Sprinkler with repelling magnets

1. A sprinkler comprising:

a first portion;

a second portion arranged to rotate in reciprocating motion in a plane about a vertical axis relative to said first portion, responsive to impingement of a water stream on said second portion;

at least a first magnet associated with said first portion; and

at least a second magnet associated with said second portion, said first and second magnets being magnetized to repel each other when in at least predetermined propinquity during azimuthal rotation of said second portion relative to said first portion in said plane, said magnets limiting said azimuthal rotation of said second portion relative to said first portion.

2. A sprinkler according to claim 1 and also comprising a spring and wherein said impingement of said water stream on said second portion drives said second portion to rotate in a first direction about said vertical axis relative to said first portion, said spring is operative to urge rotation of said second portion in a second direction about said vertical axis and said first and second magnets cooperate to at least limit impact of said second portion at the end of its rotation in said first direction.

3. A sprinkler according to claim 1 and also comprising a third portion and wherein said first portion is rotatable relative to said third portion.

4. A sprinkler according to claim 1 and wherein said first portion comprises a water outlet arranged to provide said water stream.

5. A sprinkler according to claim 1 and wherein said second portion includes a water stream deflector.

6. A sprinkler according to claim 1 and wherein said first portion is a non-fixed portion.