ELECTROMAGNETICALLY OPERATED COUPLER

Abstract

Wheel-side arrangement (10), comprising: a first shaft (26) supported on a carrier (12) attached to a vehicle frame with first coupling teeth (38); a second wave (28) ; a coil (50); a sleeve (32) rotatably attached to the second shaft (28), which is axially displaceable with respect to the first shaft (26), with second coupling teeth (34) which alternately engage and disengage the first coupling teeth (38) due to an electromagnetic field generated by exciting the coil (50), further comprising: an inner hub housing (16) which is attached to the carrier (12) and includes the coil (50), the sleeve (32), a piston (52), a thrust bearing (56) positioned axially between the piston (52) and the sleeve (32) for transmitting axial movement of the piston (52) to the sleeve (32) when the coil (50) is energized, and a spring (58) for returning the piston (52) to a disengaged position.

Description

[0001] The present invention relates to a wheel-side arrangement.

[0002] Half-shafts extending laterally from rear axle drive units (RDUs) of all-wheel drive vehicles (AWD vehicles, AWD - all wheel drive) with a transversely mounted front engine rotate continuously with the rear wheels, even when no torque is transmitted to the RDU.

[0003] This continuous rotation of the half-waves generates energy losses associated with the rotating mass of the half-waves and other RDU components, including parasitic pumping losses from internal components of the RDU.

[0004] Wheel-side arrangements are known from US 5 827 148 A, GB 703 942 A and CN 2 053 276 U.

[0005] It is necessary to disconnect the rear wheels from the RDU when no torque is required at the rear axle, thereby achieving improved fuel economy for the vehicle.

[0006] This problem is solved by the features of the independent patent claim. Advantageous embodiments of the invention are described in the dependent claims.

[0007] The invention will be better understood by reference to the following description in conjunction with the accompanying drawings, which show: Fig. 1 a perspective view showing a left wheel-side structure with electrical disconnect device; Fig. 2 a perspective longitudinal cross-section of the wheel-side structure of Fig. 1 by a diametrical plane showing the wheel-side structure separated from the half-shaft; Fig. 3 a perspective longitudinal cross-section of the wheel-side structure of Fig. 1 by a diametrical plane showing the wheel-side structure connected to the drive half-shaft; and Fig. 4 a perspective longitudinal cross-section of the piston arrangement 1 through a diametrical plane.

[0008] The Fig. 1 and Fig. Figure 2 shows a wheel-side assembly 10 comprising a wheel-side support 12 attached to a vehicle frame; a half-shaft 14 extending outwards and to the left for a RDU and its differential mechanism; an inner hub housing 16 fastened to the support 12 by bolts 18; and a wheel hub 20 supported on the support 12 by bearings 22, 23 and carrying wheel bolts 24. Although components for the left side of the vehicle are shown, a separating device is provided on both the left and right wheel-side structures, the right side being symmetrical to the left side.

[0009] As in Fig. As shown in Figure 2, the wheel-side axle shaft comprises an outer shaft 26, which is rotationally fixed to the wheel hub 20, and an inner shaft 28, which is attached to the half-shaft 14 and can rotate freely in the inner hub housing 16. The inner shaft 28 has provisions for a constant velocity joint on the inward side of the shaft and is provided with an external, axial splined connection 30.

[0010] A sliding sleeve 32 is attached to the inner shaft 28 by an internal axial spline that engages with the outer spline 30, allowing the sleeve 32 and the inner shaft 28 to rotate together as a unit, while the sleeve can move axially relative to the inner shaft. The sleeve 32 is formed with radially extending claw teeth 34, which are spaced at an angle about the axis 36 and are positioned at the outer end of the sleeve. The inner end of the outer shaft 26 is formed with radially extending claw teeth 38, which are spaced at an angle about the axis 36 and alternately engage and disengage with the claw teeth 34.

[0011] The inner shaft 28 is axially held in the wheel hub housing 16 by a retaining ring 40 and a spring washer 42, which are positioned on axially opposite sides of a sealed ball bearing 44. The retaining ring 40 prevents the ball bearing 44 from moving inwards. A shoulder 46 machined into the inner hub housing 16 prevents the ball bearing 44 from moving outwards. The inner shaft 28 has a half-shaft spring washer groove machined on its outer surface, facing outwards from the ball bearing 44. Once installed in the groove, the spring washer 42 prevents the inner shaft 28 from moving inwards.

[0012] An electromagnetic coil 50 made of electrically conductive wire is held against rotation by its attachment to the inner wall of the inner hub housing 16. When the coil 50 is energized with an electric current, an electromagnetic field generated by the coil moves a piston 52 outwards along the axis 36, causing the claw teeth 34 of the sleeve 32 to engage with the claw teeth 38 of the outer shaft 26, thus connecting the half-shaft 14 and the outer shaft 26 in a drive connection. When the claw coupling teeth 34 and 38 are engaged, the outer shaft 26 and the inner shaft 28 are rotatably engaged.

[0013] The bearings 54, 44 and the bearings 22, 23, which are positioned in the wheel-side structure 10, allow the shafts 26, 28 to rotate concentrically to each other and concentrically to the inner hub housing 16.

[0014] A return spring 58 is positioned to return the piston 52 and push the sleeve 32 into the disengaged position when the coil 50 is de-energized.

[0015] Fig. Figure 4 shows the piston 52, the sleeve 32, and the intermediate bearing 56, which allows free rotation of the sleeve relative to the piston and transmits axial force from the piston to the sleeve when the coil 50 is energized. The inner surface 60 of the sleeve 32 is formed with an internal axial spline that continuously engages with the external axial spline 30 on the internal shaft 28.

Claims

[1] Wheel-side arrangement (10), comprising: a first shaft (26) supported on a carrier (12) attached to a vehicle frame with first coupling teeth (38); a second wave (28) ; a coil (50); a sleeve (32) rotatably attached to the second shaft (28), which is axially displaceable with respect to the first shaft (26), with second coupling teeth (34) which alternately engage and disengage the first coupling teeth (38) due to an electromagnetic field generated by exciting the coil (50), further comprising: an inner hub housing (16) which is attached to the carrier (12) and includes the coil (50), the sleeve (32), a piston (52), a thrust bearing (56) positioned axially between the piston (52) and the sleeve (32) for transmitting axial movement of the piston (52) to the sleeve (32) when the coil (50) is energized, and a spring (58) for returning the piston (52) to a disengaged position. [2] Wheel-side arrangement (10) according to claim 1, further comprising: a second bearing (23) for supporting the second shaft (28) on the inner hub housing (16); and a third bearing (44) to support the second shaft (28) on the first shaft (26). [3] Wheel-side arrangement (10) according to claim 2, further comprising: a retaining ring (40) attached to the inner hub housing (16), which contacts an axial side of the second bearing (23); a spring ring (42) attached to the second shaft (28), which contacts the second bearing (23) on the axial side of the second bearing (23) opposite the retaining ring (40).

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