| 摘要 |
<p>The pump for liquids comprises a pump unit (1) e.g. a displacement piston (3) in a cylinder (2). The unit is driven e.g. by an expandable element (22), whose geometry chan ges under the influence of an external heat source, preferably solar radiation. When the element reaches its maximum expansion, it is cooled by the liq. that has been displaced by the pump. The element may be a bi-metallic element, one side of which is connected with the piston or piston rod(4). Its other end bears without friction (26) on a fixed support (17).</p> |
