KR20090029215A - Constant speed drive system for gimbal-mounted rotor hubs - Google Patents

Abstract

The present invention relates to a constant velocity drive system for a rotorcraft aircraft rotor comprising a differential torque distribution mechanism and a gimbal mechanism. A rotorcraft aircraft is disclosed that includes a rotorcraft aircraft rotor that includes a differential torque distribution mechanism and a gimbal mechanism.

Description

CONSTANT-VELOCITY DRIVE SYSTEM FOR GIMBALED ROTOR HUBS}

TECHNICAL FIELD The present invention relates to the field of rotorcraft aircraft having a gimbal mounted rotor hub.

There is an increasing demand for rotorcraft aircraft that provide greater thrust and faster speeds and support larger loads and / or heavier fuselage. For example, there is a need for more powerful tilt rotor aircraft. Of course, if the performance criteria as listed above are increased, then the functional system of the rotorcraft must be improved to achieve the desired performance improvement. Rotor hub drive systems are one of a number of functional systems that need to be retrofitted to meet the demand for improved rotorcraft performance.

Rotor hub drive systems are often or include constant speed drive systems or homokinetic drive systems that have been in use for a very long time. There are many successful configurations of constant speed drive systems for various types of rotorcraft. The constant velocity drive system is usually configured to transmit torque or rotational force from the first rotating member to the second rotating member, wherein the first rotating member may not be coaxial with the second rotating member. The constant speed drive system is well suited for use in rotary wing aircraft as a means of torque transmission from the rotating mast to the rotor hub, especially when the rotor hub is gimbally connected to the rotating mast. These two constant speed drive systems are taught in US Pat. No. 6,712,313 to Zoppitelli et al.

Chopitelli et al. Have two torque gimbal devices (such as Chopitelli et al.) In which a torque distribution mechanism (see US Patents 2-6 of Chopitelli et al.) Is used to drive and tilt the rotor hub (relative to the mast). And a first constant velocity drive system associated with the patent (see FIGS. 7 and 8). In addition, Chopitelli et al., The rotor hub are gimbally connected to the mast by gimbal means (see US Pat. Nos. 9 and 10 of Chofitelli et al., Above) comprising half of a flapping thrust bearing. And a same torque distributing mechanism teaches a second constant velocity drive system that drives the rotor hub in rotation via a drive link. In a second constant velocity drive system, the differential torque distribution mechanism drives the hub in rotation via a drive link, while the hub is connected to the mast using tilting means including a flapping thrust bearing.

Referring now to FIG. 1, there is shown a tilt rotor rotorcraft incorporating a constant velocity drive system as taught by Chopitelli et al. Tiltrotor aircraft 17 is shown in an airplane mode of flight operation. When aircraft 17 is in airplane mode, wings 19 (only one shown) are used to float fuselage 21 in response to the action of rotor system 23 (only one is shown). The rotor blades of the rotor system 23 are not shown. Each of the two nacelles 25 (only one shown) substantially surrounds the constant velocity drive system 27 and thus obscures the constant velocity drive system 27 in the figure of FIG. 1. Of course each rotor system 23 is driven by an associated engine (not shown), one engine is housed inside each nacelle 25.

Referring now to FIGS. 2-6, Chopitelli et al. Employ a differential torque distribution mechanism that is assembled to a rotor mast for rotationally driving a hub of a convertible aircraft tiltrotor as described above with reference to FIG. 1. Teach

2 to 6, the mast 29 of the rotor, which is driven by a base (not shown) around the longitudinal axis ZZ in rotation, supports a differential mechanism, indicated generally by 31 . This mechanism 31, which belongs to the constant velocity drive means of the rotor hub, consists mainly of an assembly of three disks which are coaxial about an axis ZZ and along which one disk is disposed on another disk. Of the central disk 33 is disposed axially between the other two disks 35 and 37, one of the other two disks being axially between the central disk 33 and the seating shoulder 39. And a radially annular periphery projecting outward on the shaft or mast 29, which is disposed along the axis ZZ at the proximal end of the mast 29 and thus toward the interior of the switchable aircraft structure. While referred to as the inner disk 35, a third disk 37 called the outer disk is disposed between the central disk 33 and the axial preload device in the axial direction. And the assembly of the three disks (33, 35 and 37) preloaded under a preload condition reason to be assembled along the threaded portion of the mast (29) described later are laminated in the axial direction (in accordance with ZZ).

The central disk 33 is integrally made to rotate with the mast 29 by an axial inner spline 43 in the central bore, the spline being an axial outer spline on the cylindrical spline portion 29a of the mast 29. And torque to transmit it. As can also be seen in FIG. 7, the central disk 33 has a central portion 45 between two cylindrical journals 47 and 49 at the axial ends, the central portions being side by side and parallel in axis. Two cylindrical bores 55 extend radially outwardly by four spider arms 51 drilled, respectively. The four spider arms 51 are opposite each other and are uniformly distributed over the circumference of the central portion 45 of the central disk 33.

The inner disk 35 and the outer disk 37 include respective circumferences 57 and 59, respectively, the circumferences being axially offset toward the center 45 of the central disk 33 and the axial inner journal. An inner disk 35 and an outer disk, each enclosing an axially outer journal 49 (an upper journal in the drawing) of the central disk, each of which projects radially outwardly, respectively; Perimeters 57 and 59 of 37 are also provided with four spider arms 61 and 63, respectively, which are also oppositely opposite each other and around the perimeters 57 and 59, respectively. Uniformly distributed throughout, each spider arm also has two bores 65 and 67, each having the same diameter as the bores 55 in the central disk 33 while also having parallel and parallel axes.

In addition, the two drive pins 69 are circular in shape and generally cylindrical in shape and include their axes in the radial plane [relative to the axis ZZ] and project toward the outside of the inner disk and occupy opposite positions. Supported by an inner disk 35, each drive pin being located between two spider arms 61 of the inner disk 35 and axially offset towards the center 45 of the central disk 33 at the same time, These drive pins can thus be accommodated in one of the cuts defined around the center 45 of the central disk 33 between the two spider arms 51 of the disk 33 (see FIGS. 5 and 6). ). Similarly, the outer disk 37 has the same cylindrical shape with a circular cross section, is the same size as the pin 69 and is oppositely opposite and protrudes outward of the circumference 59 of the disk 37. At the same time, two drive pins 71 are provided which are axially offset towards the center 45 of the central disk 33, so that these drive pins are respectively provided on the spider arm 51 around the central disk 33. Alternating in the circumferential direction about an axis common to these three disks 33, 35 and 37 together with the drive pins 69 of the inner disk 35, which can be accommodated in one of the four cuts defined by it.

The three discs 33, 35 and 37 are arranged axially one on top of the other so that the spider arms 51, 61 and 63 are stationary, as shown in the figure in the left half in FIG. In the state, located directly above each other, the bores 55, 65 and 67 are arranged between one disk and the other, so that each of the eight groups of three bores 55, 65 and 67 arranged in this way As shown in FIG. 2, the axes ZZ of the mast 29 are radially distributed in two oppositely opposite directions along the two radial planes perpendicular to each other and uniformly distributed on four pairs of connecting pins 73. In the four assemblies of the two neighboring connecting pins 73 at the same distance from each other, eight connecting pins 73 distributed in the above-described manner over the circumference of the three disks can each be accommodated.

Each connecting pin 73 has a geometric longitudinal axis AA substantially parallel to the axis ZZ of the mast 29, with each connecting pin having three balls centered on the axis AA. Each of the joint connections 75, 77, and 79 is hingedly connected to each of the three corresponding spider arms 51, 61, and 63. As shown in the right half of FIG. 4, each connecting pin 73 has a triple diameter in which the diameter of the central ball joint 81 is larger than the diameter of two end ball joints 83 having the same diameter. Pins with ball joints, each of which ball joints 81 and 83 are cylindrically stacked bearings 85 (bearings for central ball joint connections 75) and cylindrically stacked bearings 87 (each end ball Bearings for joint connections 77 and 79] and are laminated ball joints held radially [relative to axis AA], and cylindrically stacked bearings 85 and 87 are corresponding connection pins 73. It is substantially coaxial about its geometric axis AA. For this reason, each connecting pin 73 is in the form of a cylindrical sleeve when viewed from the outside, the other one being slightly spaced apart from one another on one pin and having a radial collar at the top (see FIG. 7), each of which has a shaft ( It is divided axially into three parts surrounding three ball joint connections 75, 77 and 79 offset along AA).

After the eight connecting pins 73 are installed, the central disk 33 which rotates integrally with the mast 29 is a drive disk for the inner disk 35 and the outer disk 37, and the inner disk and the outer disk. Are driven disks of the mechanism 31 and these disks are each hingedly connected to the hub by means of two corresponding drive pins 69 or 71, ie rotationally driven from the rotation of the mast 29. At least one of the driving devices connected to rotate the hub may be driven to rotate about the axis ZZ.

For the reasons described below, on the one hand between each driven disk 35 and 37 and on the other hand between the drive disk 33 and the mast 29, the relative rotation axis ZZ of the mast 29 is centered. In the portion surrounding the mast 29 in an axial direction between two radially annular bearings 89 which are substantially coaxial about the axis ZZ of the mast and surround the mast 29. Each driven disk 35 and 37 is mounted. Thus, the central portion of the driven disk 35 rests against the inner radial bearing 89 which rests against the shoulder 39 of the mast 29 and the inner axial end of the journal 47 of the drive disk 33. While the center portion of the other driven disk 37 is seated against the outer end face of the journal 49 of the drive disk 33, and the mast is fitted between the outer radial bearing 89. Three disks 33 35 and 37 by means of an axial preload device 41 schematically shown in the drawing, consisting of a nut 91 screwed around the male threaded portion 29b of (29). The stack of four bearings 89 is sandwiched between another radial bearing 89 which exerts a load in the axial direction, ie in the axial direction.

It may be simple but is preferably a radially annular bearing 89, which may each be a cylindrical laminated bearing as shown, or perhaps may be frustoconical and comprises at least one vulcanized elastomer washer between two metal washers. In addition, two axial bushings 93 are provided to facilitate relative rotation on the one hand between the respective driven disks 35 and 37 on the other and on the other mast 29 and the drive disk 33 on the other. . One of the two bushings 93 fits between the circumference 57 of the driven disk 35 and the journal 47 of the drive disk 33, while the other axial bushing 93 is another driven. It fits between the circumference 59 of the disk 37 and another journal 49 of the drive disk 33. These two axial bushings 93 are also substantially coaxial about the axis Z-Z of the mast 29.

2 to 6, the two drive pins 69 of the driven disk 35 not only oppose the axis ZZ oppositely, but also radially outward of the driven disk 35 on the axis ZZ. The differential mechanism 31 is configured to protrude perpendicularly with respect to and coaxially about the first diameter axis XX of the mechanism 31 and the mast 29, so that the pin 69 is connected with the driven disk 35. It constitutes an integral first diameter drive arm. Similarly, the two drive pins 71 of the driven disk 37 are also opposite to the axis ZZ and perpendicular to this axis ZZ and bounce radially outward of the driven disk 37. Protrudes and is coaxial about a second diameter axis YY of the mechanism 31 which is perpendicular to the first diameter axis XX in the stationary state and converges with a first diameter axis at a point on the axis ZZ. The drive pin 71 rotates integrally with the driven disk 37 and constitutes a second diameter drive arm perpendicular to the first diameter drive arm formed by the pin 69 when the mechanism 31 is at rest. do.

The differential mechanism 31 constitutes a drive means and a tilting means, in which the dual gimbal device 96 is arranged between the differential mechanism 31 on the one hand and the rotor hub support blade on the other hand, and thus the mast 29 Dual gimbal device as shown in FIGS. 7 and 8 for a rotor that intersects the axis ZZ and extends about any flapping axis extending in any direction about this axis ZZ. As compatible with 96, the hub and thus the rotor can be rotatably driven about a geometric axis inclined in any direction about the axis ZZ of the mast 29.

Referring now to FIGS. 7 and 8, the dual gimbal arrangement 96 can be a simple cylindrical bearing or preferably two first bearings 101a, which may be cylindrical, conical, and / or suitable spherical laminated elements. 101b) includes a first gimbal 97 of substantially octagonal (viewed in plan) shape mounted to pivot about mast 29. In addition, the second gimbal 99, which is substantially octagonal in shape and disposed above the first gimbal 97, is of the same type as the bearings 101a and 101b such that the second gimbal 99 is pivotable relative to the mast 29. It is mounted so as to be pivotable in a similar manner by two second bearings such as phosphor bearing 103a (the other bearing is invisible).

The two gimbals 97 and 99 are thus driven to rotate by respective driven disks 35 and 37 respectively, which are driven by the mast 29 and the drive disk 33 of the mast 29. While driven about an axis ZZ, each is pivotally mounted about two generally perpendicular axes XX and YY.

In addition, the first gimbal 97 is hingedly connected to the case or hub body by two first ball joint connections, such as 107a (see FIG. 8), wherein the ball joint connection is preferably a stacked ball joint. Each of which is combined with a cylindrical stacked bearing or a conical stacked bearing, opposite to the axis ZZ of the mast 29, each centered on the second diameter axis YY, the neutral of the rotor. Retained in two small sleeves 105 coaxial about the axis YY on the first gimbal 97 in position or at rest position, the first gimbal 97 about the first diameter axis XX When pivoted, two first ball joint connections, such as 107a , remain substantially central in the diameter plane formed by the axis ZZ and the second diameter axis YY.

In a similar manner, the second gimbal 99 is hingedly connected to the hub body by two second ball joint connections 109a and 109b, which ball joint connections are also preferably cylindrically stacked bearings or conical stacks. A laminated ball joint engaged with the static bearing, the opposite of which is opposed to the axis ZZ and located centrally at the stop of the rotor or at the neutral position of the rotor, respectively, while on the second gimbal 99 These ball joint connections 109a and 109b are held in axis ZZ when the second gimbal 99 is pivoted about a second diameter axis YY and is held in a compact sleeve 111 coaxial about (XX). And substantially centrally in the diameter plane formed by the first diameter axis XX.

In this embodiment, the rotor hub is connected to the mast 29 by two gimbals 97 and 99 and a predetermined mechanism that intersects the hinge, which is hinged inside the hub by a ball joint connection. Connected, preferably laminated, such as 107a and 109a and 109b and hingedly connected, by means of bearings 101a and 101b such as 103a , which at the same time constitute a mechanism for tilting the hub and blade Pivots about two vertical diameter drive arms 69-69 and 71-71 at an angle that intersects axis ZZ of the mast 29 as a whole and extends in any direction about axis ZZ Allows pivoting of the hub about the flapping axis, wherein the predetermined mechanism causes the gimbals 97 and 99 to pivot about their respective diameter axes XX and YY, thereby about the axis ZZ of the mast 29. random Around the geometrical axis of rotation of the hub which may be inclined in the direction provides a constant-velocity drive of the hub and blades. The torque is between the mast 29 and the hub, respectively, on the mast 29, the central disk 33, one driven disk 35 and 37, and thus the gimbal pivoting on the driven disk 35 or 37, respectively. 97 or 99), two corresponding bearings 101a, 101b, or a bearing such as 103b , two transmission trains comprising hubs and corresponding two ball joint connections, such as 107a or 109a , 109b .

With this type of pivoting device with two gimbals 97 and 99, the tilting of the rotor disk and thus the tilting of the hub relative to the axis ZZ of the mast 29 is 2Ω, where Ω is the rotation of the rotor. It is known that the two gimbals 97 and 99 cause periodic relative rotation of the two gimbals 97 and 99 at a rotational speed of the speed of the two gimbals 97 and 99. Relative motion with the same amplitude is performed. The differential mechanism 31 connects the driven disks 35 and 37 to the drive disk 33 and involves the rotation of the driven disks 35 and 37 in the opposite direction about the axis ZZ of the mast 29. Kinematically compensates for the aforementioned periodic relative rotation of the two gimbals 97 and 99 by means of a slightly inclined connecting pin 73. At the same time, the static torque transmitted by the mast 29 to the two gimbals 97 and 99 is distributed by means of the connecting pin 73 by the drive disk 33 between the two driven disks 35 and 37. do. This ability of the differential mechanism 31 to allow any relative movement of the two gimbals 97 and 99 in a plane perpendicular to the drive shaft is such that a tilting mechanism with two gimbals is directly connected to the mast 29. It eliminates the hyperstatic nature of the device.

The constant velocity characteristic is thus obtained using the differential mechanism 31 by the kinematic compatibility between the drive means and the tilting means using the two gimbals 97 and 99.

The loads (lift and coplanar loads) from the rotor to the mast 29 are transferred from the hub to the mast 29 via two gimbals 97 and 99 that transfer torque in opposite directions from the mast 29 to the hub. Delivered. Radial annular bearings 89 and axial bushings that enable relative rotation between the drive disk 33 and the driven disks 35 and 37 (connected to gimbals 97 and 99) connected to the mast 29. 93 aids in the transfer of lift loads and coplanar loads, the lift also being associated with three disks 33, 35 and 37 and four radial annular bearings 89 for the shoulder 39 on the mast 29. Is transmitted through the presence of the axial preload device 41 when it is elastically deformed.

The constant speed drive system taught by Chopitelli et al. May be suitable for smaller, lighter and less powerful rotorcraft, while the constant speed drive system taught by Choritelli et al. For use in larger, heavier and more powerful rotorcraft. It is apparent that there are significant limitations when considering this. For example, to increase the torque transmission capability of a constant velocity drive system taught by Chopitelli et al., It is necessary to increase the overall size of the torque distribution mechanism. In addition, since the two gimbal devices associated with the torque distribution mechanism substantially surround the torque distribution mechanism, there is a need to also increase the overall size of the two gimbal devices. Rotating elements of the rotor system are preferably configured to be kept as close as possible to the axis of rotation of the mast in order to minimize undesirable final forces. Clearly, increasing the size of the two gimbal devices and torque distribution mechanisms taught by Chopitelli et al. Is undesirable and does not provide a satisfactory solution for providing a constant velocity drive system for larger, heavier and more powerful rotorcraft. can not do it.

The improvement of the rotor hub described above represents a significant advance in the rotor hub configuration but significant disadvantages remain.

There is a need for an improved constant speed drive system that can deliver greater torque while minimizing negative dynamic effects and meeting component sizing / package requirements.

It is therefore an object of the present invention to provide an improved constant speed drive system that can deliver greater torque while minimizing negative dynamic effects and meeting component sizing / package requirements.

This object is achieved by providing a constant velocity drive system comprising a torque distribution mechanism substantially displaced along the axis of rotation from a plurality of drive links and / or associated gimbal mechanisms. The constant speed drive system has (1) torque distributing mechanism transmitting force to the gimbal mechanism (located farther from the rotorcraft fuselage than the torque distributing mechanism) and the gimbal mechanism transmitting force to the rotor hub, or (2) torque distributing mechanism The gimbal mechanism (which is located closer to the rotorcraft aircraft body than the torque distribution mechanism) transmits force and the gimbal mechanism can be configured to transmit force to the rotor hub.

The present invention provides (1) an improved constant velocity drive system with reduced negative dynamic effects on rotorcraft, (2) greater torque transfer through a differential torque distribution mechanism, and (3) differential torque When the dispensing mechanism is axially spaced apart from the dual gimbal mechanism, it provides significant advantages, including providing a robust structural connection for connecting the differential torque dispensing mechanism and the dual gimbal mechanism.

Additional objects, features and advantages will be apparent from the description which follows.

New features that are believed to be features of the invention are set forth in the appended claims. However, the preferred mode of use and further objects and advantages of the present invention as well as the present invention will be best understood by reading with reference to the following detailed description in conjunction with the accompanying drawings.

1 is a side view of a tilt rotor aircraft of the prior art having a constant speed drive system as taught by Chopitelli et al.

2 is a plan view of a differential mechanism of the constant velocity drive system of FIG.

3 is a cross-sectional view of the differential mechanism of FIG. 2 taken at cut line 3-3 of FIG.

4 is a cross-sectional view of the differential mechanism of FIG. 2 generally taken at cut line 4-4 of FIG. 2.

5 is an exploded perspective view of the differential mechanism of FIG. 2.

6 is a perspective view of the differential mechanism of FIG. 2.

7 is an exploded perspective view of the dual gimbal device and differential mechanism of the constant velocity drive system of FIG.

8 is a perspective view of a dual gimbal arrangement and differential mechanism of the constant velocity drive system of FIG.

9 is a front view of a tilt rotor rotorcraft having a constant velocity drive system according to the present invention.

10 is a schematic diagram of a constant speed drive system according to the present invention.

11 is a schematic view of a variant of the constant speed drive system according to the invention.

12 is a side view of a preferred embodiment of the constant speed drive system according to the present invention.

FIG. 13 is a side view of a differential torque distribution mechanism of the constant velocity drive system of FIG. 12.

FIG. 14 is a top view of the dual gimbal mechanism of the constant velocity drive system of FIG. 12.

FIG. 15 is a plan view of a differential torque distribution mechanism of the constant velocity drive system of FIG. 12.

FIG. 16 is a simplified schematic cross-sectional view (section taken at cut line D-D in FIG. 15) of the differential torque distribution mechanism of the constant velocity drive system of FIG.

FIG. 17 is a simplified schematic cross-sectional view (sectional view taken on cut line C-C in FIG. 15) of the differential torque distribution mechanism of the constant velocity drive system of FIG. 12.

18 is a perspective view of a modification of the triple joint pin in a modification of the differential torque distribution mechanism according to the present invention.

19 is a perspective view of a variant of the constant speed drive system according to the invention.

The present invention relates to a constant velocity drive system improved for a rotorcraft aircraft, the constant velocity drive system having improved torque transmission while minimizing negative dynamic characteristics. Reference is specifically made to the use of the present invention with a tilt rotor rotorcraft, but the present invention may alternatively be used with any other rotorcraft vehicle / airplane.

9 shows a tilt rotor rotorcraft including the constant velocity drive system of the present invention. 9 shows the tilt rotor aircraft 201 in airplane mode during flight operation. When in airplane mode, the wing 203 is used to float the aircraft fuselage 205 in response to the operation of the rotor systems 207 and 209. Each rotor system 207, 209 is shown having four rotor blades 211. Each nacelle 213, 215 substantially surrounds a constant velocity drive system 217 (along the associated rotary cover 216), thereby rendering the constant velocity drive system 217 invisible in FIG. 9. Of course, each rotor system 207, 209 is driven by an engine (not shown), each engine being substantially housed in one of the nacelle 213, 215.

Referring now to FIG. 10 in the drawings, a simplified schematic diagram of a constant speed drive system 217 according to the present invention is shown. The constant speed drive system 217 is adapted to operate in a substantially similar manner as a constant speed drive system such as Chopitelli. The constant speed drive system 217 generally comprises a differential torque distribution mechanism 219, a gimbal mechanism 221 and at least two link means 223, 225. The differential torque distribution mechanism 219 and the gimbal mechanism 221 are associated with a rotor mast 227 that is configured to rotate about the central axis of rotation R-R of the mast 227. The mast 227 includes an aircraft inner portion 229 and an aircraft outer portion 231. The aircraft inner portion 229 is located closer to the engine and / or transmission link than the aircraft outer portion 231 when assembled for operation and thus connected to the transmission link and / or engine between the engine and the mast 227. do. The differential torque distribution mechanism 219 is located closer to the aircraft inner portion 229 than the gimbal mechanism 221, while the gimbal mechanism 221 is closer to the aircraft outer portion 231 than the differential torque distribution mechanism 219. It is located close by.

In general, the differential mechanism 219 provides substantially the same function as the differential torque distribution mechanism 31 as taught by Chopitelli et al., And the gimbal mechanism 221 is also a dual gimbal as taught by Chofitelli et al. It provides substantially the same functionality as device 96. The differential mechanism 219 and the gimbal mechanism 221 are substantially displaced from each other along the mast 227, and link means 223, 225 are used to connect the differential mechanism 219 and the gimbal mechanism 221. . The link means 223, 225 complement and complement the differential torque distribution mechanism 219 and the gimbal mechanism 221 in such a way that each link means 223, 225 is part of at least two independent force transmission paths. And a periodic counterpart by the gimbal mechanism 221 when the link means 223, 225 join together in transmitting static torque from the differential mechanism 219 to the gimbal mechanism 221. Rotation allows the differential mechanism 219 to kinematically compensate. This ability of the differential mechanism 219 to allow at least two portions (not shown) of the gimbal mechanism 221 to randomly move in a plane perpendicular to the axis RR is such that a two gimbal tilting mechanism connects directly to the mast. This eliminates the hyperstatic nature of the device. Gimbal mechanism 221 is attached to a rotor hub (not shown) for rotationally driving the rotor hub when further assembled for operation.

Referring now to FIG. 11 in the drawings, a simplified schematic diagram of a constant velocity drive system according to the present invention is shown. The constant speed drive system 233 is functionally similar to the constant speed drive system 217. However, the constant speed drive system 233 has a differential torque distribution mechanism 219 located closer to the aircraft outer portion 231 than the gimbal mechanism 221 while the gimbal mechanism 221 is more than the differential torque distribution mechanism 219. It is different from the constant velocity drive system 217 in that it is located closer to the aircraft inner portion 229.

The constant speed drive system 217 and the constant speed drive system 233 are different, but each constant speed drive system 217, 233 radially (with respect to the axis of rotation of the mast) the physical size of the differential torque distribution mechanism or gimbal mechanism. The constant speed drive systems 217 and 233 are an improvement over the constant speed drive system 27 such as Chopitelli, as long as it provides a desirable constant speed drive system that can deliver larger torque loads without expanding. This is generally achieved by displacing the differential torque distribution mechanism (along the rotation axis R-R of the mast) from the gimbal mechanism. By displacing the differential torque mechanism from the gimbal mechanism, the input of the constant speed drive system (which transfers torque from the mast to the differential torque mechanism) is moved from the output of the constant speed drive system (which transfers torque from the gimbal mechanism to the associated rotor hub). Along the axis of rotation).

Referring now to FIGS. 12-17 of the drawings, there is shown a constant speed drive system 301 according to a preferred embodiment of the present invention. The constant speed drive system 301 also has a dual gimbal mechanism 305 (shown in FIGS. 12 and 14) and a differential torque distribution mechanism 303 that function together to provide benefits by the constant speed drive system 217. ) (Shown in greater detail in FIGS. 13 and 15-17). The differential torque distribution mechanism 303 includes a central drive disk 307 which is integral with the mast 309 to rotate about the axis of rotation S-S. The differential torque distribution mechanism also includes an inner driven tube 311 and an outer driven tube 313. The inner driven tube 311 includes a base 315, a riser portion 317 and a drive arm portion 319. Similarly, the outer driven tube 313 includes a base 321, a riser portion 323 and a drive arm portion 325.

Substantially, the bases 315 and 321 have a disk shape that is generally located perpendicular to the axis of rotation S-S. The inner driven tube 311 and the outer driven tube 313 are located concentrically about the rotation axis S-S, and the inner driven tube 311 is located between the outer driven tube 313 and the mast 309. As shown more clearly in FIGS. 15 and 16 [FIG. 16 is a schematic cross-sectional view taken at the axis / cut line DD of FIG. 15, and FIG. 17 is taken at the axis / cut line CC of FIG. 15. Schematic cross-sectional view, the bases 315 and 321 work with the central drive disk 307 by using a triple joint pin 327. Thus, the triple joint pin 327 allows relative rotation about the axis of rotation S-S of the mast 309 between each inner driven tube 311 and outer driven tube 313. The triple joint pins 327 each comprise three ball joints, namely a center joint and two end joints (not shown for clarity), and for each triple joint pin 327 Associated with the central drive disk 307, the two remaining end joints are associated with the bases 315, 321. In this embodiment the inner base 315 is located above the central drive disk 307 and the outer base 321 is located below the central drive disk 307. Of course, other necessary bearings, axial preload devices, bushings and / or interface components are integrated into the differential torque distribution mechanism 303 as needed, such integration being known to those skilled in the art and applicable to this embodiment in view of the present teachings. Can be.

Substantially, riser portions 317 and 323 have the shape of a tube extending from bases 315 and 321 along axis of rotation S-S, respectively. The riser portions 317, 323 function substantially the same as the link means 223, 225 of FIGS. 10 and 11, to transfer torque from the base 315, 321 to the drive arm portions 319, 325, respectively. It is composed. The riser portions 317, 323 are such that they are practicable on the axis SS while maintaining any necessary space between the mast 309 and the riser portion 317 and between the riser portion 317 and the riser portion 323. The size and shape are determined to be generally in close proximity.

Drive arm portions 319 and 325 generally comprise cylindrical protrusions that resemble pins extending from riser portions 317 and 323, respectively, and extending radially away from axis of rotation S-S. Drive arm portions 319 and 325 generally act as interfaces between inner driven tube 311 and outer driven tube 313 and dual gimbal device 305 respectively. As most clearly shown in FIG. 15, drive arm portion 325 is located along axis CC while drive arm portion 319 is located along axis DD, which axes are generally perpendicular to one another. All are generally perpendicular to the axis of rotation SS.

As shown in FIG. 14, the dual gimbal mechanism 305 includes a first gimbal 329 and a second gimbal 331. The first gimbal 329 includes a gimbal arm 333 and a gimbal joint 335, while the second gimbal 331 includes a gimbal arm 337 and a gimbal joint 339. The dual gimbal device 305 is connected to the inside of the rotor hub (not shown) through a ball joint (not shown) integrated into four gimbal joints 335 and 339 radially located outermost from the axis SS. It is. In a manner substantially similar to the dual gimbal device 96 of FIGS. 7 and 8, the dual gimbal mechanism 305 constitutes a mechanism for tilting the rotor hub and attached blades, intersecting the axis SS and crossing the shaft ( Mechanisms that allow the hub to pivot as a whole about any flapping axis extending in any direction about SS) and enable constant speed drive of the rotor hub and blades about the axis of rotation of the rotor hub The mechanism can be tilted in any direction about axis SS by having gimbals 329 and 331 pivot about their respective axes DD and CC.

The drive arm portion 319 is flexibly connected to the second gimbal 331 and is adapted to drive the second gimbal. Specifically, drive arm portion 319 is connected to gimbal joint 339 'along axis D-D. Similarly, drive arm portion 325 is flexibly connected to first gimbal 229 and is adapted to drive the first gimbal. Specifically, drive arm portion 325 is connected to gimbal joint 325 ′ located along axis C-C. As clearly shown in FIG. 13, since the inner driven tube 311 is located concentrically within the outer driven tube 313, an appropriately sized cut 341 is located on the riser portion 323 to provide a double Allow drive arm portion 319 to pass through for connection with gimbal mechanism 305.

Referring now to FIG. 18, a variant of a portion of a triple joint pin according to the present invention is shown. The triple joint pin 327 is shown to include three ball joint portions, but the triple joint action of the drive pins even when replacing one of the three joints with a joint of a type other than the ball joint. It will be appreciated that it may be maintained. Specifically, the triple joint pin 401 includes a central cylindrical joint portion 403 and two end ball joint portions 405. The cylindrical joint portion 403 is disposed coaxially with the axis Q-Q. The ball joint portion 405 is arranged to be centered and displaced along the axis P-P. Axis Q-Q and axis P-P are substantially perpendicular. It is preferable to orient the triple joint pin 401 such that the axis Q-Q extends substantially radially from the rotation axis S-S. The triple joint pin 401 provides a similar interaction as the triple joint pin 327 between the central drive disk, the inner driven tube and the outer driven tube, but the triple joint pin 401 is along the axis QQ. Improve the ability to translate and rotate around the axis (QQ). Of course, additional and / or different bearing structures required to form the center drive disk, the inner driven tube and the outer driven tube and the interface of the triple joint pin 401 are known to those skilled in the art, and the present embodiment in view of the present teachings. Can be applied to

Referring now to FIG. 19, a constant velocity drive system according to the present invention is shown. The constant speed drive system 501 generally includes a differential torque distribution mechanism 503, a dual gimbal device 505, and a drive arm 507 for transmitting torque from the differential torque distribution mechanism 503 to the dual gimbal device 505. ). The differential torque distribution mechanism 503 is substantially similar in shape and function to the differential mechanism 31 but is adapted to be connected to the drive arm 507 rather than directly to the dual gimbal device 505. In addition, the dual gimbal device 505 is substantially similar to the dual gimbal device 96 but the dual gimbal device 505 does not substantially obscure the differential torque distribution mechanism 503, but rather away from the differential torque distribution mechanism 503. Direction is substantially displaced along the axis WW (rotational axis of the mast 511). Whereas the drive arm 507 is a member of an irregularly curved shape, variants of the drive arm can be shaped and sized in various ways, while still delivering adequate torque without undesirably deforming the drive arm. Done. Specifically, the drive arm 507 is adapted to be connected at one end to the drive pin 509 of the differential torque distribution mechanism 503 and at the other end to the drive joint 513 of the dual gimbal device 505. In general, the torque transmission path of the constant speed drive system 501 is substantially similar to the torque transmission path of the constant speed drive system 27, but between the axially displaced differential torque distribution mechanism 503 and the dual gimbal device 505. Torque is additionally transmitted through the drive arm 507 to allow connection of the.

It is clear that the invention described and illustrated has significant advantages. While the invention has been shown in a finite number of forms, the invention is not limited to only these forms and can be modified in various changes and modifications without departing from the spirit of the invention.

Claims (20)

A rotor mast that can be driven to rotate about a longitudinal axis, In such a way that the hub can be driven to rotate at constant speed about the geometric axis of rotation of the hub which can be tilted in any direction about the longitudinal axis of the mast, perpendicular to the axis of the mast and to the axis of the mast. A hub connected to the mast by a constant velocity drive mechanism and a tilting device allowing the hub to pivot entirely about any converging flapping axis, At least two blades each connected to the hub by couplings that hold the blades at a predetermined pitch and are hingedly connected; Wherein the constant velocity drive mechanism comprises a differential mechanism for distributing static torque in a plane perpendicular to the axis of the mast and allowing relative movement between at least two devices for driving the hub, wherein the differential mechanism includes: The disk set comprising three disks that are substantially stacked and are substantially coaxial about the axis of the mast, the disk being disposed between the second and third disks of the disk set along the axis of the mast The first disk of the set is a drive disk, each of the three ball joint connections having an integral longitudinal rotation with the mast and having a geometric longitudinal axis substantially parallel to the axis of the mast and substantially centered on the geometric longitudinal axis. Hinge to each disk in the disk set by Of the at least two drive devices, each of which is connected to each of the second and third disks, which are driven disks, by means of at least one connecting pin connected to each other; A constant velocity connected to the hub by at least one to rotationally drive the hub about the geometric axis of rotation of the hub, wherein the at least two drives are substantially separated from the differential mechanism along the axis of the mast by a predetermined distance Rotorcraft aircraft with drive. A convertible aircraft comprising at least one tilt rotor that is movable from a first position in which the tilt rotor or each tilt rotor acts as an airplane propeller to a second position in which the tilt rotor or each tilt rotor acts as a helicopter main lifting rotor. The tilt rotor or each tilt rotor includes a rotor mast that can be driven rotationally about a longitudinal axis and a constant velocity of the hub by the mast about a geometric axis of rotation of the hub that can be tilted in any direction about the axis of the mast. A hub connected to the mast by a constant velocity drive mechanism and a tilting device that allows the hub to pivot entirely about any flapping axis perpendicular to the axis of the mast and converging to the axis of the mast, in a manner that can be driven to rotate. And at least two blades each connected to the hub by couplings that hold the blades at a predetermined pitch and hingeably connect the blades, The constant velocity drive mechanism includes a differential mechanism for distributing static torque in a plane perpendicular to the axis of the mast and allowing relative movement between at least two devices for driving the hub, the differential mechanism being substantially stacked A disk set of three disks arranged in a manner and substantially coaxial about the axis of the mast, the first set of disks being disposed between the second and third disks of the disk set along the axis of the mast The disk is a drive disk, integral with the mast to rotate with the disk by each of three ball joint connections having a geometric longitudinal axis substantially parallel to the axis of the mast and being substantially centered on the geometric longitudinal axis. Enemy hinged to each disk in the set It is connected to each of the second and third disks, which are driven disks by at least one connecting pin, wherein the second and third disks are also connected to at least one of the at least two drive units, each hingedly connected to the hub. Coupled to the hub to rotationally drive the hub about the geometric axis of rotation of the hub, wherein the at least two drive units are substantially separated from the differential mechanism along the axis of the mast by a predetermined distance. A differential torque distribution mechanism adapted to interface with a mast about a longitudinal mast axis of rotation, the drive disk being coaxial with the mast axis of rotation and being rotatably integrated with the mast, An inner base coaxial with the mast axis and adjacent to the drive disc, an inner riser portion coaxial with the mast axis and extending away from the inner base, and substantially radially extending from the inner riser portion and a considerable distance along the mast axis away from the inner base. An inner driven member including a spaced inner drive arm, An outer base coaxial with the mast axis and adjacent to the drive disk, an outer riser portion coaxial with the mast axis and extending from the outer base toward the inner drive arm, and generally radially extending from the outer riser portion and along the mast axis away from the outer base. An outer driven member including an outer drive arm spaced apart by a predetermined distance, A differential torque distribution mechanism comprising a triple joint pin each having three joint connections pivotally engaged with the drive disk, the inner base, or the outer base, and Gimbal mechanism is configured to be driven rotatably by the inner drive arm and the outer drive arm and is connected to the rotor hub so that the rotor hub can be gimbally connected to the mast. Constant speed drive system for a rotorcraft rotor rotor comprising a. 4. The system of claim 3, wherein at least one of the triple joint pins also includes an opposing end ball joint, and a central cylindrical joint having a central cylindrical joint axis, the central cylindrical joint pivotally engaging the drive disk, Wherein the central cylindrical joint axis is substantially radial relative to the mast axis and the at least one pivot pin is configured to translate along the central cylindrical joint axis. 4. The constant velocity drive system of claim 3, wherein at least one of the triple joint pins also includes at least one elongated joint having a longitudinal axis disposed generally radially relative to the mast axis. A drive disk adapted to be rotatably integrated with the mast, an upper member at least partially positioned on the driven disk, a lower member at least partially positioned below the driven disk, and connecting the upper member and the lower member to the drive disk. A differential mechanism comprising at least one link, wherein the drive disk drives the upper member and the lower member to rotate with the drive disk and the upper member and the lower member are allowed to rotate differently relative to the drive disk; A gimbal device for driving the rotor hub and allowing the gimbal of the rotor hub to the mast and a predetermined distance from the differential mechanism along the length of the mast, Wherein the upper member and the lower member are adapted to rotationally drive the gimbal device. 7. The constant velocity drive system of claim 6, wherein the upper member and the lower member each comprise a tubular portion, the tubular portion being concentric. 7. The gimbal device of claim 6, wherein the gimbal device comprises a first drive path portion and a second drive path portion, wherein the upper member is attached to the first drive path portion and the lower member is attached to the second drive path portion. Constant velocity drive system for rotary rotorcraft rotors. 7. The apparatus of claim 6, wherein the at least one link comprises opposing end joints and a central joint, the central joint pivotally engaging the drive disc and each end joint pivoting with one of the upper and lower members. Constant speed drive system for a rotorcraft rotor rotor that is possibly interlocked. 10. The constant velocity drive system of claim 9, wherein the opposing end joints and the central joint are each ball joints. 10. The method of claim 9, wherein the opposing end joints are each a ball joint and the central joint is a generally cylindrical joint with a central cylindrical joint axis, the central cylindrical joint axis is substantially radial relative to the mast and the at least one link is A constant velocity drive system for a rotorcraft rotor rotor configured to translate along a central cylindrical joint axis. 7. The constant velocity drive system of claim 6, wherein the link comprises at least one elongated joint, the longitudinal axis of the elongate joint being disposed substantially radially relative to the mast. A rotor mast that can be driven to rotate about a longitudinal axis, Converging to the axis of the mast and perpendicular to the axis of the mast in such a way that the hub can be driven to rotate at constant speed about the geometric axis of rotation of the hub which can be tilted in any direction about the axis of the mast. A hub connected to the mast by a constant velocity drive mechanism and a tilting device allowing the hub to pivot entirely about any flapping axis; At least two blades each connected to the hub by couplings that hold the blades at a predetermined pitch and are hingedly connected; Wherein the constant velocity drive mechanism comprises a differential mechanism for distributing static torque in a plane perpendicular to the axis of the mast and allowing relative movement between at least two devices for driving the hub, wherein the differential mechanism includes: The disk set comprising three disks arranged substantially stacked and substantially coaxial about the axis of the mast, the disk set being disposed between the second and third disks of the disk set along the axis of the mast The first disk of is a drive disk, two opposing ball joints integrally rotating with the mast, each having a geometric longitudinal axis substantially parallel to the axis of the mast and each being substantially centered on the geometric longitudinal axis. By means of a connection and a central cylindrical joint connection respectively Connected to each of the second and third disks, which are driven disks, by at least one connecting pin hingedly connected to each disk in the disk set, the second and third disks also being hinged to the hub, respectively. A rotorcraft rotor with a constant velocity drive connected to the hub by at least one of the at least two drive devices connected to each other to rotate the hub about the geometric axis of rotation of the hub. 14. The rotorcraft rotor of claim 13, wherein the at least two drive units are separated substantially from the differential mechanism along the axis of the mast by a predetermined distance. A convertible aircraft comprising at least one tilt rotor that is movable from a first position in which the tilt rotor or each tilt rotor acts as an airplane propeller to a second position in which the tilt rotor or each tilt rotor acts as a helicopter main lifting rotor. The tilt rotor or each tilt rotor, A rotor mast that can be driven to rotate about the longitudinal axis of the mast, Converging to the axis of the mast and perpendicular to the axis of the mast in such a way that the hub can be driven to rotate at constant speed about the geometric axis of rotation of the hub which can be tilted in any direction about the axis of the mast. A hub connected to the mast by a constant velocity drive mechanism and a tilting device allowing the hub to pivot entirely about any flapping axis; At least two blades each connected to the hub by couplings that hold the blades at a predetermined pitch and are hingedly connected; Wherein the constant velocity drive mechanism comprises a differential mechanism for distributing static torque in a plane perpendicular to the axis of the mast and allowing relative movement between at least two devices for driving the hub, wherein the differential mechanism includes: The disk set comprising three disks arranged substantially stacked and substantially coaxial about the axis of the mast, the disk set being disposed between the second and third disks of the disk set along the axis of the mast The first disk of is a drive disk, two opposing ball joints integrally rotating with the mast, each having a geometric longitudinal axis substantially parallel to the axis of the mast and each being substantially centered on the geometric longitudinal axis. By means of a connection and a central cylindrical joint connection respectively Connected to each of the second and third disks, which are driven disks, by at least one connecting pin hinged to each disk in the set, the second and third disks are also hinged to the hub, respectively. A diverted aircraft, which is connected to the hub by at least one of the at least two drive devices connected to rotate the hub about the geometric axis of rotation of the hub. 16. The diverted aircraft of claim 15 wherein the at least two drive devices are separated substantially from the differential mechanism along the axis of the mast by a predetermined distance. A rotor mast that can be driven to rotate about the longitudinal axis of the rotor mast, Converging to the axis of the mast and perpendicular to the axis of the mast in such a way that the hub can be driven to rotate at constant speed about the geometric axis of rotation of the hub which can be tilted in any direction about the axis of the mast. A hub connected to the mast by a constant velocity drive mechanism and a tilting device allowing the hub to pivot entirely about any flapping axis; At least two blades each connected to the hub by couplings that hold the blades at a predetermined pitch and are hingedly connected; Wherein the constant velocity drive mechanism comprises a differential mechanism for distributing static torque in a plane perpendicular to the axis of the mast and allowing relative movement between at least two devices for driving the hub, wherein the differential mechanism includes: The disk set comprising three disks arranged substantially stacked and substantially coaxial about the axis of the mast, the disk set being disposed between the second and third disks of the disk set along the axis of the mast The first and second disks of the second and third disks are integral to rotate with the mast and have a geometric longitudinal axis substantially parallel to the axis of the mast and are driven disks by at least one connecting pin. Connected to each of the disks, the second disk and the third disk each being Connected to the hub by at least one of the at least two drive devices connected in a manner to rotationally drive the hub about the geometric axis of rotation of the hub, the connecting pin being on the geometric longitudinal axis of the connecting pin. A rotorcraft rotor rotor with a constant velocity drive wherein essentially no centered three ball joint connections are required components. 18. The rotorcraft of claim 17, wherein the at least two drive units are substantially separated from the differential mechanism along the axis of the mast by a predetermined distance. A convertible aircraft comprising at least one tilt rotor that is movable from a first position in which the tilt rotor or each tilt rotor acts as an airplane propeller to a second position in which the tilt rotor or each tilt rotor acts as a helicopter main lifting rotor. A rotor mast that can be driven to rotate about the longitudinal axis of the rotor mast, Converging to the axis of the mast and perpendicular to the axis of the mast in such a way that the hub can be driven to rotate at constant speed about the geometric axis of rotation of the hub which can be tilted in any direction about the axis of the mast. A hub connected to the mast by a constant velocity drive mechanism and a tilting device allowing the hub to pivot entirely about any flapping axis; At least two blades each connected to the hub by couplings that hold the blades at a predetermined pitch and are hingedly connected; Wherein the constant velocity drive mechanism comprises a differential mechanism for dividing static torque in a plane perpendicular to the axis of the mast and allowing relative movement between at least two devices for driving the hub, wherein the differential mechanism includes: The disk set comprising three disks arranged substantially stacked and substantially coaxial about the axis of the mast, the disk set being disposed between the second and third disks of the disk set along the axis of the mast The first and second disks are drive disks, the second disk and the third being driven disks by at least one connecting pin having a geometric longitudinal axis substantially parallel to the axis of the mast and integral with the mast to rotate. Are connected to each of the disks, and the second and third disks are each Connected to the hub by at least one of the at least two drive devices connected in a manner to rotate the hub about the geometric axis of rotation of the hub, the connecting pin being substantially on the geometric longitudinal axis of the connecting pin. A switchable aircraft in which the three ball joint connections at the center thereof are not required components. 20. The diverted aircraft of claim 19 wherein the at least two drive devices are substantially distanced from the differential mechanism along the axis of the mast by a predetermined distance.

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