| 摘要 |
<p>A balloon (1) including a gas-inflatable bag (2) connectable to the ground via an elongate member (27) and containing a lighting device connectable to an electric power source, including control members (7, 15) responding to changes in the shape of the bag and/or the gas pressure therein by operating an actuating member (18) for actuating a switch assembly (25) between said lighting device and said electric power source and thereby switching the connection on or off on either side of at least one preset threshold. Said control members preferably include two counteracting springs.</p> |
