A load insensitive time delay relay

Claim 2

A load insensitive relay for air or other compressible fluid operated systems, said relay comprising: means defining an Operating air passageway including an inlet to which operating air is supplied, an outlet from which such air is discharged to the load of the relay and a normally opened control vent port intermediate said inlet and outlet; a primary control member movable from a normal position spaced from said control vent port to a seating position blocking said control vent port; means to move said control member to said seating position in response to a fluid signal pulse; said operating air passageway including at a location between said inlet and said control vent, a nozzle type orifice to which operating air is passed and a bleed restrictor disposed immediately downstream from and normal to said restricted orifice, said restricted orifice and said bleed restrictor cooperating to discharge operating air to or to suck air from the atmosphere depending on the resistance of the load to which said operating air outlet port is connected.

Claim 3

A load insensitive time delay relay for air or other compressible fluid operated systems, said relay comprising: means defining an operating air passageway including an inlet to which operating air is supplied, an outlet from which such air is discharged to the load of the relay and a normally opened control vent port intermediate said inlet and outlet; a primary control member movable from a normal position spaced from said control vent port to a seating position blocking said control vent port; means defining with said control member a chamber having an inlet and a normally opened enabling vent port; an enabling member movable between a normal position spaced from said enabling port to a seating position blocking said enabling vent port; means defining with said enabling member a closed chamber having an inlet port on the side of the said enabling member opposite from the side thereof which seats against said enabling vent port; and means to supply control fluid signals to said members, respectively and including first and second divided passageways supplied by common control signal source, said first passageway being connected to the inlet of said closed chamber for moving said enabling member to its seating position against said enabling vent port, said second signal passageway including time delay means and being connected to the inlet port of the chamber defined with said control member to close said control vent port after said enabling vent port has been closed and thereby cause an increase in pressure at the outlet of said operating fluid passageway.

Claim 4

A load insensitive time delay relay for air or other compressible fluid operated systems, said relay comprising: means defining an operating air passageway including an inlet to which operating air is supplied, an outlet from which such air is discharged to the load of the relay and a normally opened control vent port intermediate said inlet and outlet; a primary control member movable from a normal position spaced from said control vent port to a seating position blocking said control vent port; means defining with said control member a chamber having an inlet and a normally opened enabling vent port; an enabling member movable between a normal position spaced from said enabling port to a seating position blocking said enabling vent port; means defining with said enabling member a closed chamber having an inlet port on the side of the said enabling member opposite from the side thereof which seats against said enabling vent port; and means to supply control fluid signals to said members, respectively and including first and second divided passageways supplied by common control signal source, said first passageway being connected to the inlet of said closed chamber for moving said enabling member to its seating position against said enabling vent port, said second signal passageway including time delay means and being connected to the inlet port of the chamber defined with said control member to close said control vent port after said enabling vent port has been closed and thereby cause an increase in pressure at the outlet of said operating fluid passageway.

Claim 5

The apparatus recited in claim 2 wherein said time delay means comprises a variable restrictor in series with an accumulator in said second signal passageway.

Claim 6

The apparatus recited in claim 2 wherein said operating air passageway includes between said inlet and said control vent, a restricted orifice to which operating air is passed and a bleed restrictor disposed immediately downstream from and normal to said restricted orifice, said restricted orifice and said bleed restrictor cooperating to discharge operating air to or to suck air from the atmosphere depending on the resistance of the load to which said operating air outlet port is connected.

Claim 7

The apparatus recited in claim 4 wherein said restricted orifice is defined by a nozzle.

Claim 8

The apparatus recited in claim 2 wherein said members are fluid impermeable flexible diaphragms.