheel.

[0005] It is an object of the invention to simplify the equipping of the vehicle with the instrument display and/or operating elements. This is achieved in a vehicle steering device comprising a steering wheel which has a gas bag module with a gas bag and a covering cap on a front side. The covering cap closes an outlet opening for the gas bag up to its unfolding. At least one of a display- and operating device is arranged in the covering cap. The outlet opening runs around at least one of the display- and operating device. The vehicle steering wheel is equipped hitherto only with multifunction switches which adjoin the covering cap laterally. However, it does not serve to accommodate a display- and/or operating device. This has not been considered, because the gas bag module which takes up a large amount of space, tears open almost the entire covering cap and hence the entire hub region of the steering wheel in the case of restraint, so that thereby automatically there is no place available to accommodate the display- and/or operating device. The invention, on the other hand, makes provision that the outlet opening runs around the display- and/or operating device, so that the display- and/or operating device itself remains secured in a stationary manner on the steering wheel even when the covering cap tears open. For the signal transmission, devices are available which have already been developed in connection with the multifunction switches and also in connection with the triggering of the gas generator. The installation of the steering wheel itself is very simple and it can also be easily dismantled, which is a considerable advantage compared with the dismantling of display- and/or operating devices in the instrument panel. The covering cap can have a central depression or opening to house the display- and/or operating device.

[0006] Preferably, the outlet opening has a closed ring shape. The gas bag therefore emerges in symmetrical form and centrally, i.e. in the region of the hub, from the gas bag module in the direction towards the occupant.

[0007] Preferably the gas bag is also constructed in a ring shape and moves outwards via the outlet opening. The gas bag therefore, in the unfolded state, surrounds the display- and/or operating device which on unfolding of the gas bag remains fastened in a stationary manner on the steering wheel. The gas bag can join together radially inwards on its front wall, so that the indentation is not open from the exterior.

[0008] According an embodiment, the display device is a screen to display various vehicle data. The screen is therefore used universally and serves for example to indicate the speed, as a display of a navigation system, radio display, telephone display, WAP screen, PC display, as screen for the transmission/viewing of e-mails, as a touch screen for the combined display and operation of a device or as touch pad for the operating of vehicle elements.

[0009] A preferred embodiment makes provision that a steering angle detection sensor is provided which is coupled with the screen via a control arrangement. This control arrangement is engineered and programmed such that it controls the screen so as to be independent of the steering wheel's angular position, i.e. the screen always providing a horizontally aligned display, although the screen rotating together with the steering wheel since it is rigidly coupled with the latter.

[0010] FIGS. 1aand 1beach show a top view onto a steering device according to the invention,

[0011] FIG. 2 shows a side view of the steering device shown in FIG. 1 with unfolded gas bag,

[0012] FIG. 3 shows a second embodiment of the steering device according to the invention, and

[0013] FIGS. 4 to 6 show top views onto further embodiments of the steering device according to the invention.

[0014] FIGS. 1aand 1bshow a vehicle steering device with a steering wheel 10, in which a gas bag module 12 is housed in the region of the hub. The steering wheel 10 is illustrated in two differing angular positions. The gas bag module has a covering cap 14 on the front side, in the region of the hub, a gas generator 16 and a gas bag 18. The gas bag is fastened at its outer edge 20 on the base of the gas bag module 12. In relation to the unfolded state (see FIG. 2) the gas bag has a front wall 22 onto which the occupant strikes. The front wall 22 continues into an indentation 24 which is formed in that a central section of the gas bag wall remains fastened to the gas generator 16 via a fastening device 26 and hence is prevented from emerging from the gas bag module 12. Therefore, the gas bag has a ring-shaped form in the inflated state, with a ring-shaped chamber 28.

[0015] The covering cap 14 has numerous flaps 30 which are defined by given film hinges or predetermined breaking lines 32. These flaps 30 close a closed annular outlet opening 34 for the gas bag 18. The outlet opening 34 surrounds a display device, provided centrally in the covering cap 14, in the form of a LCD screen 36 which, depending on the desired setting, has at least one of the following functions: speed display, display of a navigation system, radio display, telephone display, WAP screen recall/transmission of e-mails, PC display and the like. Also, the remaining displays already provided hitherto in the vehicle can take place via the LCD screen. Preferably, all screens in the embodiments shown are LCD screens.

[0016] The screen 36 is likewise permanently fastened to the gas bag module 12 by means of the fastening device 26, so that on unfolding of the gas bag 18 and tearing open of the covering cap 14, it remains fastened to the steering wheel 10 in a stationary manner and rotates together with the rotating steering wheel. In addition, by means of multi-functional switches 40, various information can be called up and displayed on the screen 36. The screen 36 is coupled with a control arrangement 42 which in turn is connected with a sensor 44 to detect the steering wheel's angular position. In the control arrangement 42, in addition the remaining data are also entered, which are displayed on the screen 36. The control arrangement 42 controls the screen 36 such that independently of the steering angle, the screen always provides a horizontally formed display 46 (see FIG. 1b). If the steering wheel 10 is turned, then the display 46 is “turned” electronically about the same angle in the opposite direction, so that despite driving round a bend, the display 46 stands horizontally. The rotated screen 36 is indicated in broken lines.

[0017] In the embodiment according to FIG. 3, all the reference numbers already introduced in connection with FIG. 2 are used again for parts having the same function. In contrast to the embodiment according to FIG. 2, the gas bag 18′ according to FIG. 3 does not have an annular form. Rather, the gas bag has an outflow opening 50 which in the folded state lies underneath the screen 36. On unfolding, the edge of the outflow opening 50 slides upwards along the screen 36, so that finally the screen 36 lies inside the gas bag 18′. In this embodiment, too, the display 46 always remains in horizontal orientation due to the control arrangement 42, although the screen 36 rotates.

[0018] In the embodiment according to FIGS. 4aand 4b, to the left and right of the display device a pair of multifunctional switches 40 are arranged on the periphery of the covering cap 14. As in the embodiment according to FIG. 2, the display device is coupled with the control arrangement 42, which also applies to the multifunctional switch 40. The control arrangement 42 transmits signals to the display device which delivers a display 46 allocated separately to each multifunctional switch 40 and in fact such that the display indicates which functions are triggered by pressing the corresponding multifunctional switch 40. Thus, for example, the left-hand upper display 46 is associated with the left-hand upper multifunctional switch, by which a speedomat is controlled. A driver who does not know the functions of the multifunctional switch sufficiently is given information in a simple manner via the display—which can also take place by pictograms or the like—how the multifunctional switches are to be operated. The two right-hand multifunctional switches 40 in the state shown are in a setting in which the sound intensity of the radio or telephone can be altered. It is also possible that in a menu-controlled manner, by pressing the multifunctional switches, a jump can be made into other levels which always requires a complicated operation. Hitherto, it was necessary for the driver to know all the levels by heart so as not to have to try continuously by random. Through the invention, the numerous functions of an individual switch are made readily available to the driver. Here too, the display in the form of letters or symbols remains horizontally aligned, even when the screen rotates (see FIG. 4b). In the embodiment according to FIGS. 5aand 5b, a touch screen 36′ is arranged centrally in the covering cap 14, which screen 36′ represents a combined display- and operating device. Several fields 52 are provided with displays, which are able to be selected on contact, so that a menu is opened. For example, via the field “telephone” the entire screen can be used to display the telephone book, so that access can be made to individual entries very quickly. Functions such as sound intensity or selected frequency can be altered via the field “radio”. In FIGS. 5aand 5bthe display in the form of letters or symbols also remains horizontally aligned, even when the screen rotates.

[0019] In the embodiment according to FIGS. 6aand 6b, there is arranged in the center of the covering cap 14 a pure operating element 36″ in the form of a touch pad. By means of this operating field, the driver can for example, when the vehicle is stationary, quickly move a pointer to a screen arranged elsewhere and by pressing the touch pad he can select functions. For example, a display could be projected onto the windscreen which can be altered by means of the touch pad, by functions or menus being selected.

[0020] Also, a combination of operating elements and display devices is possible in the center of the covering cap 14.

[0021] According to the preferred embodiment, the outlet opening 34 is always constructed in a closed ring shape. However, an open ring shape is also possible, for example an outlet opening 34 in the form of a “U”.