| 摘要 |
<p>A set of push-on building bricks consist of cylindrical hollow units in ones, two or threes in line or in cruciform shape, each consisting of a boss-like spigot with a conical top and a hole in the centre. A bar can be pushed through the hole to hold units by friction and act as a shaft. The open end of each unit has a bore of a dia. to accept the spigot end of another and hold it by friction. The material for all components of such a set is a soft plastic which has good adhesion, form stability, wear resistance and is non-toxic. The size of each unit is such that it can be taken in the mouth by small children but not swallowed. High-pressure polyethylene has been found very suitable.</p> |
