Vehicle seat, particularly commercial vehicle seat

What is this patent about?

’232 is related to the field of vehicle seating, specifically the mechanical support structures used in commercial vehicle seats. It addresses the design of scissors-type stands that allow for height adjustment while maintaining stability and smooth movement along the seat frame.

The underlying idea behind ’232 is to eliminate mechanical play in a seat’s height-adjustment mechanism by using a dual-element bearing system that separates load-bearing from tolerance compensation. While a wheel handles the primary vertical forces, a specialized sliding block acts as a wedge against an angled guide rail. By applying lateral pressure to this slider, the system converts horizontal force into a vertical clamping effect, effectively sandwiching the mechanism into the frame to prevent rattling or wobbling.

The claims of ’232 focus on a bearing mechanism that combines a double cone wheel with a non-rotating slider. The slider features specific planar surfaces that meet at an edge and engage with an inclined guide track. This geometry ensures that as the rockers move longitudinally to adjust seat height, the slider maintains constant contact with the frame at a specific angle, while the double cone wheel centers itself on a triangular or roof-shaped rail to provide lateral and vertical stability.

In practice, the invention works by mounting the wheel and slider on a common cross bar that connects the scissor rockers. A spring inside the cross bar pushes the slider outward against the inclined surface of the frame. Because the guide is sloped, this outward pressure forces the entire assembly to seat firmly against the rails. The isosceles triangle profile of the lower guide rail acts as a self-centering track for the double cone wheel, ensuring the seat remains aligned even under heavy loads or during vibration.

This approach differs from prior solutions that relied solely on rollers, which often suffer from multi-directional backlash or require complex, multi-wheel assemblies to achieve stability. By replacing one of the rollers with a spring-loaded slider acting on an angled plane, the invention achieves a backlash-free state in both the vertical and transverse directions simultaneously. This design simplifies the bearing architecture while providing a more robust direct power flux from the seat occupant through to the vehicle chassis.