A mobility vehicle may comprise a frame, a first pivot arm, a second pivot arm, and a suspension assembly. The first pivot arm may be coupled to the frame and coupled to a drive wheel. The second pivot arm may be coupled to the frame and coupled to a ground engaging caster wheel. The suspension assembly may be coupled to the frame. The suspension assembly may include a first spring assembly and a second spring assembly. The first spring assembly may be disposed about a first spring axis and coupled to the first pivot arm. The second spring assembly may be disposed about a second spring axis and coupled to the second pivot arm. The first spring axis and the second spring axis may be disposed relative to each other at an angle of no greater than about 150° when the mobility vehicle is operating on horizontal ground.

A mobility vehicle may comprise a frame, a first pivot arm, a second pivot arm, and a suspension assembly. The first pivot arm may be coupled to the frame and coupled to a drive wheel. The second pivot arm may be coupled to the frame and coupled to a ground engaging caster wheel. The suspension assembly may be coupled to the frame. The suspension assembly may include a first spring assembly and a second spring assembly. The first spring assembly may be disposed about a first spring axis and coupled to the first pivot arm. The second spring assembly may be disposed about a second spring axis and coupled to the second pivot arm. The first spring axis and the second spring axis may be disposed relative to each other at an angle of no greater than about 150° when the mobility vehicle is operating on horizontal ground.

A suspension system for a dual-axle wheels assembly, including a sub-frame, a first arm connected to the sub-frame and rotatable with respect to the sub-frame about a first axis, a first connector connected to the first arm and having a first connector axis about which a first wheel rotates when connected to the first connector, the first connector axis is parallel to the first axis, a second arm connected to the sub-frame and rotatable with respect to the sub-frame about a second axis that is parallel to the first axis, a second connector connected to the second arm and having a second connector axis about which a second wheel rotates when connected to the second connector, the second connector axis is parallel to the second axis, and a motion restrainer comprising a spring and a damper and interconnecting the first arm and the second ram.

A suspension system for a dual-axle wheels assembly, including a sub-frame, a first arm connected to the sub-frame and rotatable with respect to the sub-frame about a first axis, a first connector connected to the first arm and having a first connector axis about which a first wheel rotates when connected to the first connector, the first connector axis is parallel to the first axis, a second arm connected to the sub-frame and rotatable with respect to the sub-frame about a second axis that is parallel to the first axis, a second connector connected to the second arm and having a second connector axis about which a second wheel rotates when connected to the second connector, the second connector axis is parallel to the second axis, and a motion restrainer comprising a spring and a damper and interconnecting the first arm and the second ram.

Methods, systems, devices and apparatuses for a torsion bar system. The torsion bar system includes a first torsion bar. The first torsion bar is configured to adjust a ride height of a first wheel of a vehicle. The torsion bar system includes a first actuator. The first actuator is coupled to the first torsion bar. The first actuator is configured to control a load on the first torsion bar. The torsion bar system includes an electronic control unit. The electronic control unit is coupled to the first actuator. The electronic control unit is configured to set a position of the first torsion bar using the first actuator and based on the load on the first torsion bar.

Methods, systems, devices and apparatuses for a torsion bar system. The torsion bar system includes a first torsion bar. The first torsion bar is configured to adjust a ride height of a first wheel of a vehicle. The torsion bar system includes a first actuator. The first actuator is coupled to the first torsion bar. The first actuator is configured to control a load on the first torsion bar. The torsion bar system includes an electronic control unit. The electronic control unit is coupled to the first actuator. The electronic control unit is configured to set a position of the first torsion bar using the first actuator and based on the load on the first torsion bar.

An adjustable anti-roll bar arrangement for a vehicle, comprising a bracket configured to be mounted in a fixed relationship to a chassis or a an axle of the vehicle, a linear actuator connected to the bracket, a guided element, the linear actuator being configured to drive the guided element along a first geometrical axis, a supporting shaft mounted to the bracket and defining a second geometrical axis which has a different extension compared to the first geometrical axis, an anti-roll bar, and a stabilizer stay having a first end connected to the anti-roll bar, and a second end movably connected to and supported by the supporting shaft, the second end being also connected to the guided element such that when the linear actuator drives the guided element along the first geometrical axis, the second end follows the motion along the second geometrical axis. The invention also relates to a vehicle comprising such an arrangement.

A method for manufacturing a hollow spring member having a hollow steel spring rod having terminal sealed portions at both ends thereof. Each terminal sealed portion has a rotationally symmetric shape in which an axis passing through a center of the spring rod is an axis of symmetry. Each terminal sealed portion has an end wall portion including an end face; an arc-shaped smoothly curved surface between an outer peripheral surface of the spring rod and the end face, and a hermetically closed distal-end-center closure portion on the axis passing through the center of the spring rod. The method includes forming each of the end portions of the spring rod by forming a chamfered portion on an inner or outer peripheral side of the end portion of a hollow wire, the end portion having an opening portion at a distal end, heating the end portion of the hollow wire having the chamfered portion, and spinning the heated end portion to be gathered toward the axis from the outer peripheral side by a jig. The end wall portion, which includes the distal-end-center closure portion, is formed by the distal end of the end portion being joined together on the axis.

A method for manufacturing a hollow spring member having a hollow steel spring rod having terminal sealed portions at both ends thereof. Each terminal sealed portion has a rotationally symmetric shape in which an axis passing through a center of the spring rod is an axis of symmetry. Each terminal sealed portion has an end wall portion including an end face; an arc-shaped smoothly curved surface between an outer peripheral surface of the spring rod and the end face, and a hermetically closed distal-end-center closure portion on the axis passing through the center of the spring rod. The method includes forming each of the end portions of the spring rod by forming a chamfered portion on an inner or outer peripheral side of the end portion of a hollow wire, the end portion having an opening portion at a distal end, heating the end portion of the hollow wire having the chamfered portion, and spinning the heated end portion to be gathered toward the axis from the outer peripheral side by a jig. The end wall portion, which includes the distal-end-center closure portion, is formed by the distal end of the end portion being joined together on the axis.

A suspension system for a dual-axle wheels assembly, including a sub-frame, a first arm connected to the sub-frame and rotatable with respect to the sub-frame about a first axis, a first connector connected to the first arm and having a first connector axis about which a first wheel rotates when connected to the first connector, the first connector axis is parallel to the first axis, a second arm connected to the sub-frame and rotatable with respect to the sub-frame about a second axis that is parallel to the first axis, a second connector connected to the second arm and having a second connector axis about which a second wheel rotates when connected to the second connector, the second connector axis is parallel to the second axis, and a motion restrainer comprising a spring and a damper and interconnecting the first arm and the second ram.