Abstract:
For manufacturing a catheter having an inner tube forming a first lumen and an outer tube arranged coaxially with the inner tube, a second lumen being formed between the inner tube and the outer tube, a mandrel is inserted for retaining the first lumen into the inner tube, and an ultrasonic horn is applied to the outer surface of the outer tube for oscillating ultrasonic waves, thereby fusion bonding the inner surface of the outer tube to the outer surface of the inner tube. The particular method permits easily bonding the inner tube and the outer tube to each other. Also, since thermal deformation is small, it is possible to manufacture a catheter, in which the obstacle to the inflow of the inflation fluid into the inflatable member is very small, and which exhibits a rapid response to inflation and deflation of the inflatable member.
Abstract:
A crank damper pulley structure of an internal combustion engine of a car in which the hub of a pulley, which is removably fixed to the tip of the engine crank shaft and transmits power to auxiliary machinery, such as an alternator, has therearound a damper mass and a damper rubber comprising a torsional damper. The hub has a cavity therein which opens to one end of the hub. A damper support is fixed in the cavity and a ring-like damper and a ring-like damper mass are superposed axially with the rubber being fixed to the mass and the support in order to constitute a ring-like dynamic damper disposed in the cavity which copes with bending vibration of the crank shaft.