Technical Field

The present invention relates to a device for moving an object, particularly a rigid object, over ground, on flat, soft or rough terrains. More particularly, the invention relates to a device for moving an object with respect to the ground without resorting to wheels, which especially for example on soft terrains do not give assurances of effectiveness.

Background Art As it is known, all overland movement systems, including cable systems and tracked vehicles, are based on the wheel-way kinematic pair, either with a conventional or rail-equipped ground way, or with an overhead way, such as cable systems, or with a way which moves with the vehicle, as in the case of tracked vehicles. For travel on soft terrains, the solution most widely used, in addition to tracks, is currently a low-pressure wheel with large surfaces of contact

(and high energy costs for travel).

There are cases with a very large number of wheels and great capacities for relative displacement among the wheels in order to ensure contact on rough terrains, but the principle is always the wheel-way pair, with all the limitations that arise from this in terms of grip and adaptability to the supporting ground.

If it is necessary to move extremely bulky objects, for which the presence of wheels can sometimes be difficult to implement, and especially for which wheels are unable to act adequately, for example on soft or rough terrains, movement becomes a problem which substantially cannot be solved unless resorting to appropriate lifting means.

Of course, such means are not easily available when it is necessary to move the object. Moreover, it often happens that it is necessary to move an object

periodically. For example, in the case of small outdoor swimming pools, it is often necessary to transfer the pool outside a building in summer and return it indoors during the winter season. These transfers are of course extremely difficult in the absence of an adapted movement device. Disclosure of the Invention

The aim of the present invention is to provide a device for moving objects, particularly of the rigid type, over ground, which allows to move the object very simply both on level terrains and on rough terrains.

Within this aim, an object of the present invention is to provide a device for moving an object over ground which can be placed in an active condition when necessary and can otherwise be kept in the inactive condition.

Another object of the present invention is to provide a device for moving an object which allows the advancement of the object both in a straight line and along a curved line without using conventional tracks or wheels.

Another object of the present invention is to provide a device for moving an object which is highly reliable, relatively simple to provide and at competitive costs. This aim and these and other objects, which will become better apparent hereinafter, are achieved by a device for moving an object over ground, characterized in that it comprises means which are adapted to perform a vertical translational motion and a horizontal translational motion, said means being connected to the object so as to make the object perform a stepwise advancement.

Brief description of the Drawings

Further characteristics and advantages of the invention will become better apparent from the following detailed description of preferred but not exclusive embodiments of the movement device according to the present invention, illustrated by way of non-limiting example in the accompanying

drawings, wherein:

Figures Ia to Ie illustrate the movement of an object by means of the device according to the invention, according to a first embodiment thereof;

Figures 2a to 2f illustrate the movement of an object with the device according to a second embodiment of the present invention;

Figures 3a to 3 f illustrate the movement of an object by means of the device according to a third embodiment of the present invention. Ways of carrying out the Invention

With reference to the figures, using the reference numeral 1 to designate an object which must be moved schematically over ground and is for example shaped like a parallelepiped, the device according to the invention, and to a first embodiment thereof, comprises, as shown in Figures

Ia-Ie, one or more motion means, designated by the reference numeral 2, adapted to produce a translational motion at right angles to the ground on which the object 1 rests (lifting) and a subsequent translational motion which is parallel to said ground (movement).

The motion means 2 are constituted conveniently for example by one, and preferably two, pairs of extensible elements, which can extend in order to move the object 1 from a position in which it rests on feet 3 and 4 of the object to a position, shown in Figure Ib, in which the object 1 is suspended by way of the extensible means 2.

Moreover, the extensible means 2 are adapted to perform a translational motion which is parallel to the ground, so as to be able to perform a "step", thus producing the advancement of the object 1 to which they are connected.

Figure Ib illustrates the step of extension of the extensible means 2 and therefore of unloading the feet 3 and 4 of the object 1.

Figure Ic illustrates the step of translational motion of the object 1 with respect to the extensible means 2, with advancement by one step. The step that the object 1 can make is equal to the distance between the

extensible means 2 and the feet 3 and 4, alternately.

Figure Id instead illustrates the step of shortening the extensible means 2, with subsequent transfer of the load to the feet 3 and 4 and consequent repositioning of the object 1 on the ground. Figure Ie illustrates a step which is similar to the step shown in

Figure Ib and in which the extensible means 2 extend again in order to lift from the ground the object 1 and therefore perform a second step.

In this manner, the advancement of the object 1 occurs by means of an initial step of vertical translational motion and a subsequent step of horizontal translational motion, where "horizontal" and "vertical" are always indicated with reference to the supporting ground ("average" contour in the points of contact).

Figures 2a to 2f illustrate a second embodiment of the device according to the invention, in which the means adapted to produce a vertical translational motion and a horizontal translational motion are constituted for example by rod-like elements 10, which are pivoted at a lateral region of the object 1. Preferably, therefore, there are two pairs of rod-like elements 10, one for each side of the object 1.

In this case, the vertical translational motion and the horizontal translational motion are combined in an oscillation of the rod-like elements 10 about their pivoting point.

In this manner, as shown in Figure 2a, the object 1 initially is in the resting position, with the rod-like elements 10 extended and with the stroke at the beginning of the step. The transfer of the load from the feet 3 and 4 to the rod-like elements 10 occurs gradually during the rotation of said rod-like elements.

Figure 2b illustrates the translational motion of the object 1 obtained by oscillation of the rod-like elements with advancement by half a step. The object 1 rises by rotation of the rod-like elements 10. Figure 2c illustrates the translational motion of the object 1 by the

second half step, obtained by completion of the oscillation of the rod-like elements 10 up to the stroke limit which lies opposite the step start stroke limit, shown in Figure 2a.

Figure 2d illustrates the lifting of the rod-like elements 10 obtained by rotating eccentric means which support the oscillation pivots of the rod- like elements 10, with simultaneous transfer of the load from the rod-like elements 10 again to the feet 3 and 4 of the object 1.

Figure 2e illustrates a retransfer of the rod-like elements 10 into the step start position, performed with the rod-like elements 10 in the raised position and with the load on the feet 3 or 4.

Finally, Figure 2f illustrates a position which is similar to the one shown in Figure 2a and in which the rod-like elements 10 are ready to perform a second step and therefore move again the object 1 to which they are connected. Finally, Figures 3 a-3f illustrate a third embodiment of the movement device according to the present invention, in which the means for vertical and horizontal translational motion are constituted by a deformable (concertina) air cushion, designated by the reference numeral 20.

Conveniently, two air cushions, one for each side of the object 1 to be moved, are provided.

In Figure 3a, the load is on the feet 3 and 4 of the object 1, with the air cushion or concertina element 20 in the extended position with the stroke at the beginning of the step. Transfer of the load from the feet 3 and 4 to the air cushion element 20 occurs by increasing the pressure of the (concertina) air cushion and consequently extending said air cushion.

Figure 3b illustrates the translational motion of the object 1 obtained by shearing deformation of the concertina 20 with advancement by half a step. The object 1 rises due to the axial expansion of the concertina 20.

Figure 3c illustrates the translational motion of the object by the second half step, obtained by completing the deformation of the concertina

element 20 until the stroke limit opposite to the step start stroke limit is reached.

Figure 3d illustrates the lifting of the air cushion element 20 obtained by reducing the pressure and by way of an elastic return toward the contracted position. At the same time, the object 1 moves downward and the load is transferred again from the air cushion element or concertina 20 to the feet 3 and 4.

Figure 3e illustrates the retransfer of the concertina element to the step start position, performed with the air cushion element 20 in the contracted position and with the load on the feet 3 and 4.

Finally, Figure 3 f illustrates a condition such as the one of Figure 3 a, with the object 1 ready for a subsequent step.

The movement means described above allow to trace both curved paths, simply by keeping a difference in the length of the step of one side of the object with respect to the step of the other side, or by varying the frequency of the step of one side with respect to the frequency of the step of the other side. A higher speed per step (breadth and/or frequency of the steps) on the right side produces, for example, turns to the left, and likewise a higher speed on the left side produces turns to the right. It is also possible to perform turns on the spot, i.e., turns without any translational motion of the object 1, by performing the step of one side with the same breadth and frequency, but with the opposite sign, with respect to the step of the other side of the object.

If the ground is rather even, movement control can be limited to the management of the cycle described above. It is necessary to perform the typical step, stop it in any position, and adjust the breadth and sign in the step in order to make turns.

In the case of uneven ground, with considerable longitudinal or transverse inclinations, movement control must instead provide for commands required to ensure that the trim of the object is maintained, i.e.,

substantially, in addition to the function provided for "even terrains", it must allow the independent adjustment of the lengths of the feet and of the means for vertical and horizontal translational motion. Various degrees of automation are possible for doing this and allow, in addition to the direct intervention of the operator if required (or in the case of no automation), to maintain the trim of the object stable with a suitable angular tolerance.

The two angles about the horizontal longitudinal axis and the transverse horizontal axis are monitored by means of gravity-based or gyroscopic systems or any other method adapted to contain costs and ensure adequate response times.

The objects or bodies to be moved with the type of movement described above are heavy furniture or machines which must be repositioned, as well as vehicles in situations of insufficient grip.

For all objects to be moved which are already provided with wheels, the feet described in the preceding embodiments generally correspond to the wheels with which the object is already provided.

The third embodiment of the invention, which provides for the use of "cushions", for example four small ones arranged near the pairs of feet 3 and 4, or two central larger ones, is considered interesting because it can be adapted easily to any type of ground, both indoors and outdoors, for example even to stairs, and with low pressures of the internal fluid, such as low-pressure air.

In practice it has been found that the movement device according to the invention fully achieves the intended aim and objects, since it allows to move over ground an object, with a stepwise advancement, by way of the means for vertical and horizontal translational motion with respect to the ground.

The device thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Thus, for example, in the case of very uneven or rough terrains or for

objects whose trim must be ensured constantly with higher precision, so as to require the adjustment of one or more of the feet 3 and 4, the higher cost of the foot adjustment and control systems can be reduced by introducing the possibility for the feet 3 and 4 to perform the function of the vertical and horizontal translational motion means, thus having feet which behave like the extensible means of the first embodiment, or like the rod-like elements of the second embodiment, or finally like the air cushion elements of the third embodiment.

In this case, it becomes evident that it is necessary to ensure an "almost static" balance of the object on the base formed on the ground by three of the four feet, while the fourth foot is moved into a new configuration in order to perform advancement.

For this purpose, it is possible to either arrange in the object a moving mass, which can return its center of gravity within the supporting triangle constituted by the three feet that rest on the ground, or maintain an arrangement of the three feet that form the supporting triangle with a perimeter which is sufficiently spaced from the projection of the center of gravity on the ground, so as to achieve a wide safety margin, or also to stabilize the balance with a mixed system of both of the preceding solutions. Moreover, the operating principle can be also reduced to a single means for step-by-step movement (or two), and the feet 3 and 4 in this case can slide on the ground during movement. This essential version, with a single step generation means, controls the direction of advancement by orienting the step with respect to the object. In the version with two step generation means, it is instead possible to vary the direction of the object 1 as mentioned in the case of the four means described above. In the case of a single step generation means, the rotation of the object 1 occurs manually or by controlling the mutual rotation between the object and the step generation means with a suitable mechanism, when the object is lifted and therefore sliding on the ground is minimal.

All the details may further be replaced with other technically equivalent elements.

In practice, the materials used, as well as the contingent shapes and dimensions, may be any according to requirements and to the state of the art.

The disclosures in Italian Patent Application No. MI2005A000459 from which this application claims priority are incorporated herein by reference.