Abstract: Several embodiments are disclosed of an automatic shutoff valve apparatus for permitting removal, repair, or replacement of a control valve from a mounting base without deactivating a complete system. In addition, a redundancy arrangement is disclosed wherein the shutoff valve apparatus and at least two control valves are employed in parallel so that the device activated by the control valves can be maintained operative when one control valve malfunctions or is removed, repaired, or replaced.

Abstract: A safety brake for use on presses that provides a positive stop which is positioned so that its braking surfaces will be engaged if the press overtravels its normal home position due to failure of the standard clutch and brake system of the press. The braking surfaces of the emergency brake are moved to a released position when the press is energized to begin a cycle of its operation. Once the released braking surfaces have passed by each other during the normal cycle of press operation, they are returned to their braking positions so as to preclude overtravel of the press past its home position to any substantial degree if the conventional brake of the press should fail.

Abstract: Means for sensing a discrepant position between two normally closed valves of a double valve assembly used to control an industrial machine such as an air-operated press clutch and brake. The indicating means comprises switch means responsive to the movement of each of the valves and so positioned that the switch means is actuated very close to the closed position of each valve. The switch means controls power to solenoid-operated pilot valves for the two main control valves of the double valve assembly. By controlling the switch means immediately adjacent the closed valve positions, the safe or closed part of the cycle is monitored for these valves, which are in themselves stable because of their normally closed nature. The switch means may be either cam-operated mechanical switches, proximity switches, photoelectric sensors, or contacts directly engageable by the inlet valve elements and utilizing the valve body itself as part of the electrical circuit.

Abstract: A double safety valve for stamping presses and the like having a monitor responsive to asynchronous pressures, to disenable a press. The assembly comprises two valve stems each being radially supported by a piston at one end and by an outboard bearing at the other end. Each valve stem carries an inlet poppet valve adjacent one end, a spool valve on an intermediate portion and an exhaust valve adjacent the other end. Cross passages connect the inlet poppet valve of each valve stem in series with the spool valve of the other valve stem. A common outlet chamber receives pressurized fluid from both spool valves, this outlet chamber being connected in parallel to both exhaust valves. The assembly thus has the advantages of a double safety valve in which the inlet valves are in series and the exhaust valves in parallel, but is capable of being monitored by a monitor responsive to asynchronous pressures or movements.

Abstract: Means for sensing a discrepant position between two normally closed valves of a double valve assembly used to control an industrial machine such as an air-operated press clutch and brake. The indicating means comprises switch means responsive to the movement of each of the valves and so positioned that the switch means is actuated very close to the closed position of each valve. The switch means controls power to solenoid-operated pilot valves for the two main control valves of the double valve assembly. By controlling the switch means immediately adjacent the closed valve positions, the safe or closed part of the cycle is monitored for these valves, which are in themselves stable because of their normally closed nature. The switch means may be either cam-operated mechanical switches, proximity switches, photoelectric sensors, or contacts directly engageable by the inlet valve elements and utilizing the valve body itself as part of the electrical circuit.

Abstract: A double valve of the safety type for the control of equipment such as the clutch/brake of a press. The double valve comprises two four-way valves each having two supply and two working ports and an exhaust port. The valves are shiftable by fluid controlled means through a shuttle check valve. The arrangement is such that when either main valve is faulted, pressure will be removed from the clutch/brake motor and the fluid controlled shifting means will be disenabled due to the lack of synchronism between the main valves. This self monitoring function will prevent repressurization of the clutch/brake motor regardless of whether the unfaulted main valve continues to operate. The main valves are of the open center crossover type to prevent trapping of air at the working port for the clutch/brake motor in intermediate positions of the valves.

Abstract: Four poppet valves are mounted in a common machined body which has a single inlet port, a pair of working ports and a pair of exhaust ports. The body interior has four valve ports, two of which connect the inlet port to the two working ports and the other two connecting the working ports with the exhaust ports. The housing also has identically sized guide supports and piston chambers for the poppet valves. These may be chosen either as normally closed or normally open straight way valves in a variety of arrangements. With each arrangement one or more pilot valves, either straight way, three-way or four-way, normally closed or normally open, may be connected to the piston chambers. Thus, the valve system may be arranged to have a four-way function as controlled by a single normally closed three-way pilot valve, operate two independent fluid motors using two three-way pilots, or can be arranged for various other control functions.