TM 10-3930-653-14&P FLOW REGULATOR VALVE The flow regulator valve is located between the control valve and the high-pressure ports of the two lift cylinders, serving  both  as  a  flow  regulating  valve  while  forks  are  being  lowered  and  a  safety  device  if  rubber  hoses  between  the control valve and lift cylinders are damaged due to any reason.  The operation of the flow regulator valve is given below. See Fig.  16-13.  When the forks are raised, high-pressure oil led from the control valve flows into the chamber (A) and shifts the sleeve (6) to the left.  This opens the opening (G) to allow the high-pressure oil to flow along the two routes( A - B - G - D- E and A - B- C - D) and both paths lead to the lift cylinders.  not regulated in any amount.  When the forks begin to lower, oil discharged from the lift cylinders enters the chamber( E) and shifts the sleeve until it contacts the nipple. This  closes  the  opening(G)  so  that  oil  flows  through(  E).  (D).    (H),  (C),  (B)  and(A)  to  the  tank.    If  the  amount  of  oil discharged from the lift cylinders is increased, the pressure in the chamber( F) rises and moves the piston (5) to the right in  spite  of  the  spring  force,  narrowing  the  opening  (  H).    So  the  flow  of  oil  from  the  chamber  (D)  to  the  chamber(C)  is decreased so that the descending speed of the forks is controlled. Fig.  4-476.  Flow Regulator Valve 1. Reacting spring 6. Snap ring 2. Case 7. Sleeve 3. Piston 8. Spring 4. Orifice plate 9. "O"-ring 5. Washer 10. Nipple 4-240