Abstract: A pipe coupler for coupling pipes of different kinds with a one or more crown partially flexible heads, integrated into the ends of the pipe coupler for accommodating grip rings and seals for coupling pipes of different kinds. The crown heads have planes at different levels that form grooves for accommodating the seals, and a backward trimmed cone-shape inner surface plane and flat plane for locking the grip rings inside corresponding recesses in the crown head. The external surface of the grip rings is also cone-shaped that corresponds the shape of the inner surface of the crown head and in friction contact with this inner surface. The grip ring blocks the seal from slipping out, and has sets of teeth for engaging with and locking to a pipe inside the coupler.

Abstract: A system for cleaning solar panels, the system comprising: a mobile assembly for cleaning solar panels, where the mobile assembly is movable over cover surface of the solar panels, a stationary assembly for moving the mobile assembly, where the stationary assembly is fixed relative the solar panels; a water feeding assembly for feeding water to the mobile assembly, the water feeding assembly connects to and is in fluid communication with the mobile assembly; and a control and command cabinet for controlling operation of the mobile assembly, stationary assembly and water feeding assembly, where the stationary assembly connects mechanically to the mobile assembly and is configured to travel the mobile assembly over the cover surface of the solar panels according to commands delivered from the control and command cabinet.

Abstract: A pipe coupler for coupling pipes of different kinds with a one or more crown partially flexible heads, integrated into the ends of the pipe coupler for accommodating grip rings and seals for coupling pipes of different kinds. The crown heads have planes at different levels that form grooves for accommodating the seals, and a backward trimmed cone-shape inner surface plane and flat plane for locking the grip rings inside corresponding recesses in the crown head. The external surface of the grip rings is also cone-shaped that corresponds the shape of the inner surface of the crown head and in friction contact with this inner surface. The grip ring blocks the seal from slipping out, and has sets of teeth for engaging with and locking to a pipe inside the coupler.