| 摘要 |
<p>A flow divider valve assembly and a power assisted steering system therewith. A spool (1) is axially slidable in a spool cylinder (2) within which it is biased (23, 24) to a neutral condition in which two control ports (13, 16) are open. A first of the control ports (13) is in a first fluid line which extends from an inlet port (8) by way of a first auxilliary chamber (11) to an outlet port (15) and the second control port (16) is in a second fluid line which extends from the inlet port (8) by way of a second auxilliary chamber (12) to a second outlet port (18). The outlet ports (15, 18) can be connected to opposite sides of a power assisting ram in a steering system. Communicating with the first fluid line downstream of the first control port (13) is a first primary chamber (19) formed on one side of the spool (1) and communicating with the second fluid line downstream of the second control port (16) is a second primary chamber (21) formed on the opposite side of the spool (1). The control ports (13, 16) are controlled by the spool (1) so that if fluid flow is resisted at one of the outlet ports (15, 18) fluid pressure develops in the primary (19, 21) and secondary (11, 12) chambers associated with that fluid line to subject the spool (1) to a pressure differential which causes it to be displaced axially from its neutral condition in a sense which progressively closes the control port (16, 13) of the other fluid line.</p> |
