A drive system for contrarotating motors for an aircraft

Abstract

A drive system for driving contrarotating motors includes a shaft. A first motor is mounted to the shaft. The first motor having a stator fixedly mounted to the shaft. The motor having a motor housing rotatably mounted on the stator. At least two rotor blades mounted to the motor housing. The motor housing rotating in a first direction when energized by a battery. A second motor is mounted to the shaft coaxially with the first motor. The second motor has a second stator fixedly mounted to the shaft. The second motor having a second motor housing rotatably mounted on the stator. A third rotor blade and fourth motor blade are mounted to the second motor housing. The second motor housing rotating in a second direction; an opposite direction to the first direction.

Description

A DRIVE SYSTEM FOR CONTRAROTATING MOTORS FOR AN AIRCRAFTCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 518,200 filed on August 8, 2023. The entire contents of this application are incorporated herein by reference in its entirety.BACKGROUND OF THE INVENTION

[0002] The present invention is directed to a motor and propeller structure for an aircraft, particularly a helicopter, and more specifically coaxial contrarotating electric hub motors for use with a helicopter.

[0003] Helicopter motors for driving a single rotor, having a single propeller pair are known in the art. They usually comprise a single motor for driving two or more relatively co planar blades coupled to the motor. Single rotor helicopters have been satisfactory, but they suffer from the disadvantage that a single rotor helicopter requires a tail rotor to prevent rotation of the fuselage relative to the propeller shaft, which robs the power plant generally of about fifteen percent of its total power. Additionally, the tail rotor is susceptible to problems mechanically and aerodynamically as well. A single rotor also has a “fertilizer spreader effect” where the column of air moving downward spirals outward; reducing lift power.

[0004] Contrarotating propellers are known in the art and eliminate the need for use of a sideways thrusting tail. However, contrarotating blade systems are complicated mechanical systems requiring a gear box to split engine power at the shaft in order to simultaneously drive one coupled rotor clockwise and drive the other rotor counterclockwise, by separating the power into two directions. Additionally it is required that the rotors be driven about the same axis, the blade control system being mounted about the exterior of the rotor mast.

[0005] Accordingly, a structure and methodology making use of the contrarotating blades, to overcome the shortcomings of the prior art is provided.SUMMARY OF THE INVENTION

[0006] A drive system for driving contra rotating motors includes a shaft. A first motor is mounted to the shaft. The first motor having a stator mounted to the shaft, so as not to rotate relative thereto. The stator being a coil set. The motor having a motor housing rotatably mounted on the stator; the motor housing rotating about the stator. A first rotor blade mounted to the motor housing. A second rotor blade mounted to the motor housing. The motor housing rotating in a first direction when the coil set is energized by a battery. A second motor is mounted to the shaft coaxially with the first motor. The second motor having a second stator fixedly mounted to the shaft. The second stator being a coil set. The second motor having a second motor housing rotatably mounted on the shaft. A third rotor blade mounted to the second motor housing. A fourth rotor blade mounted to the second motor housing. The second motor housing rotating in a second direction when the coil set is energized by a battery; the second direction being opposite to the first direction.

[0007] A non-rotating swash plate mounted to the shaft. A rotating swash plate, acting as a cyclical bearing, is rotatably disposed about the non-rotating swash plate. A linkage assembly, disposed within the shaft, operatively coupled to the non-rotating swash plate changes the orientation of the non-rotating swash plate relative to the shaft causing the rotating swash plate to change orientation relative to the shaft. A driver assembly couples the rotatable swash plate to one of the first motor housing and second motor housing for matching the rotations of the housing, and in turn the blades.

[0008] In a preferred embodiment a leading edge of the first rotor blade is orientated in an opposite direction than a leading edge of the third rotor blade. The stator is slidably mounted to the shaft. The motor housings are rotatable mounted on the stator via bearings.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present disclosure will be better understood by reading the written description with reference to the accompanying drawing figures in which like reference numerals denote similar structure and refer to like elements throughout in which:

[0010] Fig. 1 an exterior perspective view of a drive system for contrarotating motors in accordance with the invention;

[0011] Fig. 2 is an exploded view of a motor assembly constructed in accordance with invention;

[0012] Fig. 3 is a perspective view of a driver assembly constructed in accordance with the invention;

[0013] Fig. 4 is a perspective view of a control rod assembly constructed in accordance with the invention in accordance with the invention;

[0014] Fig. 5 is perspective view of a swash plate constructed in accordance with the invention;

[0015] Fig. 6 is a side plan view of a drive system a drive system for contrarotating motors in accordance with the invention;

[0016] Fig. 7 is a side plan view of a linkage assembly for controlling each motor in accordance with the invention;

[0017] Fig. 8 is a side plan view of a linkage assembly for controlling each motor in accordance with the invention rotated ninety degrees from the view of Fig. 7; and

[0018] Fig. 9 is a perspective view of the linkage assembly in accordance with the invention..DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Reference is first made to FIG. 1 in which a contrarotating propeller motor, generally indicated as 100, is shown. Contrarotating propeller motor 100 includes a shaft 110, fixedly mounted to a vehicle body, not shown, but preferably a helicopter body. A first motor assembly 200 is affixed to an exterior of shaft 110 at a first position, and a second motor assembly 300 affixed to an exterior of shaft 110 at a position spaced from first motor 200. Motor assembly 200 rotates about the shaft in a direction opposite to that of motor assembly 300.

[0020] The structure of motor assembly 200 and the structure of motor assembly 300 are almost identical with the exception of the orientation of the blades thereof. Therefore, for ease of description, the inner structure of motor assembly 200 will be described as representative of both.

[0021] Reference is now also made to Figs. 1 and 2 in which the structure for a motor, generally indicated as 200 is provided. Motor 200 includes a motor housing bottom 204 having a magnet set cylindrical wall 214 extending therefrom. Magnet set cylindrical wall 214 are, in a nonlimiting preferred embodiment, a plurality of magnets. A hole 212 is disposed within bottom 204 for receiving shaft 1 10. A stator 206, formed, in a non-limiting preferred embodiment, as a coil set is disposed within wall 214 and has a hole 210 therein for receiving shaft 110. Similarly, stator 206 may be formed as a plurality of magnets and magnet set wall 214 as a plurality of coils. A motor housing top 202 has a hole 208 for receiving shaft 110 there through. When motor housing top 202 is affixed to housing bottom 204 to form housing 200, housing top 202 rests on wall 214, stator 206 is disposed within housing 200, and wall 214, separates housing top 202 from housing bottom 204, with holes 208, 210 and212 being concentric for receiving shaft 1 10 therethrough. The resulting housing 200 may be slidably mounted to shaft 110, but does not permit rotation of shaft 110. Housing bottom 204 and housing top 202 rotate about stator 206, when the stator magnet is energized.

[0022] It should be noted that in a preferred non limiting embodiment, each of housing top 202 and housing bottom 204 are formed with a plurality of holes about the circumference. These provide a plurality of attachment points for other structure such as propellers and driver assemblies, discussed below, about any number of positions about the motor.

[0023] As seen from Fig. 1 a first propeller assembly 230a includes a first rotor attachment 236a fixedly secured between housing top 202 and housing bottom 204. A first propeller 232a is secured to rotor attachment 236a by a rotor mount 234a. Similarly, a second propeller assembly 230b includes a second rotor attachment 236b fixedly secured between housing top 202 and housing bottom 204. A second propeller 232b is secured to rotor attachment 236b by a rotor mount 234b.

[0024] A cyclic bearing 240a is disposed along shaft, preferably at a position below housing 200. As seen in Fig 5, cyclic bearing 240a includes a fixed swash plate 218, and a rotating swash plate 216, rotatable disposed about fixed swash plate 218, which in turn has an opening therein 219 for receiving shaft 110.

[0025] Reference is now also made to Fig. 3, where in a driver assembly, generally indicated as 220 for coupling cyclic bearing 240a to motor housing 200. Driver assembly 220 includes a driver motor interface 222 coupled to motor housing 200, between housing top 202 and housing bottom 204. A lowerdrive link 224 is rotatable affixed to driver motor interface 222 at a first end and rotatable coupled a lower drive link 226 at a second end. In turn lower drive link 226 is rotatable mounted to a swash plate interface 228. in this way driver assembly 220, may expand and contract in length. Swash plate interface 228 is coupled to rotating swash plate 216.

[0026] Additionally, a control rod assembly, generally indicated as 250 includes a socket 254 for rotatably supporting therein a joint ball 252 attached to a rotor mount 234a. Socket 254 is affixed at a first end of a threaded rod 256. A second socket 258, has a second joint ball (not shown) disposed therein. Second joint ball is affixed to a swash plate interface 260 which in turn is affixed to the rotating swash plate 216 of cyclical bearing 240.

[0027] It should be noted that a second control rod assembly couples second propeller 232b to cyclic bearing 240. As will be described in greater detail below, movement in rotating swash plate 216 is translated to motor assembly 200 by driver assembly 220 and to the propellers by control rod assembly 250.

[0028] Motor assembly 200 may also include a collar 201 , and a bearing swivel j oint ball for facilitating movement. As will be described, under the control of a linkage, generally indicated as 600, cyclical bearing 240a may control the orientation of propellers 232a, 232b and movement of assemblies 200, 300 along shaft 110, but are not allowed to rotate about shaft 110.

[0029] Motor assembly 300 and associated cyclic bearing 232b are substantially the same structure as motor assembly 200, and cyclic bearing 232a, the difference being the reverse orientation of propellers 332a, 332b, relative to propellors 232a and 232b, to facilitate counter rotation operation between the two motors. Therefore, but for the description of the blades, the internal structures and linkages are the same.

[0030] Each stator 206 is energized by an on board battery (not shown), as known in the art. Each respective stator 206 is energized to a polarity opposite the other. In a preferred non limiting embodiment each magnet 206, of the respective motor assemblies, is energized by its own respective battery, each battery having a different polarization than the other. This causes the upper motor 200 to rotate propellers 232a, 232b in a first direction and lower motor 300 to rotate the propellors 332a, 332b in the opposite direction, although upper and lower motor assemblies 200, 300 can be oriented vice versa, so long as both motors spin in opposite directions to each other. Preferably propellers 232a, 232b rotate in a clockwise direction and propellors 332a, 332b rotate in the counterclockwise direction. It should be noted that shaft 110 is stationary, motor assemblies 200, 300 do not move rotationally about the shaft 100 and both sets of propellors rotate about the shaft 1 10 and motor assembly 200 and motor assembly 300 are capable of moving along the axis of shaft 100, but not rotationally thereabout.

[0031] A linkage, general indicated as 600, is disposed within shaft 100 because shaft 100 does not rotate. Linkage 600, controls the operation of cyclic bearing 240, which in turn controls the orientation of propellers 232a, 232b, 332a an 332b respectively.

[0032] Linkage 600 couples cyclical bearing 240a to cyclical bearing 240b and to cyclical and pedal controls for operating the craft. An upper motor collective linkage includes a first bridge 610 having a first arm 610a coupled to non rotating swash plate 218 at a first position of upper cyclical bearing 240a. First bridge 610 has a second arm 610b coupled to non-rotating swash plate 218 of upper cyclical bearing 240a at a second position of upper cyclical bearing 240a; substantially 180 degrees from the first position. In a preferred non limiting embodiment the portion of first bridge 610 between first arm 610a and second arm 610b is not linear with arms 610a, 610b and forms a bridge for clearance of other linkage structure.

[0033] Upper cyclic bearing 240a includes a second bridge 612 having a first arm 612a coupled to non rotating swash plate 218 at a third position of upper cyclical bearing 240a. Second bridge 612 has a second arm 612b coupled to non rotating swash plate 218 of upper cyclical bearing 240a at a fourth position of upper cyclical bearing 240a; substantially 180 degrees form the third position. In a preferred non limiting embodiment the portion of second bridge 612 between first arm 612a and second arm 612b is not linear with arms 612a, 612b and forms a bridge for clearance of other linkage structure.Additionally, in a preferred non limiting embodiment, first bridge 610 is disposed at a substantially right angle to second bridge 612, and as a result upper cycling bearing 240a is contacted at positions about ninety degrees apart from each other, for control at four positions in all of the direction of the compass.

[0034] It should be noted that for linkage 600, disposed within shaft 100, to operatively control cyclical bearing 240a, first bridge 610 and second bridge 612 must extend through shaft 100 at openings 902 shown, and three other of similar structure not shown. See Fig. 6. Because the inner structure of cyclic bearing 240a is stationary, non-rotating swash plate 218, the inner linkage can control cyclical bearing 240a from within shaft 100. Additionally, these specific linkages are formed as inverted bridge pairs to provide clearance relative to each other.

[0035] Similarly, for operating lower cyclical bearing 240b, a lower motor cyclic linkage includes a first bridge 712 having a first arm 712a coupled to a lower fixed swash plate 218a at a first position of upper cyclical bearing 240b. First bridge 712 has a second arm 712b coupled to the lower fixed swash plate 218a of lower cyclical bearing 240b at a second position of lower cyclical bearing 240b; substantially180 degrees from the first position. In a preferred non limiting embodiment the portion of first bridge 712between first arm 712a and second arm 712b is not linear with arms 712a, 712b and forms a bridge for clearance of other linkage structure.[0036J Lower motor collective linkage includes a second bridge 710 having a first arm 710a coupled to the lower fixed swash plate 218a at a third position of lower cyclical bearing 240b. Second bridge 710 has a second arm 710b coupled to the lower fixed swash plate 218 of lower cyclical bearing 240b at a fourth position of lower cyclical bearing 240b; substantially 180 degrees form the third position. In a preferred non limiting embodiment the portion of second bridge 710 between first arm 710a and second arm 710b is not linear with arms 710a, 710b and forms a bridge for clearance of other linkage structure. Additionally, in a preferred non limiting embodiment, first bridge 712 is disposed at a substantially right angle to second bridge 710, and as a result lower cycling bearing 240b is contacted at positions about ninety degrees apart from each other, for control at four positions in all of the direction of the compass.

[0037] Again, it should be noted that for linkage 600, disposed within shaft 100, to operatively control cyclical bearing 240b, first bridge 712 and second bridge 710 must extend through shaft 100 at openings 904 shown, and three other of similar structure not shown. See Fig. 6. Because the inner structure of cyclic bearing 240b is stationary, the fixed swash plate 218, the inner linkage can control cyclical bearing 240b from within shaft 100.

[0038] Now the linkages for operating the collective linkages will be described. Bridge 608 is connected to collective control lever 820 via linkage 880 at the end of the shaft 110 to make the motor assembly 200 slide along shaft 110. Movement of lever 820 translates to movement of bridge 608 which is fixed to motor assembly 200 through the wall of shaft 110 and enables the motor assembly 200 to slide along shaft 110 so that collective pitch of blades is performed.

[0039] Now the linkages for operating the cyclical linkages will be described. Bridge 610 is pivotably mounted about a pivot 606. A linkage 602 is affixed, at a first end, to bridge 610 away from the pivot point thereof. In this way movement of linkage 602 causes movement of the bridge about the pivot 606.

[0040] The cyclic movements of swash plates during operation of the invention is described below.Bridge 612 is rotatably mounted about a pivot 614. A linkage 620 is affixed, at a first end, to bridge 612 away from the pivot point thereof. In this way movement of linkage 620 causes movement of the bridge 612 aboutthe pivot 614. It should follow that movement of either bridge 610 or 612, causes cyclical bearing 240a to move; tilting off its access. Depending on how cyclical bearing 240a is moved, such movement is translated through cyclical bearing 240a via rotating swash plate 216 to driver assembly 220 and / or control rod assembly 250; controlling propellors 232a, 2332b.

[0041] Similarly, bridge 712 is rotatable mounted about a pivot 716. Linkage 602 is affixed at its other end to bridge 712. A second linkage 814 is rotatably affixed to bridge 712 about a pivot 827. It should be noted that linkage 602 is “lightning bolt” shaped, acting as a control rod so that it connects to bridge 610 on a different side of pivot 606, than the side of pivot 716 it connects to bridge 712. Thus movement of linkage 602 would cause cyclical bearing 240a to move in the opposite direction from cyclical bearing 240b.

[0042] Likewise, bridge 710 is rotatable mounted about a pivot 714. Linkage 620 is affixed at its other end to bridge 710. A second linkage 822 is rotatably affixed to bridge 710 about a pivot 824. It should be noted that linkage 620 is “lightning bolt” shaped, acting as a control rod, so that it connects to bridge 612 on a different side of pivot 614, than the side of pivot 714 it connects to bridge 710. Thus movement of linkage 620 would again cause cyclical bearing 240a to move in the opposite direction from cyclical bearing 240b.

[0043] Linkage 600 is connected to the pilot though cyclic controls coupled to linkage 600 by a respective cyclic control connectors 826, 810. Connector 802 is pivotably disposed about a pivot 804and connected at one end to a link 806. Link 806 is pivotably coupled by a pivot 805 to a lower rotor motor fix 840. Linkage 840 causes the rotor motor to slide along the shaft 110.

[0044] Control connection 819 is mounted about a pivot 812. A linkage 814 couples pivot 812 to bridge 712. In this way movement of linkage 814 is translated to movement of linkage 602, causing change in the orientation of cyclical bearings 240a, 240b, causing change in the orientation of the propellers.

[0045] Control connections 820, 802 connect foot pedal controls of a helicopter to linkage 600. Connector 820 is pivotably mounted about a pivot 828. When control connector 820 is moved up or down, it in turn slides the upper rotor motor assembly 200 on the shaft 110 so that collective pitch can be changed on the propellors 332a, 332b of the lower rotor motor assembly 300. Connector 802 does the same motion but for the lower rotor motor assembly 300. So if connectors 820, 802 are moved in unison, controlling the collective pitch of all blades 232a, 232b, 332a, 332b ,and the craft and pull into a hover (without any yaw movement (left or right as piloting)) . However, if you want to make a turn while in a hover, or just in general while flying forward, a differential in connectors 820 and 802 are input, so that you can execute a hovering turn, or a turn while in forward flight. This motion is actually very important to achieve turns in general. It’s a means of changing the collective pitch between upper and lower rotor motor assemblies 200, 300 respectively, otherwise the craft would be able to hover, but not make a hovering turn or forward flight turn.

[0046] Lastly pedal control 826 is mounted about a pivot to a collective control rod 822. Collective control rod 822 is coupled at its other end to collective rotor motor connect. 608.

[0047] By constructing a motor with the linkage as described above, a stationary shaft for mounting the motors may be used. The linkage and power system may be internal to the shaft, away from the elements, or dangers. The structure allows the use of electric motors rotating propellers in opposite directions, encouraging feathering when loss of power is experienced. Usage of the above motor with counter rotating motors removes the need for additional tail stabilization structure during fight, saving on energy usage. Lastly, use of the above linkage removes the need for complex controls such as left handed collective stick in the cockpit, which frees the user’s hand to adjust radios, change navigation and the like.

[0048] It will thus be seen that the obj ects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in carrying out the above method and in the construction set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

[0049] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Claims

CLAIMS1. A drive system for driving contra rotating motors comprise: a shaft; the shaft being stationary relative to a vehicle to which it is attached; a first motor mounted to the shaft, the first motor having a first stator mounted to the shaft, the first stator being a coil set, the first motor having a first motor housing rotatably mounted on the first stator; a first rotor blade mounted to the motor housing; a second rotor blade mounted to the motor housing; the motor housing rotating in a first direction when energized by a battery; a second motor mounted to the shaft coaxially with the first motor, the second motor having a second stator fixedly mounted to the shaft; the second stator being a coil set, the second motor having a second motor housing rotatably mounted on the stator, a third rotor blade mounted to the second motor housing; a fourth rotor blade mounted to the second motor housing; the second motor housing rotating in a second direction when energized by a battery; the second direction opposite to the first direction.

2. The drive system of claim 1, wherein the first motor housing rotates in a clockwise direction about the shaft and the second motor housing rotates in a counterclockwise direction about the shaft.

3. The drive system of claim 1, wherein at least the first stator is slidably mounted about the shaft.

4. The drive system of claim 3, wherein the second stator is slidably mounted about the shaft.

5. The drive system of claim 4, wherein the first stator includes a first magnet having a first polarization, and the second stator includes a second magnet having a second polarization, and the first polarization of the first magnet is opposite the second polarization of the second magnet.

6. The drive system of claim 1, further comprising a first non-rotating swash plate mounted about the shaft, a first rotating swash plate rotatably disposed about the first non-rotating swash plate; a first driver assembly coupling the first rotating swash plate and the first motor so that movement in the first rotating swash plate is translated to the first motor housing.

7. The drive system of claim 6, further comprising a second non-rotating swash plate mounted about the shaft, a second rotating swash plate rotatably disposed about the second nonrotating swash plate; a second driver assembly couples the second rotating swash plate and the second motor so that movement in the second rotating swash plate is translated to the first motor housing.

8. The drive system of claim 7, wherein first driver assembly at least one of expands or contracts in length changing the orientation of the first motor to the shaft.

9. The drive system of claim 8, wherein second driver assembly at least one of expands or contracts in length changing the orientation of the second motor to the shaft.

10. The drive system of claim 6, further comprising controls for controlling operation of the first motor; and a linkage for operatively linking the controls to the first non-rotating swash plate for controlling the orientation of the non-rotating swash plate relative to the shaft; the linkage being disposed within the shaft.1 1 . The drive system of claim 10, wherein the linkage for operatively links the controls to the first swash plate for controlling the orientation of the second non-rotating swash plate relative to the shaft.

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