Abstract: A pressure regulator valve has a valve spool slidably disposed in a valve bore to control the pressure in a hydraulic passage by exhausting excess fluid delivered to the passage. The valve also has a restricted passage which supplies fluid from a main inlet passage to the controlled fluid passage continuously. The restricted passage reduces the amount of valve spool movement required during normal pressure regulation.

Abstract: A transmission is operable to establish a plurality of forward speed ratios for a vehicle. The interchange of ratios is controlled by an electro-hydraulic valve arrangement and an inhibiting valve. If electrical power is discontinued and the transmission is operating in the highest speed ratio, the inhibit valve will maintain the highest speed ratio. At lower speed ratios the control will shift the transmission to the third highest speed ratio. During normal operation, the forced downshift from the highest ratio to the third highest ratio is delayed by the inhibit valve until the second highest ratio has been engaged. This prevents engine overspeed which might otherwise occur.