According to an embodiment, a coil spring is formed of a wire which is helically wound, and includes an end turn portion and an effective portion, and a surface of the wire in the end turn portion includes an area which is softer than a surface of the wire in the effective portion.

A steering column for a motor vehicle may include a supporting unit and a displacement unit. The supporting unit may be connectable to a chassis of the motor vehicle, and the displacement unit may be displaceable relative to the supporting unit along a displacement path in a crash event. The steering column may further include an energy absorption element positioned between the supporting unit and the displacement unit. In a crash event, the energy absorption element may absorb energy over the displacement path. In some examples, the energy absorption element includes local laser solidifications that help control an energy absorption level of the energy absorption element.

According to an embodiment, a coil spring is formed of a wire which is helically wound, and includes an end turn portion and an effective portion, and a surface of the wire in the end turn portion includes an area which is softer than a surface of the wire in the effective portion.

An exemplary shock absorber includes a damper tube, a damper piston, a piston shaft, and at least two different surface treatments. The damper tube includes an interior surface. The damper piston includes a piston surface that engages the interior surface. The piston shaft couples with the damper piston and includes a shaft surface that engages a fourth surface. The at least two different surface treatments are disposed on at least one of the interior surface and the shaft surface and create a corresponding plurality of coefficients of friction with at least one of the piston surface and the fourth surface respectively.

A method of producing an electrode-equipped plate spring of a railcar bogie includes: a resin removing step of partially irradiating a surface of fiber-reinforced resin, prepared by including electrically conductive fibers in resin, of a plate spring with a laser beam to partially remove the resin and partially expose the electrically conductive fibers; and an electrode forming step of attaching an electrode to an exposed region formed by partially exposing the electrically conductive fibers of the fiber-reinforced resin.

A MEMS component. The MEMOS component includes a micromechanical membrane spring including first and second membrane spring elements with an at least regional two-dimensional curvature. The first membrane spring element is mechanically coupled to the second membrane spring element such that a resulting spring force of the membrane spring is imparted by the first and second membrane spring elements. The membrane spring is integrated into a layer structure of the MEMS component such that the resulting spring force of the membrane spring acts substantially in the layer sequence direction of the layer structure. A device for preloading the membrane spring is configured to set an operating point of the membrane spring with respect to the spring characteristic curve using permanent elastic deflection of the membrane spring, such that the operating point is in an approximately linear spring characteristic curve range of the membrane spring with a slight gradient.

A steering column for a motor vehicle may include a supporting unit and a displacement unit. The supporting unit may be connectable to a chassis of the motor vehicle, and the displacement unit may be displaceable relative to the supporting unit along a displacement path in a crash event. The steering column may further include an energy absorption element positioned between the supporting unit and the displacement unit. In a crash event, the energy absorption element may absorb energy over the displacement path. In some examples, the energy absorption element includes local laser solidifications that help control an energy absorption level of the energy absorption element.

A damper assembly includes a damper tube having a tubular shape defining an inner surface and extending for an axial length. The damper assembly also includes a rod disposed at least partially within the damper tube, and a piston connected to the rod and slidably disposed within the damper tube and configured to contact the inner surface of the damper tube along a stroke region less than the axial length. The inner surface of the damper tube includes a hardened surface including martensite and extending along the stroke region and less than the axial length of the damper tube. A method of treating a damper tube includes directing a laser beam onto an inner surface of the damper tube along a stroke region and less than an axial length of the damper tube and to cause steel of the inner surface of the damper tube to form a hardened surface.

The present disclosure provides a method for manufacturing an impact energy absorbing component, and an impact energy absorbing component which achieve both high collision performance and excellent EA performance by local heating. A method for manufacturing an impact energy absorbing component is a method for manufacturing an impact energy absorbing component including a member formed by processing a steel plate, in which at least a part of a bent ridgeline generated by the processing is heated at a temperature of 600 C. to an AC1 point. An impact energy absorbing component is an impact energy absorbing component including a member formed by processing a steel plate, in which at least a part of a bent ridgeline generated by the processing has a Vickers hardness equal to or lower than a Vickers hardness of each of flat surfaces constituting the impact energy absorbing component.