| 摘要 |
A flow control valve comprises a valve body with a central flow passage containing a poppet releasably engagable with an annular valve seat, the poppet comprising a poppet head engageable with the valve seat and a central bore filled with an expansion member formed of silicone rubber or other substance having a coefficient of thermal expansion different from the material of the valve body and the poppet bore being closed by a stop member fixed in position relative to the valve seat, whereby the expansion or contraction of the expansion member causes the poppet head to move toward or away from the valve seat, increasing or decreasing flow through the valve. A spring adjustably pre-compresses the expansion member and balances the force created by the expansion of the expansion member, the axial position of the stop member being adjustable. The poppet head is notched to allow at least a trickle flow past the valve seat at all times to cause the expansion member to maintain a temperature approximately equal to the temperature of the fluid medium in the system. Two embodiments are shown, the first having the valve seat between the poppet head and the stop member such that increases in temperature of the fluid causes an increase of flow through the valve, and a second configuration in which the poppet head is between the valve seat and the stop member, such that increases in temperature of the fluid causes an decrease of flow through the valve.
|
