A buffer structure in which a plurality of buffer bodies separated from each other by intermediate disc means are in axial direction located one behind the other and with radial play are arranged in a tubular member which has one end closed and has a push rod slidably arranged in the other end portion of the tubular member. The disc means are preferably provided with peripheral annular flange means slidably engaging the inner wall surface of the tubular member and defining annular grooves receiving therein portions of adjacent buffer bodies.
A pneumatic system for launching aircraft wherein an elongated frame having pressurized interior chamber is volumetrically related and communicatively connected to a longitudinally-slotted cylinder supported within the frame so that expansion of air into the cylinder produces a desired thrust pressure therein that is equalized by the residual pressure external of the cylinder within the chamber. A piston member slidably contained within the cylinder is adapted to receive the compressed air and is connected to a shuttle for accelerating the aircraft to be launched. The shuttle is releasably restrained at the rearward end of the cylinder and is adapted to travel longitudinally through the slot which is dynamically sealed by a flexible strip as the shuttle passes through the slot to preserve thrust pressure within the cylinder. Means for braking the shuttle after launch include a hydraulic shock absorber connected to the frame at the forward end of the cylinder, and a longitudinal elastomeric member attached at one end thereof to the shock absorber within the cylinder. The elastomeric member is formed having a gradually reduced cross-sectional area from either end thereof so that upon impact by the moving shuttle, the longitudinal surface of the member expands against the inside of the cylinder to dissipate a portion of the kinetic energy therealong and provide sufficient dampening, in cooperation with the absorber, to effectively brake the shuttle near the forward end of the frame.
A volume spring element 152 is located inside the piston 10 which is open to the cylinder 20. The spring element 152 is surrounded by hydraulic liquid on all sides except at its surface 1521 at which the element 152 is attached to the piston 10. When the hydraulic pressure increases, the volume spring element is compressed thereby decreasing its volume. When the hydraulic pressure decreases, the volume spring element expands again. When the hydraulic cylinder is closed off by a valve, then the hydraulic liquid in the piston 10 and in the cylinder 20 is disposed in a closed-off space or chamber. Axial pressures on the cylinder cause a pressure increase in the hydraulic medium. This causes the volume of the volume spring element to be decreased and the piston to be moved axially by the amount corresponding to the decrease of the equally large oil volume in the piston. With the reduction of the hydraulic pressure, the volume spring element expands again causing an axial movement of the piston in a direction out of the cylinder 20. The volume spring element effects the shock absorption of a saddle support which can be hydraulically positioned.
A shock absorber has a cylindrical housing which encloses a plurality of axially aligned chambers. Each chamber is defined by two distinct partition walls disposed perpendicular to the axis of the housing. One partition wall of each chamber is axially fixed and the other is axially displaceable relative thereto. Each chamber is filled with a pad or pads of compressible foamed plastic material, and pads of material having different densities are disposed in each chamber or in different ones of the several chambers.
