The present invention relates to a suspension arrangement for a tracked vehicle. The suspension arrangement includes a road wheel arm having a wheel axle portion for supporting a wheel of the vehicle and a pivot axle portion. The road wheel arm is pivotably journalled at the pivot axle portion to a housing that is fixable to the vehicle body. A torsion bar is connected to the pivot axle portion and a torsion tube is arranged to be connected to the vehicle body, with the torsion bar running through the torsion tube and arranged to be connected to the torsion tube. The modulus of elasticity of the torsion tube material is lower than the modulus of elasticity of the torsion bar material such that the maximum suspension travel is increased.

An overload suspension system configured for operative engagement to a vehicle having a first leaf spring and second leaf spring to provide auxiliary support to the vehicle when overloaded. A first control arm attached to a first torsion bar has a distal end positioned a separation distance from the first leaf spring. A second control arm attached to the second control arm has a distal end positioned substantially the same separation distance from the second leaf spring. The suspension system operates as an auxiliary suspension only when added weight to the vehicle deflects both leaf springs to contact a respective one of the control arms, thereby preserving the ride and suspension characteristics of the vehicle when the added weight is not present.

A suspension structure for an in-wheel motor drive device of the present invention includes an in-wheel motor drive device (10), a shock absorber (76), a torsion bar (81), and a stabilizer link (86), wherein: the shock absorber includes an upper spring seat (79a) provided in an upper end region of the shock absorber and a lower spring seat (79b) provided in a lower end region of the shock absorber and forming a pair with the upper spring seat; an upper end (87a) of the stabilizer link is arranged between a vehicle back edge (79d) of the lower spring seat and a vehicle front edge (79c) of the lower spring seat; and a lower end (87b) of the stabilizer link is arranged so as to overlap with a hub wheel (12) as viewed in an axial direction of the hub wheel.

A trailer for towing by a power vehicle is provided and generally includes a frame and a tandem wheel assembly. The frame forms an undercarriage chassis which the tandem wheel assembly is positioned there under. The undercarriage chassis includes a rear wheel assembly, a front wheel assembly, and an extension assembly moving the front wheel assembly between trailing position and a self-propelled position. At least one of the wheel assemblies is powered by a selectively engageable drive assembly including a motor, transmission, driveshaft, selectively engageable clutch and hub, to drive the rotation of at least one of the wheels.

A trailer for towing by a power vehicle is provided and generally includes a frame and a tandem wheel assembly. The frame forms an undercarriage chassis which the tandem wheel assembly is positioned there under. The undercarriage chassis includes a steerable rear wheel assembly, a steerable front wheel assembly, and an extension assembly moving the front wheel assembly between trailing position and a self-propelled position where the rear wheel assembly and the front wheel assembly are positioned to equally support the undercarriage chassis.

A torsion spring arrangement for a wheel suspension of a motor vehicle, including two torsion bars arranged coaxially one inside another and also a spring element, which is arranged axially-parallel to the two coaxial torsion bars and can be mounted on the motor vehicle body via a bearing position, wherein the radial outer hollow-cylindrical torsion bar can be mounted on the motor vehicle body side and is connected in a rotationally-fixed manner to an output lever fastenable on a wheel guiding element and the radial inner torsion bar is connected in a rotationally-fixed manner to the outer torsion bar and is connected in a rotationally-fixed manner via a coupling to the spring element.

A torsion spring assembly for a wheel suspension of a motor vehicle, including two torsion bars arranged coaxially one inside another and also a spring element, which is arranged axially-parallel to the two coaxial torsion bars, and can be mounted on the motor vehicle body via a bearing position, wherein the radial outer hollow-cylindrical torsion bar can be mounted on the motor vehicle body side and is connected in a rotationally-fixed manner to an output lever fastenable on a wheel guiding element and the radial inner torsion bar is connected in a rotationally-fixed manner to the outer torsion bar and is connected in a rotationally-fixed manner via a coupling to the spring element.

A trailer for towing by a power vehicle is provided and generally includes a frame and a tandem wheel assembly. The frame forms an undercarriage chassis and the tandem wheel assembly positioned under the undercarriage chassis. The tandem wheel assembly includes a rear wheel assembly and a front wheel assembly. An extension assembly is provided and moves the front wheel assembly between trailing position and a self-propelled position where the rear wheel assembly and the front wheel assembly are positioned to equally support the undercarriage chassis.

An axle cartridge member receives a pair of torsion stub axles at opposite lateral sides thereof. The torsion stub axles include elongated axle housings, which are sandwiched between two parallel plates to align the torsion stub axles with respect to one another. The cartridge member includes a central arch extending between the two torsion stub axles, which can provide additional ground clearance when the axle cartridge member is mounted to a trailer.

A stabilizer includes a stabilizer main body, and eyes formed on both ends of the stabilizer main body. Through-holes are formed in fastening surfaces of the eyes, respectively. The stabilizer main body is covered with a main body coating film. The eye is covered with an eye coating film whose thickness is less than a thickness of the main body coating film. An inner surface of the through-hole is covered with an inner surface coating film. An incomplete coating portion is formed at a part of the inner surface of the through-hole in a circumferential direction. The incomplete coating portion is located on an extension of a straight line connecting a center of the through-hole and the center of gravity of the stabilizer main body in a side view of the stabilizer main body.