TRANSMISSION OF ENDLESS ROTATION TO A SHAFT ON AN ENDLESSLY ROTATING CARRIER INDEPENDENTLY OF THE ROTATION OF THE CARRIER

Abstract

For the transmission of endless rotation from stationary frame to endlessly rotating carrier, or vice versa, independently of the rotation of the carrier, an efficient mechanical mechanism is missing.

A Compound Planetary Mechanism, named “Eleuthero-Strophe”, is proposed, with the already existing central carrier, two suns, an eccentric planetary carrier on which an eccentric satellite shaft rests bearing satellites, and planets which cooperate with the suns and the satellites, where all gear teeth numbers meet an Independence Condition. Main applications: horizontal axis wind turbine, where endless rotation of propeller shaft is transmitted to stationary tower, excavator or battle tank, where endless rotation is transmitted from chassis to turret, holonomic vehicle, where endless rotation is transmitted from chassis to drive wheel, propeller-driven aircraft, helicopter, propeller-driven craft, or wind turbine, where propeller pitch adjustment is achieved,
independently of endless rotation of the nacelle, the turret, the steering bracket, and the propeller hub, respectively.

Claims

1.-10. (canceled)

11. A compound planetary mechanism which has: a frame (00), a first carrier (10), named “central carrier”, the axis of rotation of which is named “central axis”, while the central carrier (10) is supported on the frame (00) and able to rotate freely and endlessly about the central axis, a first gear, named “reaction sun”, which is either preferably rigidly connected to the frame (00) coaxially with the central axis or supported on the frame (00) and able to rotate freely and endlessly about the central axis, is preferably a spur gear and either external (S1) or internal (I1), with a teeth number Z.sub.S1 or Z.sub.I1, respectively, a second gear, named “action sun”, which is supported on the frame (00) and able to rotate freely and endlessly about the central axis, is preferably a spur gear and either external (S8) or internal (I8), with a teeth number Z.sub.S8 or Z.sub.I8, respectively, and is either the input or the output of the compound planetary mechanism, and is characterized by the following: it has, at least, one simple planetary mechanism which consists of: a second carrier (20), named “planetary carrier”, which is supported on the central carrier (10) and able to rotate freely and endlessly about an axis, named “planetary axis”, preferably parallel to the central axis and at a distance from the central axis, while the planetary carrier (20) has, at least, one first shaft (45), named “satellite shaft”, which is supported on the planetary carrier (20) and able to rotate freely and endlessly about an axis, named “satellite axis”, which has a specific and permanent direction between parallel and perpendicular to the planetary axis, preferably either exactly parallel to the planetary axis and at a distance from the planetary axis or exactly perpendicular to the planetary axis, while there is a third gear, named “reaction satellite”, rigidly connected to the one end of the satellite shaft (45) coaxially with the satellite axis, which is either spur (S4) or bevel (B4), with a teeth number Z.sub.S4 or Z.sub.B4, respectively, as well as a fourth gear, named “action satellite”, rigidly connected to the other end of the satellite shaft (45) coaxially with the satellite axis, which is either spur (S5) or bevel (B5), with a teeth number Z.sub.S5 or Z.sub.B5, respectively, a second shaft (23), named “planetary reaction shaft”, which is supported on the planetary carrier (20) and able to rotate freely and endlessly about the planetary axis, while there is a fifth gear (S2), named “reaction sun-planet”, rigidly connected to the one end of the planetary reaction shaft (23) coaxially with the planetary axis, being such a gear as to properly cooperate with the reaction sun (S1 or I1), with a teeth number Z.sub.S2, as well as a sixth gear, named “reaction satellite-planet”, rigidly connected to the other end of the planetary reaction shaft (23) coaxially with the planetary axis, being either spur (S3) or bevel (B3) and cooperating with the reaction satellite (S4 or B4, respectively), with a teeth number Z.sub.S3 or Z.sub.B3, respectively, a third shaft (67), named “planetary action shaft”, which is supported on the planetary carrier (20) and able to rotate freely and endlessly about the planetary axis, while there is a seventh gear, named “action satellite-planet”, rigidly connected to the one end of the planetary action shaft (67) coaxially with the planetary axis, being either spur (S6) or bevel (B6) and cooperating with the action satellite (S5 or B5, respectively), with a teeth number Z.sub.S6 or Z.sub.B6, respectively, while the action sun (S8 or I8) cooperates with an eighth gear (S7), named “action sun-planet”, being such a gear as to properly cooperate with the action sun (S8 or I8), with a teeth number Z.sub.S7, which is rigidly connected coaxially with the planetary axis: either to the other end of the planetary action shaft (67), and therefore the planetary carrier (20) is either the output or the input of the compound planetary mechanism, while the relation which applies to all involved gears is: K*L=1, or to the planetary carrier (20), and therefore the planetary action shaft (67) is either the output or the input of the compound planetary mechanism, while the relation which applies to all involved gears is: (1−K)*L=1, where: K=Z.sub.S1/Z.sub.S2*Z.sub.S7/Z.sub.S8 or K=−Z.sub.I1/Z.sub.S2*Z.sub.S7/Z.sub.S8 or K=−Z.sub.S1/Z.sub.S2*Z.sub.S7/Z.sub.I8 or K=Z.sub.I1/Z.sub.S2*Z.sub.S7/Z.sub.I8 and: L=Z.sub.S3/Z.sub.S4*Z.sub.S5/Z.sub.S6 or L=−Z.sub.B3/Z.sub.B4*Z.sub.B5/Z.sub.B6, so that, the compound planetary mechanism transmits endless rotation from the action sun (S8 or I8), on the frame (00), to either the planetary carrier (20) or the planetary action shaft (67), on the central carrier (10), or vice versa, independently of the endless rotation of the central carrier (10) with respect to the frame (00).

12. A horizontal axis wind turbine with a compound planetary mechanism, according to claim 11, wherein the frame (00) is configured to be coincident with the stationary tower of the wind turbine and the central carrier (10) is configured to be coincident with the rotating nacelle of the wind turbine, and wherein either the planetary carrier (20) or the planetary action shaft (67) is the input of the compound planetary mechanism and is configured to be connected to the propeller shaft of the wind turbine, either via bevel gears or via any other means, while the action sun (S8 or I8) is the output of the compound planetary mechanism and is configured to be connected to the shaft of an electric generator, stationary with respect to the tower, either directly or through a gearbox, either on the top or on any other location of the longitudinal axis of the tower, so that an endless rotation is transmitted from the propeller shaft, on the rotating nacelle, to the shaft of an electric generator, on the stationary tower, independently of the endless rotation of the nacelle with respect to the tower, while, when the electric generator and possibly the gearbox are on the base of the tower or near it, the shaft which is configured to transmit endless rotation from the action sun (S8), which is located on the top of the tower, to the base of the tower or near it, preferably is an elongate space frame structure of sufficient strength and torsional rigidity, supported with bearing units in specific locations along the longitudinal axis of the tower and can also be used as a ladder for accessing the top of the tower.

13. A structure, stationary or movable in space, such as a building or an excavator or a battle tank or a robot, which has, at least, two compartments with the capability of endless rotation of each compartment with respect to its neighboring one, with a compound planetary mechanism, according to claim 11, wherein the frame (00) is configured to be coincident with the one compartment of this structure and the central carrier (10) is configured to be coincident with the next compartment, so that an endless rotation is transmitted from a driving shaft, on the one compartment, to a driven shaft, on the next compartment, independently of the endless relative rotation between them.

14. A steering bracket of a vehicle, which supports an endlessly rotating drive wheel, wherein the steering bracket can be rotated about an axis preferably perpendicular to the axis of rotation of the drive wheel for the purpose of changing the direction of the vehicle, with a compound planetary mechanism, according to claim 11, wherein the frame (00) is configured to be coincident with the vehicle chassis and the central carrier (10) is configured to be coincident with the rotating steering bracket, so that an endless rotation is transmitted from a driving shaft, on the vehicle chassis, to a driven shaft, on the steering bracket, wherein the driven shaft finally drives the drive wheel of the vehicle, independently of the rotation, finite or endless, of the steering bracket with respect to the vehicle chassis.

15. A helicopter, or a propeller-driven aircraft, or a propeller-driven craft, or a wind turbine of any type, with a compound planetary mechanism, according to claim 11, wherein the frame (00) is configured to be coincident with the helicopter frame, or the aircraft frame, or the craft frame, or either the rotating nacelle of a horizontal axis wind turbine or the tower of the wind turbine in any other case, respectively, and the central carrier (10) is configured to be coincident with the rotating propeller hub, so that a rotation, finite or endless, is transmitted from a driving shaft, on said frame, to a driven shaft, on the endlessly rotating propeller hub, independently of the rotation of the propeller hub with respect to said frame, mainly for the purpose of the adjustment of the propeller pitch.

Description

[0051] The drawings present:

[0052] “FIG. 01”: a side view and the meridian section A-A of a mechanism with spur gears exclusively.

[0053] “FIG. 02”: a side view and the meridian section B-B of a mechanism with spur and bevel gears.

[0054] “FIG. 03”: an exploded oblique view of the same mechanism as in FIG. 01, where the planetary carrier has been rotated at a random angle, in order to present clearly the satellites.

[0055] “FIG. 04”: an exploded oblique view of the same mechanism as in FIG. 02, where the planetary carrier, also, has been rotated at a random angle, in order to present clearly the satellites.

[0056] “FIG. 05”: a side view and the meridian section C-C of a mechanism with spur and bevel gears, the reaction sun of which is an internal gear.

[0057] “FIG. 06”: a side view and the meridian section D-D of a mechanism with spur and bevel gears, the reaction sun and the action sun of which are internal gears.

[0058] “FIG. 07”: an oblique view and a meridian section of an application of the mechanism—using spur gears only for the main mechanism- to a wind turbine, which clarify the structural details of this application.

[0059] “FIG. 08”: an oblique view and a meridian section of an application of the mechanism—using spur and bevel gears for the main mechanism- to a wind turbine, which clarify, also, the structural details of this application.

[0060] “FIG. 09”: an oblique view (a) and a meridian section (b) of an excavator, as well as a close-up of the same meridian section (c), which can be, also, the meridian section of a battle tank, or even of a building such as a lighthouse or a rotating tower.

[0061] “FIG. 10”: an oblique view (a) and a meridian section (b) of a steering bracket unit, as well as its application to a purely military vehicle 8×8×8 (c), an extreme sport utility vehicle 6×6×6 (d) and a classic passenger car 4×2×2 with a normal steering angle (e) and an extraordinary one (f).

[0062] “FIG. 11”: an oblique view (a) and a meridian section (b) of the start of the power-train for a wind turbine or of the end of the power-train for a propeller-driven aircraft, an oblique view (c) and a meridian section (d) of the end of the power-train for a helicopter, and an oblique view (e) and a meridian section (f) of the end of the power-train for a propeller-driven craft; all these drawings refer to a propeller pitch adjustment mechanism.

REMARKS

[0063] the FIG. 01 and the FIG. 02 are sufficient for the complete understanding of the structure and the operation of the Compound Planetary Mechanism; however the FIG. 03 and the FIG. 04 clarify even more structural details, [0064] the FIG. 05 and the FIG. 06 give a rather shallow presentation of two more specific implementations, so in these drawings all the elements involved have the notation as in the FIG. 02, unless their notation is stated otherwise, [0065] because the shaft which carries the action sun (S8) does not carry any other gear, in the drawings this shaft is indicated with the same notation S8, [0066] for better understanding of all these drawings, where the elements are rigidly connected together, either are depicted as a single element or their cross-hatches are the same in density and angle.

[0067] Therefore, the Compound Planetary Mechanism has a frame (00), which conventionally is stationary in space or rigidly connected to a movable or temporarily stationary structure, and a first carrier, named “central carrier” (10), the axis of which is named “central axis”, and which is supported on the frame (00) and is able to rotate freely and endlessly about the central axis.

[0068] The Compound Planetary Mechanism has, also, a first spur gear, named “reaction sun”, being either external (S1) or internal (I1), rigidly connected to the frame (00) coaxially with the central axis and having a teeth number Z.sub.S1 or Z.sub.I1, respectively, and a second spur gear, named “action sun”, being either external (S8) or internal (I8), supported on the frame (00) coaxially with the central axis and able to rotate freely and endlessly about the central axis, constituting either the input or the output of the Compound Planetary Mechanism and having a teeth number Z.sub.S8 or Z.sub.I8, respectively.

[0069] The central carrier (10) has a plurality of axes, each of them named “planetary axis”, preferably parallel to the central axis and at a distance from the central axis common for all the planetary axes, preferably equally angularly distributed around the central axis.

[0070] A second carrier (20) corresponds to each of these planetary axes, named “planetary carrier”, which is supported on the central carrier (10) coaxially with its corresponding planetary axis and is able to rotate freely and endlessly about this planetary axis, while each planetary carrier (20) has a plurality of axes, each of them named “satellite axis”, preferably parallel to this planetary axis and at a distance from this planetary axis common for all these satellite axes, preferably equally angularly distributed around this planetary axis.

[0071] A first shaft (45) corresponds to each of these satellite axes, named “satellite shaft”, which is supported on the planetary carrier (20) coaxially with its corresponding satellite axis, is able to rotate freely and endlessly about this satellite axis, and has a third gear, named “reaction satellite”, coaxially and rigidly connected to the one end of this satellite shaft (45), being either spur (S4) or bevel (B4) and having a teeth number Z.sub.S4 or Z.sub.B4, respectively, and has, also, a fourth gear, named “action satellite”, coaxially and rigidly connected to the other end of this satellite shaft (45), being either spur (S5) or bevel (B5) and having a teeth number Z.sub.S5 or Z.sub.B5, respectively.

[0072] A second shaft (23) corresponds to each of the planetary axes, named “planetary reaction shaft”, which is supported on the planetary carrier (20) coaxially with its corresponding planetary axis, is able to rotate freely and endlessly about this planetary axis, and has a fifth spur gear (S2), named “reaction sun-planet”, coaxially and rigidly connected to the one end of this planetary reaction shaft (23), cooperating with the reaction sun (S1 or I1) and having a teeth number Z.sub.S2, and has, also, a sixth gear, named “reaction satellite-planet”, coaxially and rigidly connected to the other end of this planetary reaction shaft (23), being either spur (S3) or bevel (B3), cooperating with the reaction satellite (S4 or B4, respectively) and having a teeth number Z.sub.S3 or Z.sub.B3, respectively.

[0073] A third shaft (67) corresponds, also, to each of the planetary axes, named “planetary action shaft”, which is supported on the planetary carrier (20) coaxially with its corresponding planetary axis, is able to rotate freely and endlessly about this planetary axis, and has a seventh spur gear (S7), named “action sun-planet”, coaxially and rigidly connected to the one end of this planetary action shaft (67), cooperating with the action sun (S8 or I8) and having a teeth number Z.sub.S7, and has, also, an eighth gear, named “action satellite-planet”, coaxially and rigidly connected to the other end of this planetary action shaft (67), being either spur (S6) or bevel (B6), cooperating with the action satellite (S5 or B5, respectively) and having a teeth number Z.sub.S6 or Z.sub.B6, respectively.

[0074] Depending on the design of the Compound Planetary Mechanism, in its generalized configuration, either any of the planetary carriers (20) or any of the planetary action shafts (67) constitutes either the output or the input of the Compound Planetary Mechanism—inversely depending on the role of the action sun (S8 or I8)—and is named “eccentric shaft” (20 or 67).

[0075] Therefore, the local angular velocity of this eccentric shaft (20 or 67) about its own axis with respect to the central carrier (10) is required to be independent of the angular velocity of the central carrier (10) with respect to the frame (00), while is required, also, to be only dependent on the angular velocity of the action sun (S8 or I8) with respect to the frame (00), and to achieve these requirements the teeth numbers of all the gears involved is necessary to satisfy the aforementioned “Independence Condition”.

[0076] More specifically, there are the following implementations of the Compound Planetary Mechanism: [0077] with the exclusive use of spur gears, exactly as shown in FIG. 01 and FIG. 03, where the only planetary carrier (20) is coincided with the eccentric shaft (20 or 67), while the Independence Condition is:

Z.sub.S7/Z.sub.S2*Z.sub.S3/Z.sub.S4*Z.sub.S5/Z.sub.S6*Z.sub.S7/Z.sub.S8=1, [0078] using spur and bevel gears, generally as shown in FIG. 02 and FIG. 04, where the only planetary action shaft (67) is coincided with the eccentric shaft (20 or 67), while the Independence Condition, generally, is:

(Z.sub.S1/Z.sub.S2*Z.sub.S7/Z.sub.S8−1)*Z.sub.B3/Z.sub.B4*Z.sub.B5/Z.sub.B6=1,

as well as in the case of merging of the two bevel satellites, which are rigidly connected to the satellite shaft (45), into a single bevel gear, exactly as shown in FIG. 02 and FIG. 04, where the Independence Condition is simplified as follows:

Z.sub.S7/Z.sub.S2*Z.sub.S7/Z.sub.S8=2, [0079] using spur and bevel gears, while the reaction sun (I1) is an internal gear and all the other gears are external, where the only planetary carrier (20) is coincided with the eccentric shaft (20 or 67) and the bevel satellites are merged into a single bevel gear, exactly as shown in FIG. 05, while the Independence Condition is:

Z.sub.I1/Z.sub.S2*Z.sub.S7/Z.sub.S8=1, [0080] using spur and bevel gears, while the reaction sun (I1) and the action sun (I8) are internal gears and all the other gears are external, where the only planetary action shaft (67) is coincided with the eccentric shaft (20 or 67) and the bevel satellites, also, are merged into a single bevel gear, exactly as shown in FIG. 06, while the Independence Condition is:

Z.sub.I1/Z.sub.S2*Z.sub.S7/Z.sub.I8=2.

[0081] Note: in all the above cases the Independence Condition is elegant and simple; however, special care should be taken so that the individual local transmission ratios do not lead to indeterminacy of the angular position of any moving part involved.

[0082] Thereafter, some more specialized applications of the Compound Planetary Mechanism are presented:

[0083] An interesting case, as it is already referred above, is its application to a horizontal axis wind turbine, so that the power generated on the horizontal propeller shaft is transmitted from the endlessly rotating nacelle, which, in fact, is the carrier (10) of the Compound Planetary Mechanism, on which it rests, to the stationary tower, which, in fact also, is the frame (00) of the Compound Planetary Mechanism, where this transmission is completely—kinematically and dynamically—independent of the endless rotation of the nacelle (10), a motion which is required so that the plane of rotation of the propellers takes the best possible orientation for the optimal exploitation of the available wind energy.

[0084] More specifically, these are two representative implementations: [0085] with the exclusive use of spur gears for the Compound Planetary Mechanism only, as shown in FIG. 07, where also is shown the way in which the horizontal propeller shaft transmits power to the only planetary carrier (20) of the Compound Planetary Mechanism, through bevel gears, [0086] using spur and bevel gears, as shown in FIG. 08, where also is shown, again, the way in which the horizontal propeller shaft transmits power to the only planetary action shaft (67) of the Compound Planetary Mechanism, also through bevel gears.

[0087] In all the above cases, if the electric generator and possibly the gearbox of the wind turbine are located on the base of its tower or near it, the shaft which has the duty to transmit power from the action sun (S8 or I8), which is located on the top of the tower of the wind turbine, to its base or near it, can be an elongate space frame structure of sufficient strength and torsional stiffness, supported with bearing units in specific locations along the longitudinal axis of the tower, which can also be used as a ladder for accessing the top of the wind turbine for inspection and maintenance purposes—after its secure immobilization, of course—at regular intervals.

[0088] Note: such a total transmission ratio must be achieved, so that the shaft, which undertakes to transmit power from the top of the tower of the wind turbine to its base or near it, rotates at a frequency sufficiently far from its natural frequency.

[0089] An application, also, of the Compound Planetary Mechanism, as generally shown in FIG. 09, is to a construction, which is either a building or any other structure with its base stationary with respect to the ground, such as a lighthouse or a rotating tower (the “OTE Tower” of the Thessaloniki International Fair, for example), or movable, such as a large excavator or a battle tank, the structure of which has, at least, two compartments with the possibility of endless angular motion of each compartment with respect to its neighboring one, where the one compartment of the structure, such as the ground or the chassis in these examples, is coincided with the frame (00) of the Compound Planetary Mechanism, while the next compartment, such as the tower or the turret in these examples, is coincided with the endlessly rotating central carrier (10) of the Compound Planetary Mechanism, with the final result of transmitting endless rotation from a driving shaft on the one compartment to a driven shaft on the next compartment, independently of the endless relative rotation between these compartments; of course this procedure can be repeated from the one compartment to its neighboring one, as many times as it is required by the number of the compartments.

[0090] More specifically, for an excavator there is the capability of carrying the engine and the hydraulic equipment in place B, as shown in FIG. 09(c), as currently happens, and in place A, as shown, also, in FIG. 09(c), can be the mechanical differential and the rest of the purely mechanical power-train in order to transmit power to the wheels, or the capability of carrying the engine—preferably a boxer one—in place A and the hydraulic equipment only in place B, keeping the gravity center in the lower possible level, thus rendering the use of this excavator more safe and effective.

[0091] Another application of the Compound Planetary Mechanism, as shown in FIG. 10, is to a steering bracket which carries the drive wheel of a vehicle, where this steering bracket is supported on the chassis of the vehicle and rotates about an axis preferably perpendicular to the axis of rotation of the wheel, for the purpose of steering the vehicle, so the transmission of power from the chassis which is coincided with the frame (00) of the Compound Planetary Mechanism to the endlessly rotating drive wheel of this vehicle is achieved, independently of the rotation of the steering bracket, which is coincided with the central carrier (10) of the Compound Planetary Mechanism; this steering rotation is usually finite, while, thanks to this configuration, can be also endless, rendering in this way the vehicle really holonomic.

[0092] As shown in FIG. 10(b) the output of the Compound Planetary Mechanism, which is the planetary carrier (20) of the FIG. 01, is connected to a coaxial splined shaft, thus constituting a telescopic transmission shaft of variable length, within a steering bracket frame of variable length as well, giving in this way one more degree of freedom to the wheel, while, with similar mechanical engineering tricks, the wheel can gain all the necessary degrees of freedom, so that the Compound Planetary Mechanism can supersede the ball-bearing constant velocity joint in many applications.

[0093] Finally, one more application of the Compound Planetary Mechanism, as shown in FIG. 11, is its use for the adjustment of the propeller pitch for a propeller-driven aircraft, a helicopter, a propeller-driven craft, but also a wind turbine, where the propeller hub is coincided with the endlessly rotating carrier (10) of the Compound Planetary Mechanism, and the aircraft frame, the helicopter frame, the craft frame, the rotating nacelle of the wind turbine in case of a horizontal axis type or the stationary tower of the wind turbine in any other case, is coincided with the frame (00) of the Compound Planetary Mechanism, while in this application the rotation for adjusting the propeller pitch may be even endless; for this application the configuration of the FIG. 06 has been used, with the two internal gears, since it results in the most compact and robust overall configuration.

Advantages

[0094] The basic configuration of the present invention includes only five moving parts, namely the action sun, the planetary action shaft, the satellite shaft, the planetary reaction shaft and the planetary carrier, with the addition, of course, of a sixth moving part, which is the central carrier; this central carrier, of course, already exists since the very beginning of the design and in fact is the moving part with the—in some way—undesired motion.

[0095] The operation of the basic configuration of the present invention, also, is based on the cooperation of only four pairs of cooperating gears, while all these gears can be and moreover is preferable to be standard ones.

[0096] Even more, there is no any other element which must be specialized; therefore the result is the simplest and most cost-effective possible construction and maintenance, while, at the same time, due to the least possible number of moving parts, the highest possible degree of efficiency is achieved, leading to the most productive possible operation.

[0097] It is also important that, by the design of the present invention per se, the most balanced arrangement of the diameters of the gears can be achieved, resulting in the avoidance of the problematic pinion, which is the weakest link in any power-train.

[0098] Moreover, taking into account some specific applications of the present invention, the advantages become more obvious and understandable: [0099] relocation of the vast majority of the operating elements of a wind turbine, from its rotating nacelle to its stationary tower, resulting in the drastic lightening of the nacelle and the drastic, also, reducing of the construction and maintenance costs, [0100] in addition, combining the concept of the application PCT/GR2021/000012 with the one of the present invention, the result is a configuration with a total transmission ratio as high as it is required by the design of the wind turbine as a whole, thus this configuration comprises a highly effective speed increaser, taking low speed from the propeller shaft and providing high speed to the electric generator, superseding the currently used speed increaser, and the achievement of all these is performed by the insertion of five new moving parts only, [0101] transmission of the electric power via the simplest possible way, avoiding an unnecessarily complex configuration, with low performance and short-lived elements, such as the electric slip rings, [0102] achievement of purely endless rotation of the turret of a large excavator or a battle tank, with respect to their chassis, while with the existing technology either the rotation is finite and with a significantly shorter angular path than a full revolution or it is much more expensive in construction and maintenance if an endless rotation is available but with a special sealing for rotation of the hydraulic piping, [0103] lowering of the level of the gravity center of the excavator or the battle tank as much as possible, thus rendering the use of the excavator or the battle tank more effective and safe, [0104] designing of an all-wheel drive and all-wheel steering vehicle, a really holonomic one, as the steering brackets can be rotated, for steering, in an absolutely endless way, [0105] designing, also, of a vehicle with extremely high clearance from the ground, for special use—for firefighting in rugged and jungly terrain, for instance—as the height of each steering bracket unit can be as great as it is required, [0106] achievement of the capability of transmitting of a huge amount of power via wheels which propel and steer the vehicle at the same time, even in a classic front-wheel drive car, with a normal steering angle amplitude, because this transmission is performed via robust gears instead of delicate balls of the ball-bearing constant velocity joint, a fact that can render this application of the present invention the new and promising proposal for the propulsion of a vehicle of any type, especially a military one or even a supercar, [0107] achievement of the most elegant, compact and robust configuration, even in the case of the propeller pitch adjustment, although the currently used mechanisms are effective because of the need of finite operating stroke, rotational or linear, [0108] achievement of the capability of even endless rotation for the adjustment of the propeller pitch, with whatever this implies.

[0109] In conclusion, these are a number of merits of the present invention which are easily contrasted as advantages over a competition, which in fact does not exist, or, in the few and individual cases in which it does exist, is rather moderate.