| 摘要 |
<p>The invention relates to a four-port thermally responsive valve for valving two pairs of isolated fluid ports in response to predetermined temperatures. A single valve member is movably contained within a housing passageway and spring biased in a first position so that sealing surfaces at either end of the valve member are respectively engageable with and spaced from corresponding seating surfaces in the passageway for achieving initially open or closed valved conditions within each pair of fluid ports. A seal ring mounted in the passageway and surrounding the valve member isolates the first pair of fluid ports from the second pair of fluid ports thereby preventing fluid interaction therebetween. When predetermined temperatures are encountered, a thermally responsive actuator connected to the valve member by a rod overcomes the biasing force generated by the spring and moves the valve member to a position that simultaneously reverses the valved condition of each pair of fluid ports.</p> |
