초록 ▼

A port control member (80) is depressed by either a mechanical force (124) applied on it by the pilot (44), for moving it to meter pressure and flow from a supply pressure (72) to the wheel brakes (34) , or a hydraulic pressure force (128) applied following take-off, to activate the brakes (34) for

A port control member (80) is depressed by either a mechanical force (124) applied on it by the pilot (44), for moving it to meter pressure and flow from a supply pressure (72) to the wheel brakes (34) , or a hydraulic pressure force (128) applied following take-off, to activate the brakes (34) for stopping the wheels from spinning. The valve housing (62) defines an annular command pressure chamber (102) surrounding a portion of the port control member (80). The port control member (80) provides a larger pressure surface (128) to this chamber in the brake applying direction than it does in the opposite direction. This area differential results in pressure within the command pressure chamber (102) acting to move the port control member (80) in a brake applying direction. The command pressure chamber (102) may be connected to the wheel retract system (130) so that pressure is delivered into this chamber (102) automatically at the start of the wheel retraction operation.

대표청구항 ▼

A metering and despin valve for use in an aircraft to control pressure and flow to and from a wheel brake on a retractable landing gear, said valve comprising: a housing including wall means defining an elongated first chamber having an open end and a closed end, said housing further including a sup

A metering and despin valve for use in an aircraft to control pressure and flow to and from a wheel brake on a retractable landing gear, said valve comprising: a housing including wall means defining an elongated first chamber having an open end and a closed end, said housing further including a supply pressure port, a return pressure port, a brake port and a despin port; an elongated sleeve within said first chamber, said sleeve including an inner end, an outer end, and an elongated second chamber having an open inner end and an open outer end, said sleeve being inserted into the housing through the open end of the first chamber; retainer means at the open end of the first chamber for securing the sleeve within the housing; an elongated port control member within said second chamber, including a control end portion which projects from the second chamber, through and then outwardly beyond said retainer means; said port control member comprising a pair of axially spaced apart lands and an annular galley between the lands; said sleeve including first passageway means communicating the second chamber with the supply pressure port, second passageway means communicating the second chamber with the brake port, third passageway means communicating the second chamber with the return port and fourth passageway means communicating the second chamber with the despin port; said port control member having a retracted position in which said annular galley communicates the first passageway means, and hence the supply pressure port, with the second passageway means, and hence the brake port, and the second land means closes the third passageway means; said port control member having an extended position in which the first land closes the first passageway means and the annular galley connects the second passageway means, and hence the brake port, with the third passageway means, and hence the return port; said port control member functioning to meter brake pressure from the supply pressure port to the brake port in response to the port control member being moved from its extended position to its retracted position; said port control member comprising an annular command pressure chamber located between the second land and the control end portion; said control end portion being smaller in diameter than and first and second lands; said command pressure chamber being always in communication with the fourth passageway means; said command pressure chamber having a radial surface at the end thereof adjacent said second land, functioning as a pressure surface directed to produce a force acting on the port control member, in response to hydraulic pressure in the command pressure chamber, for urging the port control member toward a brake applying retracted position; and said port control member being inserted into the second chamber from the inner end of said second chamber, prior to the sleeve being inserted into the first chamber.