A wheel assembly includes a wheel having an axle, and a constant force mechanism coupled to the wheel. The constant force mechanism includes a horizontal support, a horizontal carriage associated with the horizontal support, a vertical support oriented perpendicular with respect to the horizontal support, a vertical carriage associated with the vertical support, and a rigid arm that is pivotally coupled with the horizontal carriage, the vertical carriage, and the axle. The rigid arm is coupled with the vertical carriage at a point intermediate where the rigid arm is coupled with the horizontal carriage and the axle. The horizontal carriage is capable of being urged along the horizontal support, and the vertical carriage is capable of being urged along the vertical support.

A lift device includes a chassis, a rear leveling assembly coupled to a rear end of the chassis, and a front leveling assembly coupled to a front end of the chassis. The rear leveling assembly includes a first rear actuator and a second rear actuator. The first rear actuator and the second rear actuator are selectively engageable to facilitate providing active control of a rear pitch adjustment and a rear roll adjustment of the rear leveling assembly. The front leveling assembly includes a first front actuator and a second front actuator. The first front actuator and the second front actuator are (i) selectively fluidly couplable to facilitate providing passive control of a front pitch adjustment and a front roll adjustment of the front leveling assembly and (ii) selectively fluidly decouplable to facilitate providing active control of the front pitch adjustment and the front roll adjustment of the front leveling assembly.

A lift device includes a chassis having a first end and an opposing second end, a first actuator coupled to the first end of the chassis, a second actuator coupled to the first end of the chassis, a third actuator coupled to the opposing second end of the chassis, a fourth actuator coupled to the opposing second end of the chassis, and a control system. The control system is configured to fluidly couple at least two of the first actuator, the second actuator, the third actuator, and the fourth actuator, and fluidly decouple and actively control the at least two of the first actuator, the second actuator, the third actuator, and the fourth actuator.

A wheel assembly includes a constant force mechanism and a wheel coupled to the constant force mechanism. The wheel is displaceable in at least one dimension, and the constant force mechanism imparts a substantially constant force on the wheel in the dimension. In one aspect, the wheel is displaceable in a first regime and a second regime. For a wheel displacement in the first regime, the constant force mechanism imparts a substantially constant force on the wheel, and for a wheel displacement in the second regime, the constant force mechanism imparts a variable force on the wheel. The variable force can be linear or non-linear to the magnitude of the displacement in the second regime and is equal to or greater than the substantially constant force.

Embodiments include an industrial truck comprising a chassis, which is supported by at least two front wheels and by at least one rear wheel, a mast for a load-carrying apparatus, wherein the front wheels are rotatably arranged on wheel arms that protrude forwards from the mast support region of the chassis, and configured for suppressing and reducing vibrations, wherein at least one of the wheel arms, is split into at least two wheel arm portions, which are mounted by a bearing arrangement so as to be able to perform movements relative to one another, wherein relative movements of the wheel arm portions are influenced, in order to suppress or reduce vibrations.

An industrial conveyor vehicle with four wheels (4, 5), a vehicle chassis (2) and a rear axle (1) in the form of a pendulum axle (1), which is mounted in a pivot mounting (3) supported on the vehicle chassis (2) and can undergo pivoting movements within the range of a pivot angle about a pivot axis (a) that extends in the longitudinal direction of the vehicle. Depending on the situation driving situation, a maximum pivot angle (.sub.1, .sub.2) can be set which limits the pivoting movements.

The invention relates to a lifting machine (1) comprising a lifting arm (3), a rolling chassis (2) equipped with at least one front axle (5) and one rear axle (6), and a sensor for measuring the tilt of the lifting arm (3) in relation to the chassis (2), the rear axle (6) being pivotably mounted around an axis that is parallel to the longitudinal axis of the machine (1). The rear pivoting axle (6) is mounted to freely pivot inside an angular range defined by two abutments supported by said chassis (2), the front axle (5) is coupled to the chassis (2) by a pivoting connection with an axis that is parallel to the longitudinal axis of the machine (1) and is equipped with an activatable/deactivatable suspension (9) in order to allow the relative pivoting between the front axle (5) and the chassis (2) to be damped, said suspension (9) being deactivated at least when the angle value measured by sensor (4) for measuring the tilt of the lifting arm (3) is greater than a predetermined threshold value.

A floor suspension system for a material handling vehicle is provided. The floor suspension system includes one or more coupling assemblies to couple a battery compartment and an operator compartment of the material handling vehicle to a fork frame of the material handling vehicle. The one or more coupling assemblies each include a first pivot arm to pivotally couple the battery compartment to the fork frame, a second pivot arm to pivotally couple the operator compartment to the fork frame, and a coupling arm to couple the first pivot arm to the second pivot arm. The floor suspension system further includes a spring assembly having a spring pack pivotally coupled to the fork frame and the battery compartment.

The present disclosure includes independent suspension systems or members, as well as wheeled skid steer loaders or other power machines including the same, that couple each wheel to a machine frame using a four-bar linkage, with the four bars including the frame of the machine, an upper control arm, a lower control arm, and a wheel carrier link. Each control arm is pivotally attached to both the machine frame and one end of the wheel carrier link. The four pivots between the control arms and the wheel carrier link are configured to all be contained within cylinder defined by the outer diameter of the wheel rim, allowing for a compact structure with the wheel carrier link and at least part of the control arms being positioned within this volume when the loader is in a resting position.

A lift device includes a chassis, a boom pivotally coupled to the chassis, a first leveling assembly pivotally coupled to a first end of the chassis, a second leveling assembly pivotally coupled to an opposing second end of the chassis, and a control system. The first leveling assembly includes a first pair of actuators positioned to facilitate a first pitch adjustment and a first roll adjustment of the first end of the chassis. The second leveling assembly includes a second pair of actuators positioned to facilitate a second pitch adjustment and a second roll adjustment of the opposing second end of the chassis. The control system is configured to (i) actively control the first pair of actuators and the second pair of actuators during a first mode of operation, and (ii) actively control the first pair of actuators and facilitate passive control of the second pair of actuators during a second mode of operation.