The present invention relates in general to a control device comprising a support structure and a control lever manually operable by the user, wherein the control lever is supported by the support structure so that it is able both to tilt to the left and to the right about a first axis of rotation oriented longitudinally, and to tilt forwardly and backwardly about a second axis of rotation directed transversally.

More specifically, the present invention relates to a control device of the type indicated above, wherein the control lever is normally kept in a given angular position (stable position) about the first axis of rotation, so as to tilt forwardly and backwardly about the second axis of rotation in a given selection plane (primary selection plane). The control lever of the present invention, thus, has only a single stable position about the first axis of rotation. The control lever can be rotated about the first axis of rotation to be brought into at least one further selection plane (secondary selection plane), inclined by a given angle with respect to the primary selection plane, and be tilted forwardly and backwardly in said secondary selection plane by rotation about the second axis of rotation.

A control lever according to the invention is advantageously, though not necessarily, in- tended to be used to control a gearbox of a motor vehicle, particularly an automatic gearbox. In this case, the primary selection plane is the plane in which the various operative modes of the gearbox are selectable, typically the normal driving mode, the idle mode, the reverse mode and the parking mode, normally indicated with D, N, R and P, respectively. The secondary selection plane, on the other hand, is the plane in which the control lever is tilted forwardly and backwardly, starting from a stable central position, in order to engage the immediately next higher gear or the immediately next lower gear with respect to the one currently engaged, according to a so-called sequential operating mode.

As the control lever is stably kept in the/primary selection plane, a control device of the type specified above is typically provided with controllable locking means arranged to keep the control lever in the secondary selection plane, once the control lever has been displaced by the operator in said plane by rotation about the first axis of rotation, and to al- low, when needed, the return of the control lever back in the primary selection plane. In case the control device is used for example to control an automatic gearbox of a motor vehicle, said locking means act when the control lever is displaced by the driver in the secondary selection plane to engage the gears sequentially, in order to keep the control lever in said plane and to force thus the lever to tilt in said plane about the second axis of rotation. Additionally, when the engine of the vehicle is switched off with the gearbox working in sequential mode, said locking means are controlled to bring the control lever back in the primary selection plane. According to the prior art, said locking means are typically formed by electro-mechanical actuation devices comprising an electric motor and an actuation mechanism that act on the gearbox control lever through cams or like control members to lock the control lever in the secondary selection plane or bring it back from the secondary selection plane to the primary selection plane. Locking means of this type are, nonetheless, complex, bulky and expen- sive.

It is thus an object of the present invention to provide a control device of the above identified type, wherein the locking means are simpler, less bulky and less expensive than the prior art.

This and other objects are fully achieved according to the present invention by virtue of a control device as defined in the enclosed independent claim 1.

Preferred embodiments of the invention form the subject-matter of the dependent claims, the content of which is to be intended as forming an integral and integrating part of the present description.

In short, the invention is based on the idea of providing a control device of the above- identified type, comprising biasing means exerting a biasing action on the control lever tending to bring the control lever back in the primary selection plane when the control lever is brought in the secondary selection plane (or in each of the secondary selection planes, in case more than one selection plane are provided for) by rotation about the first axis of rotation, and controllable locking means arranged to keep the control lever in the secondary selection plane, overcoming the biasing action exerted by the biasing means, when the control lever is positioned in the secondary selection plane, wherein said locking means comprise, for each secondary selection plane, a respective electromagnet fixed to the sup- port structure and, for each electromagnet, a respective insert of ferromagnetic material that is mounted so as to be drivingly connected with the control lever for rotation about the first axis of rotation and is arranged to be kept in contact with the respective electromagnet when the control lever is in the respective secondary selection plane and the respective electromagnet is energized.

The use of such electromagnets as locking means for locking the control lever in the secondary selection plane (or in each secondary selection plane, in case more than one secondary selection plane are provided for) makes the control device clearly simpler, less bulky and less expensive. Additionally, the automatic return of the control lever back in the primary selection plane is ensured in the event of electric power interruption, for example, if the control device is used to control the gearbox of a motor vehicle, when the engine of the vehicle is switched off with the control lever positioned in a secondary selection plane, as the biasing means exert on the control lever an action tending to bring the control lever from the secondary selection plane back to the primary selection plane.

Further features and advantages of the present invention will become apparent from the following detailed description, given purely by way of non-limiting example with reference to the appended drawings, where:

Figure 1 shows a control device according to an embodiment of the present inven- tion, with the control lever positioned in the primary selection plane;

Figure 2 shows the control device of Figure 1 , with the control lever positioned in the secondary selection plane; and

Figure 3 schematically shows the various positions in which the control lever of the control device of Figures 1 and 2 can be positioned.

The invention will be hereinafter described with particular reference to the application of the control device to the control of an automatic gearbox of a motor vehicle. Such an ap- plication is however to be intended as being purely examplary and, thus, not limiting the scope of the invention, the control device of the invention being usable in any application requiring that the control lever is able to tilt in a primary selection plane and in one or more secondary selection planes rotated with respect to the primary selection plane.

In the following description and claims terms like "longitudinal" and "transverse", as well as "horizontal" and "vertical", are to be intended as referred to the mounted condition of the control device on board of the vehicle, the term "longitudinal" indicating a direction parallel to the front-rear direction (or driving direction) of the vehicle and the term "trans- versal" indicating a direction perpendicular to the longitudinal direction.

With reference to Figures 1 and 2, a control device according to an embodiment of the present invention is generally indicated with 10. The control device 10 comprises, first of all, a control lever 12 through which the user (driver) is able to give commands to a de- vice/system to be controlled (here, an automatic gearbox of a motor vehicle). The control lever 12 comprises in turn, in a per-se-known manner, a rod 14 and a knob (not shown, but of per-se-known type, though) mounted on the top end of the rod 14.

The control device 10 further comprises a support structure 16 on which the control lever 12 is supported so as to be able to tilt about two perpendicular axes of rotation, namely a first axis of rotation x directed longitudinally and a second axis of rotation y directed transversally. By rotation about the first axis of rotation x the control lever 12 tilts in a transverse plane to the left or to the right, whereas by rotation about the second axis of rotation y the control lever 12 tilts forwardly and backwardly oin a longitudinal plane.

Preferably, the first axis of rotation x is a stationary axis, i.e. an axis that is fixed with respect to the support structure 16, whereas the second axis of rotation y rotates about the first axis of rotation x together with the control lever 12 when the latter is tilted in either direction about the first axis of rotation x.

According to the embodiment shown in the drawings, the control lever 12 is rotatably mounted on a tilting body 18 about the second axis of rotation y and the tilting body 18 is in turn rotatably mounted on the support structure 16 about the first axis of rotation x. The control lever 12 is thus drivingly connected with the tilting member 18 for rotation about the first axis of rotation x, while it is rotatable relative to the tilting body 18 about the second axis of rotation y.

The control lever 12 is normally kept in a given angular position about the first axis of rotation x to tilt forwardly and backwardly about the second axis of rotation y in a given selection plane, hereinafter referred to as primary selection plane, with respect to the support structure 16. In the embodiment shown in the drawings (see Figure 1), the primary selec- tion plane is oriented vertically, and therefore the second axis of rotation y is directed horizontally. Alternatively, the selection plane might also be inclined by a given angle with respect to the vertical, and therefore the second axis of rotation y be correspondently inclined with respect to the horizontal. When the control lever 12 is in the primary selection plane, the user can move the control lever 12 forwardly and backwardly, making it tilt about the second axis of rotation y, in a plurality of positions each corresponding to a given command to be given to the device/system controlled by the control device 10. Starting from said normal position, wherein the control lever 12 is movable forwardly and backwardly in the primary selection plane, the control lever 12 can be tilted to the left or to the right about the first axis of rotation x to be brought in at least one secondary selection plane, as shown in Figure 2. In the embodiment proposed herein, one single secondary selection plane is provided for, which is inclined to the right (with respect to the point of view of the observer of the figures) by a given angle a with respect to the primary selection plane. When the control lever 12 is in the secondary selection plane, the user can move the control lever 12 forwardly or backwardly, making it tilt about the second axis of rotation y (which will be inclined by the same angle a with respect to the direction along which the second axis of rotation y lies when the control lever 12 is in the primary selection plane), in a plurality of positions each corresponding to a given command to be given to the device/system controlled by the con- trol device 10.

With reference to Figure 3, in the embodiment proposed herein the primary selection plane (indicated πΐ) is the plane in which the gearbox works in automatic mode. With the control lever 12 placed in the primary selection plane, the driver can thus select the various operating modes of the gearbox, in particular the normal driving mode, the idle mode, the reverse mode and the parking mode, respectively indicated with D, N, R and P. Of course, further modes can be provided for in addition to those shown in Figure 3. The secondary selection plan (indicated π2) is the plane in which the gearbox is controlled in sequential mode. With the control lever 12 placed in the secondary selection plane, the driver can select the immediately next higher gear or the immediately next lower gear with respect to the one currently selected by tilting the control lever 12 forwardly (position indicated "+") and back- wardly (position indicated "-"), respectively, starting from a stable central position.

Of course, in order to detect the angular position of the control lever 12 about the second axis of rotation y, either when the control lever 12 is in the primary selection plane and when the control lever 12 is in the secondary selection plane, the control device 10 is pro- vided with position sensing means, for example, Hall effect sensors. Such position sensing means are of per-se-known type and thus are not described in detail here.

In order to normally keep the control lever 12 in the primary selection plane, the control device 10 further comprises biasing means exerting a biasing action on the control lever 12 tending to bring the control lever 12 back to the primary selection plane when the control lever 12 is moved to the secondary selection plane by rotation about the first axis of rotation x.

In the embodiment shown in the drawings, such biasing means comprise a cam 20 formed by the tilting body 18 and a wheel 22 kept in contact with the cam 20. The wheel 22 is mounted idle at one end of a slider 24 that is slidably mounted in a special guide cavity provided in the support structure 16. The slider 24 is pushed by a spring (not shown) toward the cam 20. More precisely, the cam 20 is substantially V-shaped, with a pair of surfaces 20a inclined by a given angle to the horizontal and converging one toward the other at a vertex 20b that is vertically aligned with the first axis of rotation x. The guide cavity extends vertically, so that the slider 24 slides vertically along the guide cavity and is pushed downwardly by the spring toward the cam 20. The interaction between the spring- loaded slider 24 and the associated wheel 22 with cam 20 causes the tilting body 18 to be stably kept in an angular position about the first axis of rotation x such that the wheel 22 is positioned at the vertex 20b of the cam 20. Such a position defines the primary selection plane of the control lever 12. A movement of the control lever 12 to the left or to the right from this position causes, by virtue of the interaction between the wheel 22 and the cam 20, a compression of the spring acting on the slider 24, with the consequence that when the driver releases the control lever 12, the latter moves back into its initial position (i.e. in the primary selection plane) under the action of the elastic force exerted by the spring on the slider 24 and, through the wheel 22, on the cam 20 of the tilting body 18.

Even if only one cam 20 and one wheel 22 are shown in Figures 1 and 2, the control device 10 preferably comprises one further cam and one further wheel placed on the opposed side of the first cam and the first wheel with respect to a vertical plane passing through the second axis of rotation y.

Of course, the inclination of the surfaces 20a of the cam 20 and/or the stiffness of the spring acting on the assembly formed by the slider 24 and the wheel 22 will be suitably chosen to produce the desired biasing force on the control lever 12. Furthermore, the arrangement of the cam and of the wheel might be inverted with respect to the one shown herein, in that the cam might be fixed to the support structure and the wheel be supported by the tilting body.

The control device 10 further comprises controllable locking means for locking the tilting body 18, and thus the control lever 12, in a given angular position about the first axis of ro- tation x corresponding to the positioning of the control lever 12 in the secondary selection plane.

According to the invention, such locking means are formed by an electromagnet 26. In the proposed embodiment, the electromagnet 26 is fixed to the support structure 16 and coop- erates with an insert 28 of ferromagnetic material that is fixed to the tilting body 18 (that is preferably made of plastics material). The electromagnet 26 and the insert 28 are positioned in such a way that when the control lever 12 is in the secondary selection plane, the insert 28 carried by the tilting body 18 is in contact with the electromagnet 26. In this way, if the electromagnet 26 is energized, it produces a magnetic attractive force on the insert 28 which keeps the latter in contact with the electromagnet 26, and thus keeps the control lever 12 in the secondary selection plane. The user can thus operate the control lever 12 by moving it forwardly or backwardly in the secondary selection plane. As soon as the electromagnet 26 is de-energized, for example when the engine of the vehicle is switched off, the control lever 12 returns automatically back in the primary selection plane by virtue of the biasing action exerted by the biasing means described above. It is thus avoided the need to provide a special actuation device for bringing the control lever back in the primary se- lection plane when the engine of the vehicle is switched off.

Even if in the embodiment shown in the drawings the control device only has one secondary selection plane, a further secondary selection plane may be provided for on the opposite side of the first secondary selection plane with respect to the primary selection plane, in which case the locking means would comprise a further electromagnet to cooperate with a further insert of ferromagnetic material fixed to the tilting body so as to allow the control lever to be locked also when the control lever is positioned in this further secondary selection plane. Naturally, the principle of the invention remaining unchanged, the embodiments and the constructional details may vary widely from those described and illustrated purely by way of non-limiting example, without thereby departing from the scope of the invention as defined in the enclosed claims.