A PLURALITY OF PARALLEL ROTATING SHAFTS

The present invention relates to a device for actuating a rotating shaft selected from a plurality of parallel rotating shafts.

Nowadays in the sector of isolating switches for high voltage which comprise an isolating switch and two earthing blades, for the rotation of the contact elements individual and independent drives are generally employed for each one of the elements to be rotated.

Such drives comprise a drive unit and a kinematic arrangement that is adapted to transmit the motion from the drive unit to the main part of the isolating switch or of the earthing blade.

Such conventional drives move, separately and independently, the contacts of the isolating switches, and the earthing blades that are installed upstream and downstream of the contacts of the isolating switches; mechanical means are also present for locking the various drives, as required by the national and international regulations governing isolating switches, which are adapted to prevent movements that are ungoverned, and thus unwanted, of the movable contact elements between an isolating switch and a corresponding earthing blade.

Such conventional drives, although appreciated for their functionality, have a number of drawbacks, the foremost of which is linked to the presence of a drive unit, kinetic mechanisms and locking means for each contact element to be moved, with corresponding proportional costs of manufacture and assembly.

Furthermore each one of the drive units has to be electrically powered separately from the others, with consequent dedicated civil engineering works.

What is more, each drive unit with corresponding kinetic mechanisms and locking means has to be contained in a corresponding protection enclosure. The aim of the present invention is to provide a device for actuating a rotating shaft selected from a plurality of parallel rotating shafts, which is capable of overcoming the above mentioned drawbacks of conventional drives.

Within this aim, an object of the invention is to provide a device that comprises a lower number of components with respect to similar, conventional driving devices, and which at the same time is capable of fully executing the same activities.

Another object of the invention is to provide a device that renders the assembly of an isolating switch simpler, and the related civil engineering works less expensive.

Another object of the invention is to provide a device that can be governed both automatically and manually.

Another object of the invention is to provide a device that is capable of reducing the general costs for the drive unit of an isolating switch and the costs of running such drive unit.

This aim and these and other objects which will become better apparent hereinafter are all achieved by a device for actuating a rotating shaft selected from a plurality of parallel rotating shafts, characterized in that it comprises:

- a driving shaft supported and actuated by corresponding rotation means, which is provided with a driving gear for the transmission of torque,

- a plurality of driven shafts, each one of which is provided with a corresponding driven gear that is designed to be meshed with said driving gear,

said driven gears being arranged on the respective driven shaft in an axial position that is offset with respect to the other driven gears,

said driving gear being capable of performing a translational movement axially with means of translational motion for alternate meshing with one of said driven gears, said device further comprising means of prevention of rotation for the driven shafts whose driven gear is not meshed with said driving gear.

Further characteristics and advantages of the invention will become better apparent from the description of a preferred, but not exclusive, embodiment of the device according to the invention, which is illustrated by way of non-limiting example in the accompanying drawings wherein:

Figure 1 is a view of the device according to the invention;

Figure 2 is a perspective view of a detail of the device in Figure 1.

With reference to the figures, a device for actuating a rotating shaft selected from a plurality of parallel rotating shafts according to the invention is generally designated with the reference numeral 10.

Such device 10 comprises:

- a driving shaft 11 supported and actuated by corresponding rotation means 12, which is provided with a driving gear 13 for the transmission of torque,

- three driven shafts, 14, 15 and 16 respectively, each one of which is provided with a corresponding driven gear 17, 18 and 19 that is designed to be meshed with the driving gear 13.

The driven gears 17, 18 and 19 are arranged on the respective driven shaft 14, 15 and 16 in an axial position that is offset with respect to the other driven gears.

The driving gear 13 is capable of performing a translational movement axially with means of translational motion 20 for alternate meshing with one of the driven gears 17, 18, 19.

The device 10 also comprises means 21, better described hereinbelow, of prevention of rotation for the driven shafts whose driven gear is not meshed with the driving gear 13.

The driving shaft, with its rotation means, and the three driven shafts are supported by a structure which should be understood as being of known type and is not shown for the sake of simplicity. The rotation means 12 for the driving shaft comprise an electric motor with a reduction gearbox 22.

Such rotation means 12 also comprise a crank 23 for the manual actuation of the device 10 if necessary.

The means of translational motion 20 for the alternate meshing of the driving gear 13 with one of the driven gears 17, 18, 19 are constituted, by way of non-limiting example of the invention, by an electromechanical actuator of conventional type.

Such means of translational motion 20 can be actuated by way of an electric motor 24, or alternatively, in the event of no electric power supply, manually by way of a crank 25.

In the present embodiment of the device 10 according to the invention, described herein by way of non-limiting example of the invention, in the means 21 of prevention of rotation for the driven shafts that are not actuated, the driven shafts 14, 15 and 16 are arranged with the same distance between centers with respect to the axis of the driving shaft 11.

Such means of prevention of rotation 21 are constituted, for each rotating shaft 11, 14, 15, 16, by a disk-like body, 26, 27, 28, 29 respectively, the three disk-like bodies corresponding to the three driven shafts being fixed coaxially to the corresponding shaft, while the central disk-like body 26 is supported by the driving shaft 11 but is decoupled from it in terms of rotation.

Each disk- like body has a concave sector, 40, 41, 42, 43 respectively, with a profile shaped like a circular arc; the concavity of the concave sectors 41, 42, 43 of the driven disk-like bodies 27, 28, 29 has a slightly greater radius than the radius R of the central disk-like body 26, while the concavity of the concave sector 40 of the central disk-like body 26 has a contour and dimensions that are such as to allow, thereat, the rotation of each of the driven disk-like bodies 27, 28, 29. In this manner the driven disk-like bodies 27, 28 and 29 can all be locked alternately by the central disk-like body 26 and each one of them is free to rotate when the concave sector 40 of the central disk-like body 26 is facing toward it.

In particular, in the present embodiment, the disk-like bodies 26, 27,

28, 29 have the same radius R which is greater than half of the distance between centers 30.

Each disk- like body has a concave sector, 40, 41, 42 and 43 respectively, with a profile shaped like a circular arc.

The concavity of such concave sector has a slightly greater radius than the radius R of the disk-like bodies.

The disk-like bodies are keyed, on the respective rotating shafts, mutually coplanar.

Such means of prevention of rotation 21 function as described below. The central disk-like body 26, which is coaxial with the driving shaft

11, can assume an angular position selected from a number of positions which is equivalent to the number of driven shafts, three in the present embodiment.

The central disk-like body 26, as in Figure 2, can be rotated and positioned so that its concave sector 40 is facing toward the third disk-like body 29, and in such situation the third disk-like body 29 is free to rotate together with the third driven shaft 16; at the same time the central disk-like body 26 occupies, with corresponding perimetric portions, the concave sectors 41 and 42 respectively of the first disk-like body 27 and of the second disk-like body 28, thus preventing the rotation of these latter two.

The central disk-like body 26 is able to rotate so as to be arranged with its concave sector 40 facing toward any one of the three disk- like bodies 27, 28 and 29 of the driven shafts 14, 15 and 16, thus alternately freeing the rotation of one driven shaft only with the simultaneous locking of the other two. The rotation of the central disk-like body 26 is provided by way of the same electric motor 24 that commands the electromechanical actuator for the driving gear, by way of means of transmission of rotation which are adapted to synchronize the translational motion of the driving gear 13 toward the engagement with one of the driven gears 17, 18 and 19, with the simultaneous rotation of the central disk-like body 26 so as to free the rotation of the disk-like body 27, 28 or 29 corresponding to the driven gear with which the driving gear 13 is to mesh.

This can be made possible for example by way of two concentric shafts, which are locked in mutual rotation, i.e. designed to rotate together, but of which one is capable of performing a translational movement with respect to the other; the outer shaft can perform a translational motion with respect to the inner shaft supporting the driving gear 13, while the inner shaft, which is axially fixed, supports the central disk-like body 26 thus making it rotate.

The means of translational motion 20 with the electric motor 24, and the corresponding means 21 of prevention of rotation can be supported by the driving shaft 11.

In practice it has been found that the invention fully achieves the intended aim and objects.

In fact, with the invention a device for actuating a rotating shaft selected from a plurality of parallel rotating shafts is provided which makes it possible to employ a single motor to alternately actuate one of a plurality thereof, thanks to the coordinated actuation of the means of translational motion 20 for the alternate meshing of the driving gear 13 with one of the driven gears 17, 18, 19, and of the means 21 of prevention of rotation for the driven shafts that are not actuated, which determine the simultaneous locking of two driven shafts and the transmission of power to the third driven shaft, which remains free to rotate.

Furthermore, with the invention a device is provided that makes it possible to move a rotating shaft selected from a plurality of rotating shafts, with the shafts that are not made to rotate being kept stably motionless in a precise preset configuration of non-use thanks to the aforesaid means of prevention of rotation, as required by the national and international regulations governing isolating switches.

What is more, with the invention a device is provided which is constituted by a lower number of components with respect to similar, conventional driving devices, and at the same time is capable of fully executing the same activities, thus at a lower cost from the viewpoint of its production and from the viewpoint of assembly, and also from the viewpoint of maintenance.

Furthermore, with the invention a device is provided which renders the related civil engineering works less expensive, since the electrical drive units are coaxial and very proximate to each other and can be reached with a single electrical line, and not with three separate electrical lines as with the drives for three shafts with a corresponding number of corresponding drive units, typical of conventional isolating switches.

Furthermore, with the invention a device is provided which can be protected by way of a single containment and protection enclosure, instead of with three separate containment enclosures as with the drives for three shafts with a corresponding number of corresponding drive units of the known type.

With the invention a device is thus devised which is capable of reducing the general costs for the drive unit of an isolating switch and the costs of running such drive unit.

The invention, thus conceived, is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements.

In practice the components and the materials employed, provided they are compatible with the specific use, and the contingent dimensions and shapes, may be any according to requirements and to the state of the art.

Where technical features mentioned in any claim are followed by reference signs, such reference signs have been inserted for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.