Pneumatic vibration damper between two system parts uses respective parts fixers and elastic body as connection plus external air source and flexible plate to control air chamber volumes.

摘要

The pneumatic vibration damper (11) as coupling between two parts of a system comprizes fixers (13,15) spaced on the respective system parts and linked by an elastic element (17), using an air chamber (53,63) to apply oscillating force between the two parts of the system by air pressure variations in response to a volume control (51) used to periodically regulate the chamber volumes. The pressure changes in the external air source (19) trip the control (51) such that the chamber volume increases whenever the air source absolute pressure exceeds a set value and correspondingly reduces chamber volume at values below this. The air chamber is linked to a direct-injection i.c. engine having stoichiometric and direct modes of operation and with the increase in chamber volume in stoichiometric mode and reduced volume in direct injection mode respectively. Actuation is by movable plate (47) forming one of the opposing chamber upper surfaces and used to control chamber voume using a tensioner (55) to switch the plate accordingly. The driving air chamber (51) as distinct from the working chamber (53) and linked to air source (19) applies air pressure to the plate (47) to switch it over the opposite way.