摘要 |
<p>A check valve comprising a poppet urged by a conical spring to annularly seal uniformly around its entire periphery to assure more uniform cracking pressure about its entire periphery. The cracking pressure may be adjusted by means of an adjustable plate which reduces the length of the conical spring and thereby increase the amount of force exerted by the spring onto the poppet into sealing engagement, thereby increasing the cracking pressure.</p> |