Aircraft wheel with drive lugs

Abstract

The invention relates to an aircraft wheel (1) comprising a rim (3a, 3b) fixed to a central hub (5a, 5b) defining an axis of rotation (X) of the wheel. The wheel comprises at least one drive lug (15) extending from the hub and projecting in a direction substantially parallel to the axis of rotation of the wheel, cooperating with a drive member (17) to drive the wheel in rotation. A landing gear and an aircraft comprising such a wheel are provided. A method for driving such a wheel is also provided.

Description

Technical Field

[0001] The present invention relates to the field of motor wheels, in particular wheels for aircraft landing gear, intended to be driven in rotation by drive means attached to the landing gear. The invention also relates to aircraft landing gear and aircraft equipped with such wheels, as well as a method for driving an aircraft wheel in rotation. Background Art

[0002] In the field of aviation, aircraft are currently being equipped with devices for driving wheels in rotation, so that the aircraft can move on the ground without using its own main aircraft engines.

[0003] This is generally a matter of rotating the drive member and transmitting the rotational motion of the drive member to the wheel via the coupling interface.

[0004] An aircraft wheel comprises a rim fixed to a central hub defining the wheel's axis of rotation. To drive the wheel in rotation, according to document FR-A-2,996,167, the rim is provided with a plurality of claws extending laterally (i.e., parallel to the axis of rotation), projecting from the rim's periphery so as to have two parallel faces. The coupling interface then comprises forks, each of which is capable of overlapping one of the claws, so as to transmit a rotational torque by pressing the fork against one of the faces of the claw. This method of driving an aircraft wheel in rotation has the disadvantage of requiring a specific rim periphery and, therefore, the manufacture of a specific rim.

[0005] There are also known aircraft wheels that include two rim halves assembled with the aid of bolts regularly spaced about the wheel's axis of rotation, with the torque for the rotational drive being transmitted to the wheel via the bolts used to assemble the rims. While this method of driving the wheel in rotation does not require modification of the rim halves, considerable forces are generated at the level of the bolts, which can make the correct assembly of the rim halves questionable. Summary of the Invention

[0006] An object of the present invention is to provide a wheel which can be easily coupled to a member for driving the same in rotation and which requires only minor modifications to existing rims.

[0007] To achieve this object, the present invention provides an aircraft wheel comprising a rim fixed to a hub defining an axis of rotation of the wheel.

[0008] According to the invention, the wheel comprises at least one drive pin extending from the hub, the drive pin protruding in a direction substantially parallel to the axis of rotation of the wheel so as to cooperate with the drive member to drive the wheel in rotation.

[0009] Hence, the wheel may be driven in rotation only by a drive member rotating about the same axis of rotation as the wheel, the drive member being provided with an aperture arranged to receive an end portion of the drive pin.

[0010] According to a particular characteristic, the drive pin is generally cylindrical and is force-fitted into a hole in the hub.

[0011] In a particular manner, the drive pin comprises a collar forming an abutment against which said drive pin fits into the hole.

[0012] In a particular manner, the hole comprises a counterbore inside which the collar is housed.

[0013] In a particular manner, the hole comprises a rounded bottom.

[0014] According to another particular feature, the wheel comprises a plurality of drive pins that are symmetrically distributed about the axis of rotation of the wheel.

[0015] The invention also relates to a landing gear for an aircraft, comprising such a wheel and means for driving the wheel in rotation, comprising a drive member arranged to cooperate with a drive pin and to transmit a driving torque to the wheel via said drive pin.

[0016] According to particular features, the drive member comprises an aperture arranged to receive an end portion of the drive pin.

[0017] The drive member is screwed onto the hub in a specific manner.

[0018] The invention also relates to an aircraft comprising a support structure to which such an undercarriage is fastened.

[0019] The invention also relates to a method for driving such an aircraft wheel in rotation, wherein a rotational driving torque of the wheel is generated by a drive member and transmitted to the wheel via a drive pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be better understood from the following description, which is purely illustrative and non-limiting and should be read with reference to the accompanying drawings, in which:

[0021] [ Figure 1 ] Figure 1 is an axial cross-sectional view of an aircraft wheel according to a specific embodiment of the present invention;

[0022] [ Figure 2 ] Figure 2 yes Figure 1 a front elevation view of a central portion of an aircraft wheel shown in , illustrating the distribution of drive pins about the axis of rotation of the wheel;

[0023] [ Figure 3 ] Figure 3 yes Figure 1 A detailed view of region III of the aircraft wheel shown in ; and

[0024] [ Figure 4 ] Figure 4 yes Figure 2 Detailed view of an axial section according to plane IV-IV of an aircraft wheel shown in . DETAILED DESCRIPTION

[0025] refer to Figure 1 According to a particular embodiment of the present invention, an aircraft wheel 1 comprises two aluminum wheel halves 2a, 2b, each comprising an annular half-rim 3a, 3b; a half-hub 5a, 5b defining the wheel's axis of rotation X; and webs 4a, 4b coaxially connecting the half-rims 3a, 3b and the half-hubs 5a, 5b. The wheel half 2a comprises a housing formed in the web 4a, in which a sealing gasket 8 is disposed.

[0026] The wheel halves 2a, 2b come together parallel to the axis X and comprise centering surfaces to ensure their correct relative position. The wheel halves 2a, 2b are held in place by assembly bolts 9 arranged in facing holes formed in the webs 4a, 4b.

[0027] The bolts 9 are tightened in a known manner to assemble the wheel halves 2a, 2b after the tire 10 has been mounted on the rim halves 3a, 3b. In this position, the sealing gasket 8 is elastically compressed between the wheel halves 2a, 2b, thus preventing the gas contained in the volume delimited by the tire 10 and the rim halves 3a, 3b from escaping outside the wheel 1.

[0028] Each of the half-rims 3a, 3b has a free annular edge provided with an annular rim flange projecting radially towards the outside of the wheel 1. In a known manner, the rim flanges form lateral abutments to prevent the tyre 10 from running away.

[0029] The inner surface of the half-rim 3a extends toward the outer surface of the half-hub 5a and cooperates with the web 4a to define a space for receiving a stack of brake discs (not shown). This stack comprises a stator disc that does not rotate relative to the wheel axle, and a rotor disc having peripheral recesses, designated 11, for receiving rods fixed to the inner surface of the half-rim 3a. Each rod 11 extends along an axis parallel to the axis of rotation X of the wheel 1.

[0030] The inner surface of half-rim 3b faces the outer surface of half-hub 5b. A first, generally rectilinear projection 12 projects from this inner surface of web 4b towards the free edge of half-rim 3b, parallel to axis X. Thus, when wheel 1 is viewed along axis X, projection 12 defines a receiving surface that partially extends the rim flange and includes a hole in which an inflation valve 13 is fixed. A duct 14 extends through the hole that receives valve 13, allowing pressurized gas to be introduced into the volume delimited by tire 10 and half-rims 3a, 3b.

[0031] The hub halves 5a, 5b form a wheel hub which is pivotally received on the wheel axle by means of bearings 6, 7.

[0032] refer to Figure 2 and Figure 3 The wheel 1 comprises six drive pins 15, which are generally cylindrical and project laterally from the half-hub 5b in a direction substantially parallel to the axis of rotation X of the wheel 1. The pins 15 are symmetrically distributed around the axis X, each pin being fitted in a hole 16 in the half-hub 5b.

[0033] Pin 15 is made of a single piece of nickel and chromium alloy, such as that manufactured by Special Metals Ltd. Each pin 15 comprises a first cylindrical portion 15.1 and a second cylindrical portion 15.2, between which a collar 15.3 is provided.

[0034] The first portion 15.1 and the second portion 15.2 constitute the region where the pin 15 fits into the hole 16 and the region where the pin 15 couples with the first claw 17, respectively. The first portion 15.1 has a diameter d1 slightly larger than the diameter of the hole 16 and has a free end with a smaller diameter to facilitate centering of the pin 15 in the hole 16. The second portion 15.2 has a diameter d2 smaller than the diameter d1 of the first portion 15.1 and a length l1 along the axis X that is approximately twice the length l2 of the first portion 15.1 along the same axis.

[0035] The collar 15.3 forms a fitting abutment against the entry of the pin 15 into the hole 16 and abuts against the counterbore 18 at the entrance of said hole 16. The diameter d3 of the collar 15.3 is slightly smaller than the diameter of the counterbore 18 and its thickness A along the axis X is slightly smaller than the depth B of the counterbore 18 along the same axis, so that the collar 15.3 is housed inside the groove defined by the counterbore 18.

[0036] The hole 16 extends from the lateral face of the half-hub 5b parallel to the axis X towards the inside of the wheel 1 and comprises a rounded bottom 16.1 to reduce stress concentrations at said hole 16 and thus limit the initiation of cracks.

[0037] First claw 17 comprises a circular plate pressed against half-hub 5b and delimited by an axial projection forming a dog claw. The plate of first claw 17 includes six cylindrical through-holes 19, arranged to adjustably receive portion 15.2 of pin 15, thereby transmitting the driving torque generated by an unillustrated electric motor, driven in rotation about axis X of the second claw, to wheel 1. This second claw is mounted so as to be movable between a first position interacting with first claw 17 and a second position disengaged from the first claw 17. The diameter D of aperture 19 is slightly larger than the diameter d2 of second portion 15.2 of pin 15 and smaller than the diameter d3 of collar 15.3. In the operating position, claw plate 17 bears against half-hub 5b, causing collar 15.3 to be retained in counterbore 18, thereby limiting the risk of pin 15 being dislodged from bore 16.

[0038] like Figure 2 and Figure 4 As shown, twelve screws 20 arranged in pairs around the pin 15 hold the first claw 17 in its operating position. The screws 20 are screwed into threaded holes 21 provided for this purpose in the half-hub 5b. The centers of the screws 20 lie on a circle whose center lies on axis X and are aligned in pairs with the centers of the pins 15. The screws 20 pass through the plate of the first claw 17 via holes corresponding to the holes 21 formed in the plate. To limit the risk of tearing the threads of the threaded holes 21, attachment threads 22 are installed in the holes 21, which increase the tightening force exerted by the screws 20. It should be noted that the clearance between the screws 20 and the holes formed in the plate to receive them is greater than the spacing between the pin 15 and the holes formed in the plate to receive them, so that torque is transmitted through the pin 15 rather than the screws 20.

[0039] Of course, the invention is not limited to the embodiments described but covers any variant coming within the ambit of the invention as defined by the claims.

[0040] The rim can be made up of one or more parts.

[0041] The number and arrangement of the drive pins may vary from the described embodiment.

[0042] Although the drive pins herein have a cylindrical cross-section, other shapes are contemplated.

[0043] Although the drive pins here are force-fitted into the hub, other methods of securing these pins are also conceivable (screwing, bolting, gluing, welding, etc.).

[0044] The shape and size of the first claw portion may vary.

[0045] Although the wheels here are made of aluminum and the pins are made of a nickel and chrome alloy, other materials can be used.

[0046] Other ways of fixing the first claw to the rim half are conceivable (clip-type elastic joint, screw connection, etc.).

[0047] The above description of wheel of the present invention is applied to aircraft landing gear. Of course, it also can be used together with other types of vehicles, for example, used together with land vehicles.

[0048] Although the bottom of the hole is circular here, other shapes are conceivable (tubular, frustoconical, etc.).

Claims

1. An aircraft wheel (1) comprising two half wheels (2a, 2b) assembled together by bolts (9), each half wheel comprising: Half rims (3a, 3b), half hubs (5a, 5b) defining the axis of rotation (X) of the wheel, and half webs coaxially connecting the half rims and the half hubs to each other, the bolts being arranged in facing holes formed in the half webs, characterized in that the aircraft wheel comprises: a first claw (17) which is held in place in one of the half hubs (5b) by a screw (20) which is screwed into a hole (21) provided in one of the half hubs; and at least one drive pin (15) extending from one of the half hubs, the drive pin protruding in a direction substantially parallel to the axis of rotation of the aircraft wheel so as to cooperate with the first claw (17) so that the aircraft wheel is driven by rotation of the first claw without passing through the screw.

2. The aircraft wheel (1) according to claim 1, characterized in that The drive pin (15) is generally cylindrical and is force-fitted into a hole (16) formed in one of the half hubs (5b).

3. The aircraft wheel (1) according to claim 2, characterized in that The drive pin (15) comprises a collar (15.3) forming an abutment against which the drive pin is fitted into the hole (16).

4. The aircraft wheel (1) according to claim 3, characterized in that The hole comprises a counterbore (18) inside which the collar (15.3) is received.

5. The aircraft wheel (1) according to any one of claims 2 to 4, characterized in that The hole (16) comprises a circular bottom (16.1).

6. Aircraft wheel (1) according to any one of claims 1 to 4, characterized in that The aircraft wheel (1) comprises a plurality of drive pins (15) symmetrically distributed around the rotation axis (X) of the aircraft wheel (1).

7. Aircraft wheel (1) according to any one of claims 1 to 4, characterized in that The drive pin (15) includes an end portion received in an aperture (19) formed in the first claw (17).

8. An aircraft landing gear, comprising at least one aircraft wheel (1) according to any one of claims 1 to 7 and a drive device for driving the aircraft wheel to rotate, the drive device comprising an electric motor, the electric motor driving a second claw portion to rotate, the second claw portion being installed to be movable between a first position interacting with the first claw portion (17) and a second position disengaged from the first claw portion, so as to transmit the driving torque generated by the electric motor to the at least one aircraft wheel.

9. An aircraft comprising a support structure to which at least one aircraft landing gear according to claim 7 is fastened.

10. A method for driving an aircraft wheel (1) in rotation according to any one of claims 1 to 7, wherein: A rotational drive torque is applied to the first claw (17), and the rotational drive torque is transmitted to the aircraft wheel (1) via the drive pin (15).

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