Patent ID: 11865051
Assignee: STRYKER CORPORATION
Field: Mechanical elements (Mechanical engineering)
Classification: CPC A  F | IPC A  F

Claim 18:
19. The patient handling apparatus according to claim 18, wherein said control valve assembly comprises:
a first chamber with a first inlet, a second inlet, an outlet, and a pilot piston assembly mounted for movement in said first chamber;
said pilot piston assembly including a pilot piston with a piston side facing said first inlet and a pilot rod, and said pilot rod extending from said first chamber into a second chamber sealed from the first chamber;
said second inlet of said first chamber being in fluid communication with said outlet of said first chamber so that fluid flows from said outlet of said first chamber;
said second chamber forming said pilot valve and including an inlet, an outlet, and a valve poppet movably mounted in said second chamber between a closed position wherein said inlet of said second chamber is not in fluid communication with said outlet of said second chamber and one or more open positions wherein said inlet of said second chamber is in fluid communication with said outlet of said second chamber; and
wherein when the fluid flow to said first inlet of said first chamber exceeds a preselected flow rate, back pressure at said first inlet of said first chamber will move said pilot piston and cause said pilot rod to move said valve poppet from said closed position to one of said open positions to allow fluid flow from said inlet of said second chamber to said outlet of said second chamber.