WO2009107059A1

WO2009107059A1 - Actuator for power transmission

Info

Publication number: WO2009107059A1
Application number: PCT/IB2009/050736
Authority: WO
Inventors: Giancarlo Cioffi
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-02-25
Filing date: 2009-02-24
Publication date: 2009-09-03
Anticipated expiration: 2010-08-25
Also published as: EP2260218A1; ITPI20080012A1

Abstract

Unit constituted by a thrusting element 1 able to deliver a predetermined force and at least a receiving element 2. The receiving element 2 is placed on a path 3 on which it is constrained to slide, for example through rollers. A rod 4 is pivoted in a predetermined point 5 in a way to rotate dragging the area comprised between the track and the same rod. The thrusting element is connected to the rod 4 in a way to induce it to rotate. The rotation of the rod 4 forces the receiving element to move along the path towards the hinge decreasing the arm of the lever and increasing proportionally the force that receives. According to a preferred solution of the invention, the thrusting and the receiving elements are two actuators constituted by a piston and a cylinder. It is then comprised a returning motion that brings back the receiving element into the initial configuration.

Description

ACTUATOR FOR POWER TRANSMISSION

DESCRIPTION

Technical Field

The present invention refers to the technical field of mechanic for the transfer of a power, and in particular it refers to a unit able to transfer a predetermined power to user elements.

State of the Art Nowadays are known actuators, or units in general, of different^' kind able to transmit a predetermined force to components that have to move.

For example, are known actuators of traditional type and commonly used, generally constituted by an external cylindrical body within which it is assembled a sliding piston. The movement of the piston can happen by means of a fluid in pressure that gets injected in the cylinder. Depending on the needs, it can be used air, oil, a mixture of both or also other kinds of fluids. In the case of oil-pressure, the piston is moved thanks to the aid of oil in pressure injected inside the cylinder through an entry hole. In this way the piston, thanks to the thrust action of the injected oil, moves along the cylindrical site applying this way a predetermined force on the element with which is connected. The thrust force will depend obviously on both the pressure with which the oil has been injected inside the same cylinder and on the dimensions of the piston. Indeed by changing the area of the piston on which the oil presses, will proportionally change the force with which the same piston raises and, consequentially, the force acting on the external element to which it results to be connected.

Generally, then, the return motion of the piston inside the cylinder will determinate the exits of the oil through an apposite discharge hole to be then directed in a container. In this manner it is possible to create a closed circuit of re-circulation. The actuators, along to the re-circulation circuits that allow their functioning, are then commonly used for different aims that are found from the aeronautics field up to the mechanics one. For example, the actuators of oleodynamic type are commonly used in the aeronautics field in order to move the controlling surfaces of the aircraft. In such case a simple impulse controls the entering of the oil in pressure inside the chamber of the cylinder forcing this way the piston to slide in its inside for a predetermined quantity, moving this way the surface to which it is connected.

However such devices have a big inconvenient. The power transmissible through the injection of the fluid in pressure is limited and, as a consequence, the exiting power is amplified to an extremely limited factor. This implies that the realization of powerful actuators requires big and expensive plants. According then to their dimensions the uses a strongly limited.

Nowadays, thus, we try to overcome to said inconvenient through opportune dimensioning of the piston's surface on which the oil pushes, it will be allowed to obtain the desired force through which the surface is moved. Obviously, by changing then the pressure of the oil entering inside the cylinder, it will be possible to manage and change the force applied by the piston within a pre-fixed range.

However, once a piston is dimensioned for a particular use, the only way to change the force applied by the piston is to change the input pressure of the oil inside the cylinder. This, obviously, implies the inconvenient that it is necessary to create a device that pressurizes the oil in a variable manner and moreover, that is able to reach elevated pressure values.

Thus in the case are necessary high values of pressure it is required to have big and expensive pressurizing means of the oil. The sole manner to contain as much as it is possible this inconvenient is to find a compromise between the superficial dimensions of the piston and the pressure values with which the oil is injected inside the cylinder.

However not always this compromise is obtainable, especially when the forces that require to be developed by the piston must be elevated. The only thing that is possible to do in this case is to reduce the dimensions of the piston as much as possible, but obviously not over a certain limit of sub-dimensioning over which it is possible to easily incur into breakings.

The problem is equivalent and remains the same also in the case where the actuator is not of oleodynamic type but of hydraulic type, compressed air or mechanical with springs and similar.

Disclosure of invention

It is therefore the aim of the present invention to give a unit that provides to these lacks and allows to resolve the above mentioned inconvenient.

In particular it is the aim of the present invention to give a unit that allows to obtain high values of exiting force without having to require both big plants of fluid pressurizing and big elastic elements of thrust. It is also the aim of the present invention to give a unit that is economic and versatile in its uses.

These and other aims are reached through the present unit for the movement of devices and/or power transmission in general, characterized by the fact to comprise: - At least an thrusting element (1) able to supply a predetermined force;

- At least a receiving element (2) to receive the force supplied by the thrusting element; - A transmission element (4) interposed between the thrusting element and the receiving element, said transmission element being assembled in a rotating manner (5) in such a way to transfer by means of one of its rotation the force from the thrusting element (1) to the receiving element (2);

- A path (3) of predetermined slope; and where the receiving element (2) is assembled in a sliding way between the transmission element (4) and the path (3) so that the rotation of the transmission element (4) causes the movement of the receiving element (2) along the path (3) by moving from/towards the rotation hinge (5) undergoing this way a variable force during the motion.

The sliding bond that is realized at the receiving element 2 to connect it to the path 3 and to the transmission element 4, allows thus to move it along the path in correspondence to the rotation of the transmission element 4. The thrusting element 1 acts therefore on the element 4 and causes the rotation of the same Given the slope of the path, the ascent motion determines a squeezing of the receiving element 2 that is incremented during its approaching motion towards the hinge 5. The returning motion brings gradually back the element 2 to its initial condition. It is thus clear how the receiving element gets squeezed in the forward motion with a force that is always proportionally increasing. The advantageous of such solution and the use of the same are therefore many and hereinafter specified.

Advantageously the transmission element (4) comprises a rod (4) or similar. Such solution makes easy the rotating connection of the same to the receiving element.

According to a first possible solution of the invention, the thrusting element (1) comprises a first (1) actuator while the receiving element (2) comprises a second actuator (2) .

In particular the first actuator (1) comprises a cylinder (I' ) and a piston (I' ' ) and said second actuator (2) comprises a cylinder (2') and a piston {2'') sliding inside said cylinder. The actuator thus can be of any kind, as for example of oleo dynamic type. According to such solution the cylinder (l^f) acts the thrusting force on the transmission element (4) by means of the extraction or retraction of the sliding piston (I' ' ) and, as a consequence, the receiving body (2) is forced to move along the path (3) retracting and extracting its respective piston (2' ' ) .

In particular, in order to make the entire unit functioning, the cylinder (I' ) comprises at least an entrance for a working fluid and the cylinder (2' ) comprises at least an exit for a further working fluid.

In this manner the entering of the fluid under pressure inside the cylinder (1') controls the movement of the piston (1'') while the movement of the piston (2'') controls the exits at the corresponding pressure of the fluid from the cylinder (2' ' ) .

It is thus clear how such above mentioned force increasing allows according to such solution to have in an easy way a fluid exiting from the receiving element at an incrementing increasing pressure. Such fluid under pressure can then be used in different manners.

Advantageously the path (3) has a parabolic type course.

According to other possible solutions, the path (3) has a circumferential arch shape. The solutions of predisposition of the elements (1, 2) can then be different. According to a first possible solution the transmission element (4) is pivoted (5) in correspondence of one of its free ends. In such case, then, the thrusting element (1) is placed above the receiving element.

According to another possibility, the transmission element is pivoted (5) in correspondence of a point internal to its length. In such case, then, the thrusting element (1) is placed alongside respect to the receiving element.

The thrusting element and the receiving element do not necessarily have to include actuators of oleo dynamic type or similar. Alternative solutions comprise, always with the same solution of predisposition as described above, a thrusting element and a receiving element both of elastic type able to cede and store energy by means of the overall variation of their length.

In such case then the elements of elastic type comprise a compression spring.

Alternatively the elements of elastic type can comprise respectively two plates elastically flexible.

Alternatively are possible combinations of receiving elements of elastic and thrusting type of oleo dynamic type and vice versa.

According to the described solutions, the path 3 can equally be configured as a track.

In all the described configurations the first actuator (1) is generally assembled in a fixed position. In order then to allow the movement of the second receiving element (2) respect to the path, also in the case of the track, it comprises rotating elements (6) .

Advantageously the rotating elements (6) are rollers.

A particular innovated shape of the invention corαprises also that the receiving element (2) comprises motion transmission means (13, 14) .

Such motion transmission means comprise at least a toothed wheel (14) assembled rotating in a neutral manner on the receiving element.

According to such solution it is also comprised at least a toothed rack (13) assembled parallel to said predefined path (3) and within which it is coupled said toothed wheel (14), in such a manner that during the motion of the second actuator (2) along said path (3) said toothed wheel (14) rolls on said rack (13) .

It is clear the utility of such solution that allows to directly transform in a rotational motion the translation of the receiving element. This allows then to use such rotation for example by moving it to a shaft.

Advantageously it can be comprised also a container

(10) and an alternator, said container receiving the fluid under pressure exiting from the receiving element (2) to feed said alternator. In this way it is possible to produce electric current.

It is also clear, for the aims of the present invention, how the oscillation motion induced to the transmission element 4 can be continuous or alternated.

Brief description of drawings

Further features and advantages of this actuator, according to the invention, will be clearer with the description that of one of its pattern realization that follows, made to illustrate but not limit, with reference to the annexed drawings, in which:

- The figures from 1 to 3 represent in view the functioning phases of the newfound according to the invention.

- The figures from 4 to 6 represent in view the functioning phases of the newfound according to a particular preferred solution.

- figure 7 schematically represents a possible application of the invention. - figure 8 schematically represents a further possible application of the invention.

Description of a preferred pattern realization

With reference to figure 1 it is described the unit for the movement of devices and/or the transmission of power according to the invention.

Structurally, in the most essential aspects, the invention comprises a thrusting element 1, able to deliver a predetermined power, and a receiving element 2 suitable to receive and thus to store such power. Such elements are interposed to a transmission element 4 which is assembled rotating respect to a rotation hinge 5. A path 3 of predetermined slope constitutes a supporting base for the receiving element 2. In particular, the receiving element 2 is assembled sliding along the transmission element 4 and respect to said path 3. According to what has been described, thus, the receiving element results to be positioned between the path 3 and the transmission element 4 and it is configured in such a way to be induced from the rotation of the transmission element 4 to move along the path. In particular the element 2 is able to move along the path towards the hinge 5 and move apart from it, during the entire oscillating motion of the element 4. In such manner the receiving element 2 gets closed to and moves apart from the hinge point, or rather from the point of greatest application of the power being this way affected by a variable compression force during its entire movement.

By getting into more detail of the invention, the figure 1 shows a possible preferred solution. According to such configuration the thrusting element 1 comprises a first actuator 1 and the receiving element 2 comprises a second actuator both functioning with fluids as air, oil and similar and well known in the prior art. The actuator 1 comprises thus a cylinder 1' and a piston V ' sliding in its inside while the actuator 2 comprises its relative cylinder 2' and piston 2' ' . In particular, only as a non limitative example, it has been chosen in the figures an actuator of oleo dynamic type, which functions thanks to the action of the oil injected inside the cylinder under pressure. Obviously any other type of actuator can be easily chosen.

The actuator 1 is placed in a fixed manner respect to a generic supporting frame and it has at least the entry hole for the entering of the oil under pressure. In this well known manner, it is thus possible to move the piston 1' ' causing its exit or its retroaction thanks to the injection of the oil under pressure. Generally it is also comprised an exit hole that allows the return of the same oil.

Still according to the first solution of the invention, the transmission element 4, for example a simple rigid rod 4 or indifferently a plate of sufficient rigidity or similar, is hinged in the rotating point 5 corresponding to its free end. The end opposite to the rod is then connected to the piston 1' ' . According to such preferred solution of the invention, the actuator 1 is fixed upper than the path 3 and the second actuator placed on the path, m The hinge 5 allows then to the rod to rotate around it "dragging" this way a predetermined area during its entire rotation. Figure 1 indicates the distance d between the positioning of the first actuator 1 and the hinge 5. As already said, the second actuator 2 is placed under the first one, on the path 3 defined in the initial solution. The path 3 can be indifferently a parabolic arc, a circle arc or similar or simply have a certain slope. The initial distance between the second actuator and the hinge can be any, but for reasons of simplicity it has been chosen to position it at the same distance d of the first actuator in its initial configuration.

The second actuator 2 comprises (still as described in figure 1) , in correspondence of its base, rollers or similar in order to slide on the path 3. Alternatively it is possible to comprise the rollers exactly as if they were gears on which the piston slide. Between the different possible solutions, too help the maintenance of the position of the actuator 2 along the path, it can be possible to realize the path as a train track on which the rollers of the actuator 2 slide (look at figure 8) .

In order to make the second actuator 2 slide respect to the path it is necessary to slidably constrain it also respect to the rod 4 in such a way that it can move forward along the path 3 without remaining constrained in the point where gets in contact with the rod. For such reason simple rotating elements 6 as in figure 1, as spheres or rollers, are placed at the upper end of the piston, accomplishing to such function. Types of different sliding connections can be easily used, without having to move apart from the present inventive concept.

A second preferred solution of the invention comprises on the other hand (look at figure 4) the rod 4 hinged in a predetermined point along its length, preferably in a middle point 5. In such way the positioning of the first actuator 1 is not anymore on top of the second actuator, but along its side.

For both the described solutions, it is possible to supply the actuator 2 with motion transmission means (13, 14) . In particular (look at figure 8) a toothed wheel 14 is assembled rotating in neutral on the actuator. In this manner, by comprising a simple rack 13 placed practically parallel to the path 3 and within which couple the toothed wheel, it can be used the motion of the actuator 2 to make the wheel rotate exactly as a car wheel as will be better explained later on. In such case it is more convenient to use the solution with the sliding wheels placed under the toothed wheel shaped actuator and the hinge shaped path. It is indeed better synchronized the rotation of the wheel 14 with the sliding of the actuator.

Furthermore for both the preferred solutions of the invention it is also possible to comprise a container 10 and an alternator configured in a way to use the exiting energy that has been obtained from the second actuator. Also this second further option will be better explained after on.

Having thus described structurally in the most essential aspects the invention, it is now described the functioning of the unit. The description of the functioning refers only to the first preferred solution exclusively for reasons of descriptive simplicity, as it results to be similar also for the other configurations. Figure 1 shows the initial condition where the piston 1' ' starts to transmit by means of the rod 4 its force F to piston 2' ' . As said, for such reason, it is injected a fluid under pressure inside the cylinder V as in the prior art. The transmission of the force from the first actuator happens thanks to the thrust of the actuator 1 that acts against the rod 4, creating this way a torsional moment M. In such manner the rod is forced to rotate around the hinge 5.

According to such described solution, the piston 1 is fixed and thus the moment M created by it on the rod is constant. In any case, without moving apart from the present inventive concept, it can be used a variable moment M by simply translating during the functioning the position of the actuator 1.

The piston 2' ' undergoes thus to a force Fi given by the pressure action of the rod. In particular the initial condition chosen exclusively as an example in figure 1 shows a force Fi substantially coinciding with F, as the initial distance d of positioning for the two actuators is equal. Because of the pressure action, the piston 2'' will this way start to retract inside the cylinder forcing the oil found inside the cylinder 2' to exit at a predetermined pressure. The actuator 2 is preferably, but not necessarily, placed according to an initial β angle. In such manner, the light initial positioning slope makes the force Fi to which it undergoes, decomposable into a component that is perpendicular to the path FN and into a tangent component FT which will cause its raising along the path inside, thus, the area defined between the same path and the rotating rod (look for such reason figure 2) . Obviously a small percentage of FT will be dispelled into friction given by the contact with the track. In any case, even if such initial predisposition according to an angle β helps the start, nothing would stop to place the second piston 2 perfectly in axis with piston 1. In such case, then, the starting action can be indifferently guaranteed by the simple pressure and haulage action of the rod as also from eventual similar means that, when required, can realize the above mentioned initial starting slope.

The ascent of the actuator 2 along the path (look at figure 2), changes, more precisely decreases, the lever distance di of the point where the force resulting Fi is applied respect to the hinge 5. As a consequence, with equal moment M applied to the rod 4 by the actuator 1, will increase proportionally the force Pi acting on the second actuator as the arm decreases. The returning motion resets the initial condition. This is thus an increase of both the ascent tangential force FT and of the force Fv with which the piston re-enters and compress the oil during the forward motion towards the hinge 5. The exit pressure of the oil inside the second actuator is thus greatly increased during the entire ascent motion.

In figure 3 it is highlighted an ascent phase that is almost finished, where the actuator 2 is almost on top of the path 3 and, correspondingly, the piston 2' ' is almost totally retracted inside its cylinder 2' . During the ascent, the arm of the lever will continue to change from a value di relative to a rotational angle θi of the rod 4 to a value d2 relative to a rotation Θ2 , continuing to proportionally increase the resulting force Fi.

Figures from 4 to 6 describe the functioning relative to the second preferred solution of the invention. In such case the rotation of the hinged rod in the mid point determines the motion of the second actuator along the ascent plane.

The capability and the possibility of use of the present invention are thus clear and notable. Indeed, differently from a normal actuator, this combination of elements makes possible to amplify the exiting force without having to use big devices that inject the oil under pressure at increasing values inside the cylinder 1' .

A possible example of use of the present invention is represented in figure 7. In this case the oil under pressure that exits from the actuator 2, with increasing pressure values, is used to move an alternator 11 connected to a container 10, to produce electric current. Alternatively the oil under pressure that exits from the cylinder 2^r ' can be used in the traditional manner to move some objects or surfaces in general.

Other uses allow to use the oil under pressure exiting from the second actuator for different aims.

Nothing would anyway avoid, without having to move from the present inventive concept, to use as thrusting element not only actuators, but equivalent elements able to create a thrusting action on the rod 4. In particular it can be used elements of elastic type as springs or even more an inflexed plate which induces on the rod 4 an elastic thrusting force that is exactly as a compression spring. Alternatively, to move the rod 4, it can be used also an engine. Equally, the receiving element do not necessarily have to be an actuator, but any other body that can store the incremental force Fi to be then re- used. Just as an example, the actuator 2 can be substituted with a compression spring or with an inflexed plate. The compression force Fi stored by the element of elastic type can then be used exactly as the oil under pressure in the case of actuator. The dimensions of the actuators can be any, but, according to the preferred solution of the invention, it has been chose to use actuator that have equal volumes and such for which the stroke of the piston 1' is double respect to the one of piston 2' ' . The above description of a specific shape is able to show the invention from the conceptive point of view, in a way that others, by using the art, can modify and/or adapt in different applications this specific shape without any further research and without going apart from the inventive concept, and, therefore, it is intended that these adaptations and transformations will be considered as equivalent to this specific realization. The means and materials to make the many described functions can be of various nature without exiting the area of the invention, it is intended that the expressions or the terminology used have a simple descriptive aim and therefore not limiting.

Claims

1. Unit for the movement of devices and/or the transmission of power in general characterized by the fact to comprise:

- At least an thrusting element (1) able to supply a predetermined force;

- At least a receiving element (2) to receive the force supplied by the thrusting element; - A transmission element (4) interposed between said thrusting element and said receiving element, said transmission element being assembled in a rotating manner in such a way to transfer by means of one of its rotation the force from the thrusting element (1) to the receiving element (2);

- A path (3) of predetermined slope; and where the receiving element (2) is assembled in a sliding way between said transmission element (4) and said path (3) so that the rotation of said transmission element (4) causes the movement of said receiving element (2) along said path (3) by moving from/towards the rotation hinge (5) of the transmission element and undergoing this way to a variable force along the path.

2. Unit for the movement of devices and/or the transmission of power in general, according to claim 1, where said transmission element (4) comprises a rod (4) or similar.

3. Unit for the movement of devices and/or the transmission of power in general, according to claim 1, where said thrusting element (1) comprises a first actuator (1) and said receiving element (2) comprises a second actuator (2) .

4. Unit for the movement of devices and/or the transmission of power in general, according to claim 3, where said first actuator (1) comprises a cylinder (l^f ) and a piston (1'') and said second actuator (2) comprises a cylinder (2' ) and a piston {V ' ) sliding inside said cylinder.

5. Unit for the movement of devices and/or the transmission of power in general, according to claim 3, where said cylinder (1') acts said thrusting force on said transmission element (4) by means of the extraction or retraction of the sliding piston (1'') and said receiving body (2) is forced to move along said path (3) retracting or extracting its respective piston (2i'r i

6. Unit for the movement of devices and/or the transmission of power in general, according to claim 3 and 4, where said cylinder (1') comprises at least an entrance for a fluid and the cylinder (2' ) comprises at least an exit for a fluid in such a way that the entrance of the fluid within the cylinder (I' ) controls the movement of the piston (1'') while the movement of the piston (2'') controls the exit under pression of the fluid from the cylinder (2'') .

7. Unit for the movement of devices and/or the transmission of power in general, according to claim

1, where said path (3) has a parabolic shape.

8. Unit for the movement of devices and/or the transmission of power in general, according to claim 1, where said path (3) has a circonferential arch shape .

9. Unit for the movement of devices and/or the transmission of power in general, according to claim

1, where said transmission element (4) is pivoted (5) in correspondence of one of its free ends.

10. Unit for the movement of devices and/or the transmission of power in general, according to claim 1 and 8, where the thrusting element (1) is placed above the receiving element.

11. Unit for the movement of devices and/or the transmission of power in general, according to claim

1, where said transmission element is pivoted (5) in correspondence of one of its points located within its length.

12. Unit for the movement of devices and/or the transmission of power in general, according to claim 1 and 10, where the thrusting element (1) is placed alongside respect to the receiving element.

13. Unit for the movement of devices and/or the transmission of power in general, according to claim 1, where said thrusting element and said receiving element are both of elastic type able to cede and store energy by means of the overall variation of their length.

14. Unit for the movement of devices and/or the transmission of power in general, according to claim 13, where said elements of elastic type comprise a compression spring.

15. Unit for the movement of devices and/or the transmission of power in general, according to claim 13, where said elements of elastic type comprise respectively two plates elastically flexible.

16. Unit for the movement of devices and/or the transmission of power in general, according to one or more of the previous claim, where said trusting element (1) is assembled in a fixed position.

17. Unit for the movement of devices and/or the transmission of power in general, according to one or more of the previous claims, where said receiving element (2) comprises rotating elements (6) or similar able to slide along said path .

18. Unit for the movement of devices and/or the transmission of power in general, according to claim

17, where said rotating elements (6) are rollers.

19. Unit for the movement of devices and/or the transmission of power in general, according to one or more of the previous claim, where said second actuator comprises motion transmission means (13, 14) .

20. Unit for the movement of devices and/or the transmission of power in general, according to claim 19, where said motion transmission means comprise at least a toothed wheel (14) assembled rotating in a neutral manner.

21. Unit for the movement of devices and/or the transmission of power in general, according to claim

19 and 20, where it is comprised at least a toothed rack (13) assembled parallel to said predefined path

(3) and within which it is coupled said toothed wheel (14), in such a manner that during the motion of said second actuator (2) along said path (3) said toothed wheel (14) rolls on said rack (13) .

22. Unit for the movement of devices and/or the transmission of power in general, according to one or more of the previous claims, where it is also comprised a container (10) and an alternator, said container receiving the fluid under pressure exiting from the receiving element (2) to feed said alternator.