Abstract:
A mechanical device for use in the control of mechanical forces. The device comprising first and second terminals which, in use, are connected to components in a system for controlling mechanical forces. These terminals are moveable with respect to one another. The device further comprises means connected between the terminals to control the mechanical forces at the terminals. These mechanical forces are proportional to the relative acceleration between the terminals, wherein the proportionality term is either a fixed constant or a variable function.
Abstract:
Verstellbare Dämpfventileinrichtung (3) mit einer ersten verstellbaren Dämpfventilbaugruppe (43) für eine erste Durchströmungsrichtung und eine zweite verstellbare Dämpfventilbaugruppe (45) für eine zweite Durchströmungsrichtung, wobei beide Dämpfventilbaugruppen (43, 45) unabhängig voneinander verstellbar sind, wobei die erste Dämpfventilbaugruppe (43) nur für eine Durchströmungsrichtung eine Dämpfkraft erzeugt und die zweite Dämpfventilbaugruppe (45) in der Einstellung für die maximal große Dämpfkraft einen vom Dämpfmedium durchströmbaren Mindestquerschnitt (79) aufweist, so dass die zweite Dämpfventileinrichtung (45) eine Dämpfkraft in beiden Durchströmungsrichtungen erzeugt.
Abstract:
A suspension system has an isolator cylinder with a primary reservoir having a primary reservoir volume, a secondary reservoir having a secondary reservoir volume, a manifold and a primary duct fluidly connecting the primary and secondary reservoirs for controlling the flow rate of the fluid between the primary and secondary reservoirs, and optionally a valve for controlling a flow rate of a fluid through the duct, and a control system for operating the valve. A shock absorption system for a vehicle seat is provided comprising an isolator with at least one secondary pneumatic reservoir connected with a fluid duct to the primary reservoir of an isolator. The reservoir volumes, length and cross sectional area of the connecting duct and fluid flow control valves may be determined using methods including algorithms, experimental testing and models to determine the optimal values to achieve consistent shock mitigation across a range of seat loads.
Abstract:
A thermally driven piston assembly's housing has (i) a first material slidingly fitted therein, and (ii) at least one plug of a second material slidingly fitted therein and abutting the first material. The first material is one (e.g., a liquid crystal elastomer) that undergoes a stiffness change and/or a dimensional change when subjected to a temperature change in the temperature range of interest. When subjected to the temperature change while in the housing, the first material is restricted to changing dimensionally along a single dimension. The second material retains its shape and size throughout the temperature range of interest. As a result, the plug moves in the housing in correspondence with the dimensional change of the first material or the plug's movement is damped by the stiffness change of the first material.
Abstract:
A damping and shock absorbing method and apparatus for permanent or non-permanent use in the human body consists out of a shape memory alloy material which is cycled through the stress-strain hysteresis to dissipate energy for an effective damping. A sufficiently high pre-stress is applied to the damping element(s) to ensure that the damping working range is within the superelastic cycle. The damping apparatus can be designed to work in tension or compression or - by combination of compression and tension elements - both in tension and compression. Moreover, damping elements from a shape memory alloy can be designed to work also in flexion and extension as well in rotation. The damping apparatus can be designed to have a stroke and force suitable for use in the human body by the design, the structure and the chemical composition of the shape memory alloy and their pre-set properties, such as plateau stresses of the superelastic cycle depend on the ambient temperature, the force of damping elements can also be changed in-situ by changing the temperature of the damping elements. The damping elements out of a shape memory alloy can be combined with elastic elements out of other materials to achieve stress- strain behaviour more suitable for use in the individual human body.
Abstract:
Until now, a travelling brake was provided on the free end of the positioning arm, which dampened particularly the vibrations resulting from braking. According to the invention, vibrations are intercepted by a mechanically simple, hysteresis-free working hydraulic vibration damper thereby improving placement precision.