Self-propelled undercarriage wheel having a low profile tire
An undercarriage wheel is disclosed comprising an axle member that supports a drive member, for example but not limited to a compact high torque electric motor, a wheel member driven by said drive member, and a tire attached to the wheel member, wherein the tire bulges in the width dimension of the wheel, wherein the drive member protrudes from the wheel member and thus occupies at least some of the additional width made available by the bulge of the tire. A further aspect of the invention is an undercarriage wheel that comprises an axle member that supports a drive member, for example but not limited to a compact high torque electric motor, a wheel member driven by said drive member, and a low-profile tire attached to the wheel member. Since the profile of the tire is low, additional space is available inside the wheel for the drive member. Preferably, the drive member occupies at least some of this additional space, and has sufficient power to be able to propel an aircraft to which the undercarriage assembly is attached, either alone or in combination with other self-propelled undercarriage assemblies attached to the aircraft.
1. A self-propelled aircraft undercarriage wheel assembly with external dimensions substantially equal to the external dimensions of a non-self-propelled standard aircraft undercarriage wheel assembly and including an axle supporting a wheel member, a compact high torque drive motor of a sufficient size to provide the necessary power to drive the aircraft on the ground, and a tire mounted on the wheel member, wherein the configurations of said wheel member and said tire mounted thereon produce a maximum volume within the wheel member to support the drive motor completely within the maximum volume produced, said tire configuration having a low profile and said wheel member having a diameter selected to mount said tire and produce said maximum volume.
2. The undercarriage assembly of claim 1 , wherein said self-propelled aircraft undercarriage assembly is sized to replace an existing undercarriage in an existing aircraft and fits into a space available in a fuselage bay of said existing undercarriage without negatively affecting the performance of said existing undercarriage.
3. The undercarriage assembly of claim 1 wherein said drive motor includes a fixed element connected to said axle and a driven element attached to said wheel member.
4. The undercarriage assembly of claim 1 in which at least one of said fixed element and said driven element is toroidally wound.
5. The undercarriage assembly of claim 1 , wherein said drive motor includes a driven element connected to said axle and a fixed element attached to said wheel member.
6. The undercarriage assembly of claim 1 , wherein said drive motor includes a first driven element internal to a fixed element and a second driven element external to said fixed element, and connecting means join said driven elements.
7. The apparatus of claim 6 , wherein said first and second driven elements are normal to each other.
8. The undercarriage assembly of claim 1 , wherein said drive motor includes more than one fixed element and more than one driven element.
9. The undercarriage assembly of claim 1 , wherein said drive motor includes fixed and driven elements that are interleaved.
10. The undercarriage assembly of claim 1 for an aircraft nose wheel.
11. The assembly of claim 1 additionally comprising one or more further wheel members, and wherein said drive motor rotates said wheel members.
12. The undercarriage assembly of claim 1 , in which said drive motor is a motor selected from the list comprising: an electric motor; an induction motor; a high phase order induction motor.
13. The undercarriage assembly of claim 1 , wherein said drive motor has a driven element and a fixed element and said driven element is external to said fixed element or internal to said fixed element.
14. A method for replacing an existing aircraft undercarriage wheel with an aircraft undercarriage wheel assembly as described in claim 1 , comprising the steps of:
(a) removing an existing undercarriage wheel from at least one fuselage bay of the aircraft;
(b) fitting into each said at least one bay, the self-propelled undercarriage assembly of claim 1 ; wherein said drive motor fits completely within the maximum volume produced by the low profile tire and the selected diameter of the wheel member.
15. The method of claim 14 , wherein said existing undercarriage wheel is a nosewheel.
16. The method of claim 14 , wherein the existing undercarriage wheel is removed from and replaced in all fuselage bays of the aircraft.
17. The method of claim 14 , wherein said existing undercarriage wheel is a wheel other than a nosewheel.