Patent Application
20200198432
The present disclosure relates to suspension systems for use with beam axles, and more specifically to suspension systems that include a leaf-spring arrangement and a ride-height adjustment mechanism in parallel.
Vehicles include suspension systems connected between the wheels and the chassis. Suspension systems include springs, dampers, e.g., shock absorbers, linkages, etcetera that connect the wheels to the chassis in way that permits relative motion between the wheels and the chassis. The suspension system absorbs road disturbances to improve both vehicle dynamics and ride comfort.
Some suspension systems are active and allow the ride height to be increased or decreased on command. Air suspension systems are one example of an active suspension systems. Air suspension systems include pneumatic springs, e.g., flexible bellows, that are filled with air by an air compressor. The ride height may be increased or decreased by adding or removing air from the bellows.
According to one embodiment, a suspension system for use between a frame and a beam axle includes a ride-height adjustment mechanism connectable between the frame and the beam axle. The adjustment mechanism includes an upper spring seat configured to mount to the frame and a lower spring seat configured to mount to the beam axle. A coil spring is interposed between the upper and lower spring seats. An electromechanical actuator arrangement is configured to move the upper spring seat relative to the frame or the lower spring seat relative to the beam axle so that a distance between the frame and the beam axle can be increased or decreased. A leaf spring may be connected between the frame and the beam axle in parallel with the ride-height adjustment mechanism. The ride-height adjustment mechanism is configured to adjust ride height of the vehicle without modifying a spring rate of the coil spring. The actuator arrangement may include a linear actuator driven by an electric motor. In some embodiments, the adjustment mechanism further includes a body attachable to the beam axle and supporting the lower spring seat. The actuator arrangement is configured to axially move the lower spring seat relative to the body to adjust ride height. In other embodiments, the adjustment mechanism further includes a body attachable to the frame and supporting the upper spring seat. The actuator arrangement is configured to axially move the upper spring seat relative to the body.
According to another embodiment, a suspension system includes a frame, an axle, and a ride-height adjustment mechanism configured to move the frame relative to the axle. The adjustment mechanism includes a body fixed to one of the frame and the axle, a first spring seat fixed to the other of the frame and the axle, a second spring seat movably attached to the body, and a spring interposed between the first and second spring seats. An actuator arrangement is configured to axially move the second spring seat relative to the body. The ride-height adjustment mechanism is configured to adjust ride height of the vehicle without modifying a spring rate of the spring. The actuator arrangement may be electromechanical such as an electric motor. The suspension system may include a leaf spring connected between the frame and the axle and may include a damper, e.g., shock absorber, between the frame and the axle.
According to yet another embodiment, a suspension system for use with a beam axle includes a leaf spring connectable between a frame and a beam axle. An electromechanical ride-height adjustment mechanism is interposable between the frame and the beam axle and includes upper and lower spring seats and a spring interposed between the spring seats. An actuator arrangement, which may include an electric motor, is configured to move the upper and lower spring seats relative to each other to adjust a distance between the frame and the beam axle. The ride-height adjustment mechanism may be configured to adjust the ride height of the vehicle without modifying a spring rate of the spring. In some embodiments, the lower spring seat is attachable to the beam axle, and the ride-height adjustment mechanism further includes a body attachable to the frame. The upper spring seat is movably connected to the body, and the actuator arrangement is further configured to axially move the upper spring seat relative to the body to adjust a position of the upper spring seat relative to the frame. In other embodiments, the upper spring seat is attachable to the frame, and the ride-height adjustment mechanism further includes a body attachable to the beam axle. The lower spring seat is movably connected to the body, and the actuator arrangement is further configured to axially move the lower spring seat relative to the body to adjust a position of the lower spring seat relative to the beam axle.
Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the embodiments. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.
Referring to
Referring to
The ride-height adjustment mechanisms 34 change the ride height of the vehicle by adjusting the location of the coil spring 40 relative to the ground or frame 22 as opposed to increasing or decreasing a spring rate. That is, the spring rate of the suspension system 30 is not changed as the ride height is adjusted. This is in contrast to air suspension in which the spring rate changes response to inflation and deflations of the air bellows.
Referring to
Referring to
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments can be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics can be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes can include, but are not limited to cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and can be desirable for particular applications.
The following is a list of reference numbers shown in the Figures. However, it should be understood that the use of these terms is for illustrative purposes only with respect to one embodiment. And, use of reference numbers correlating a certain term that is both illustrated in the Figures and present in the claims is not intended to limit the claims to only cover the illustrated embodiment.
