| abstract |
A pumping system comprising a pumping unit formed by a motor and a pump and adapted to raise a liquid from an underground level to a utilization level, a vaporizable fluid flowing in a closed circuit between a solar evaporator and a condenser, the said motor being disposed in the outgoing branch between the evaporator and the condenser, and a circulator being disposed in the return branch. The motor comprises a motor chamber which is connected by an internal bistable distributor either to the evaporator when said distributor is in an intake state, or to the condenser when said distributor is in an exhaust state, said motor chamber being partly limited by a flexible wall free to move between an intake stroke end position and an exhaust stroke end position, the flexible wall triggering the changes of state of the distributor by reaching its two end positions. The distributor is biased by a resilient means into one of its two stable states on either side of an unstable equilibrium position and is urged into its stable exhaust state by a flexible band tensioned by the flexible wall in the intake stroke end position, and is pushed into its stable intake state by the flexible wall in its exhaust stroke end position. The pumping unit also comprises a transmission chamber separated from the said motor chamber by the said flexible wall, and a pump unit having, on either side of a deformable diaphragm, a pump chamber provided with an intake valve drawing from the underground liquid level, and a delivery valve for delivery to the said utilization level and a reception chamber communicating with the said transmission chamber via a two-way pipeline, an incompressible transmission liquid complementally filling the said transmission and reception chambers as it flows in the two-way pipeline. |