A shock absorber includes a piston which has at least one compression fluid passage and at least one rebound fluid passage. A compression valve assembly closes the at least one compression passage and a rebound valve assembly closes the at least one rebound passage. An interconnecting passage connects the at least one compression fluid passage and the at least one rebound fluid passage to define an open flow path through the piston.
1. A shock absorber comprising:
a pressure tube defining a working chamber;
a piston disposed within said working chamber, said piston dividing said working chamber into an upper working chamber and a lower working chamber;
a first compression passage extending through said piston between said upper and said lower working chambers;
a first compression valve assembly engaging a first pair of annular lands defined by said piston, said first compression valve assembly closing said first compression passage;
a first rebound passage extending through said piston between said upper and said lower working chambers;
a first rebound valve assembly engaging a second pair of annular lands defined by said piston, said first rebound valve assembly closing said first rebound passage; and
an interconnecting passage disposed radially inward from said first compression passage, radially inward from said first rebound passage and extending through said piston, said interconnecting passage defining a continuously open flow path extending from said upper working chamber through said entire first rebound passage through said interconnecting passage, through said entire first compression passage and into said lower working chamber;
a second compression passage disposed radially outward from said first compression passage and extending through said piston between said upper and said lower working chambers;
a second compression valve assembly engaging said piston, said compression valve assembly closing said second compression passage;
a second rebound passage disposed radially outward from said first rebound passage and extending through said piston between said upper and said lower working chambers; and
a second rebound valve assembly engaging said piston, said second rebound valve assembly closing said second rebound passage.
2. The shock absorber according to claim 1 , wherein said first compression valve assembly comprises a first valve disc engaging said piston, a first fluid chamber being formed between said first valve disc and said piston, said interconnecting passage being in communication with said first fluid chamber.
3. The shock absorber according to claim 1 , wherein said first rebound valve assembly comprises a first valve disc engaging said piston, a first fluid chamber being formed between said first valve disc and said piston, said interconnecting passage being in communication with said first fluid chamber.
4. The shock absorber according to claim 3 , wherein said first compression valve assembly comprises a second valve disc engaging said piston, a second fluid chamber being formed between said second valve disc and said piston, said interconnecting passage being in communication with said second fluid chamber.
5. The shock absorber according to claim 1 , further comprising a plurality of first rebound passages extending through said piston between said upper and said lower working chambers, said interconnecting passage being in communication with said plurality of rebound passages.
6. The shock absorber according to claim 1 , further comprising a plurality of first compression passages extending through said piston between said upper and said lower working chambers, said interconnecting passage being in communication with said plurality of compression passages.
7. The shock absorber according to claim 6 , further comprising a plurality of first rebound passages extending through said piston between said upper and said lower working chambers, said interconnecting passage being in communication with said plurality of rebound passages.
8. The shock absorber according to claim 1 , further comprising a plurality of first compression passages and a plurality of second compression passages.
9. The shock absorber according to claim 1 , further comprising a plurality of first rebound passages and a plurality of second rebound passages.
10. The shock absorber according to claim 9 , further comprising a plurality of first compression passages and a plurality of second compression passages.
11. The shock absorber according to claim 1 , wherein said first compression passage, said first rebound passage and said interconnecting passage define a flow path between said upper and said lower working chambers that is always open.
12. The shock absorber according to claim 1 , wherein said piston has a first side disposed adjacent said upper working chamber and a second side disposed adjacent said lower working chamber, said continuously open flow path extending from said first side to said second side then from said second side to said first side and then from said first side to said second side.