Fluid pressure control system

Claim 2

A two-hand fluid pressure control system comprising a pressurized fluid source, first and second valves normally urged to first positions and individually manually actuatable to second positions, a third valve normally urged to a first position and actuatable to a second position and including an inlet and an outlet, first timing means responsive to the actuation of said first valve for actuating said third valve a predetermined interval following said first valve actuation, second timing means responsive to the actuation of said second valve for effecting the flow of the pressurized fluid to said third valve inlet for a predetermined interval, actuating means responsive to the pressure at said third valve outlet, said first and second valves including first inlets connected to said fluid source and second inlets connected to exhaust, said first valve first position connecting said respective outlet and first inlet and said second valve first position connecting said respective outlet and second inlet, said first timing means including an actuating cylinder for said third valve and means controlling a flow control device connecting said third valve actuating cylinder to said first valve outlet, and said second timing means including an inlet connected to said second valve outlet and an outlet connected to said third valve inlet and a normally open valve device between said second timing means outlet and inlet closable after a predetermined interval in response to a predetermined pressure at said timing means inlet, a fourth valve including a first actuating cylinder and an opposing second actuating cylinder defining said actuating means, means connecting said fourth valve first cylinder to said first valve outlet, and means connecting said fourth valve second cylinder to said third valve outlet.

Claim 3

The control system of claim 1, including a machine-actuating cylinder including an inlet, said fourth valve including an outlet connected to said machine-actuating cylinder inlet and first and second inlets connected to said pressurized fluid source and exhaust respectively, and alternatively connected to said fourth valve outlet in response to the pressure differential in said fourth valve-actuating cylinders.

Claim 4

The control system of claim 1, including a double acting machine-actuating cylinder having opposing first and second inlets, said fourth valve including first and second outlets connected to said machine-actuating cylinder first and second inlets respectively and first and second inlets connected to said pressurized fluid source and exhaust respectively, and alternatively connected to respective outlets of said fourth valve in response to the pressure differential in said fourth valve-actuating cylinders.

Claim 5

The control system of claim 1, wherein said means connecting said fourth valve first cylinder and said first valve outlet includes a shuttle valve.

Claim 6

The control system of claim 1, wherein means connecting said fourth valve first cylinder and said first valve outlet includes a shuttle valve, and comprising a fifth valve including first and second inlets connected to said pressurized fluid source and exhaust respectively, and an outlet connected to said shuttle valve and alternatively to said fifth valve first and second inlets, a machine-actuating cylinder including an inlet, said fourth valve including an outlet connected to said machine-actuating cylinder inlet and first and second inlets connected to said pressurized fluid source and exhaust respectively and alternatively connected to said fourth valve outlet in response to tHe pressure differential in said fourth valve-actuating cylinders, and means response to a condition of said machine for actuating said fifth valve.

Claim 7

A two-hand pressure control system comprising a pressurized fluid source, first and second valves normally urged to first positions and including means for individually manually actuating said first and second valves to second positions, and including outlets, first inlets connected to said fluid source, and second inlets connected to exhaust, said first valve first position connecting said respective outlet and first inlet, and said second valve first position connecting said respective outlet and second inlet, a third valve normally urged to a first position and actuatable to a second position and including an inlet and an outlet, first timing means responsive to the actuation of said first valve for actuating said third valve a predetermined interval following said first valve actuation and including an actuating cylinder for said third valve and means including a flow control device connecting said third valve actuating cylinder to said first valve outlet, second timing means responsive to the actuation of said second valve for effecting the flow of a pressurized fluid to said third valve inlet for a predetermined interval, said second timing means including an inlet connected to said second valve outlet and an outlet connected to said third valve inlet and a normally open valve device between said second timing means outlet and inlet closable after a predetermined interval in response to a predetermined pressure at said second timing means inlet, a fourth valve including a first actuating cylinder and an opposing second actuating cylinder, a shuttle valve having an outlet connected to said fourth valve first cylinder and a first inlet connected to said first valve outlet and an opposing second inlet, a fifth valve including first and second inlets, connected to said pressurized fluid source and exhaust respectively, and an outlet connected to said shuttle valve second inlet and alternatively to said fifth valve first and second inlets, a machine-actuating cylinder including an inlet, said fourth valve including an outlet connected to said machine-actuating cylinder inlet and first and second inlets connected to said pressurized fluid source and exhaust respectively and alternatively connected to said fourth valve outlet in response to the pressure differential in said fourth valve-actuating cylinders, and means responsive to a condition of said machine for actuating said fifth valve.

Claim 8

A two-hand pressure control system comprising a pressurized fluid source, first and second valves normally urged to first positions and including means for individually manually actuating said first and second valves to second positions, and including outlets, first inlets connected to said fluid source, and second inlets connected to exhaust, said first valve first position connecting said respective outlet and first inlet, and said second valve first position connecting said respective outlet and second inlet, a third valve normally urged to a first position and actuatable to a second position and including an inlet and an outlet, first timing means responsive to the actuation of said first valve for actuating said third valve a predetermined interval following said first valve actuation and including an actuating cylinder for said third valve and means including a flow control device connecting said third valve actuating cylinder to said first valve outlet, second timing means responsive to the actuation of said second valve for effecting the flow of a pressurized fluid to said third valve inlet for a predetermined interval, said second timing means including an inlet connected to said second valve outlet and an outlet connected to said third valve inlet and a normally open valve device between said second timing means outlet and inlet closable after a predetermined interval in response to a predetermined pressure at said second timing means inlet, a fourth valve including a first actuating cylinder and an opposing second actuating cylinder, a shuttle valve having an outlet connected to said fourth valve first cylinder and a first inlet connected to said first valve outlet and an opposing second inlet, a fifth valve including first and second inlets, connected to said pressurized fluid source and exhaust respectively, and an outlet connected to said shuttle valve second inlet and alternatively to said fifth valve first and second inlets, a machine-actuating cylinder including an inlet, said fourth valve including an outlet connected to said machine-actuating cylinder inlet and first and second inlets connected to said pressurized fluid source and exhaust respectively and alternatively connected to said fourth valve outlet in response to the pressure differential in said fourth valve-actuating cylinders, and means responsive to a condition of said machine for actuating said fifth valve.