Anti-skid brake control and actuator assembly

Claim 2

An assembly for use in an antiskid brake system comprising an actuator unit operable to relieve the pressure in at least a portion of the brake system, said actuator unit including a control member movable to relieve the brake pressure and a servomotor operable to effect movement thereof, said servomotor including a pressure operated member having a normal position and movable in response to a pressure differential on the opposite sides thereof, means connecting said pressure operated member to said control member to effect movement thereof, a control valve for controlling the pressure on one side of said pressure operated member, said control valve including means for applying atmospheric pressure to said one side of said pressure operated member when said pressure operated member is in said normal position and means operable to apply a vacuum to said one side of said pressure operated member in response to the receipt thereby of a skid signal, and a fluid pressure responsive valve for controlling the pressure on the other side of said pressure operated member, said fluid pressure responsive valve including means providing an atmospheric communication to said other side of said pressure operated member when said pressure operated member is in said normal position and means for effecting an increase in the area of the atmospheric communication with said other side of said pressure operated member in response to movement of said pressure operated member.

Claim 3

An assembly for use in an antiskid brake system as defined in claim 1 wherein said fluid pressure responsive valve includes at least one member movable due to a pressure differential acting thereacross, said pressure differential being created by movement of said pressure operated member.

Claim 4

An assembly for use in an antiskid brake system as defined in claim 1 wherein said fluid pressure responsive valve comprises a pair of valve members having an abutting relationship, said valve members being relatively movable with respect to each other and provide upon relative movement therebetween for fluid pressure communication to said other side of said pressure operated member.

Claim 5

An assembly for use in an antiskid brake system as defined in claim 3 wherein said valve members have an abutting relationship when said pressuRe operated member is in said normal position and further including, a valve seat engageable with one of said valve members when said pressure operated member is in said normal position, and means defining a venting passage through the other of said valve members to provide an atmospheric communication with said other side of said pressure operated member when said members are in abutting relationship.

Claim 6

An assembly for use in an antiskid brake system as defined in claim 1 wherein said control valve comprises an electrical coil and first and second valve parts movable relative to a vacuum port and an atmosphere port respectively, means biasing said valve parts to a position in which said first valve part blocks vacuum communication with said one side of said pressure operated member and said second valve part is spaced from said atmosphere port so that atmospheric pressure is applied to said one side of said pressure operated member when said coil is not energized.

Claim 7

An assembly for use in an antiskid brake system comprising an actuator unit operable to relieve the pressure in at least a portion of the brake system, said actuator unit including a control member movable to relieve the brake pressure and a servomotor operable to effect movement thereof, said servomotor including a pressure operated member having a normal position and movable therefrom in a first direction in a brake pressure relieving stroke and movable in a second direction opposite said first direction toward said normal position in a brake pressure increasing stroke, biasing means urging said pressure operated member to said normal position and effecting movement thereof in said brake pressure increasing stroke, means connecting said pressure operated member to said control member to effect movement thereof, a control valve for controlling the pressure on one side of said pressure operated member, said control valve including means for applying atmospheric pressure to said one side of said pressure operated member when said pressure operated member is in said normal position and means operable to apply a vacuum to said one side of said pressure operated member in response to the receipt thereby of a skid signal to effect movement of said pressure operated member against said biasing means in a brake pressure relieving stroke, and a pressure responsive valve for controlling the pressure on the other side of said pressure operated member, said pressure responsive valve including means providing an atmospheric communication to said other side of said pressure operated member when said pressure operated member is out of said normal position and means for effecting a decrease in the area of the atmospheric communication with said other side of said pressure operated member in response to movement of said pressure operated member toward said normal position.

Claim 8

An assembly for use in an antiskid brake system comprising an actuator unit operable to relieve the pressure in at least a portion of the brake system, said actuator unit including a control member movable to relieve the brake pressure and a servomotor operable to effect movement thereof, said servomotor including a pressure operated member having a normal position and movable therefrom in a first direction in a brake pressure relieving stroke and movable in a second direction opposite said first direction toward said normal position in a brake pressure increasing stroke, biasing means urging said pressure operated member to said normal position and effecting movement thereof in said brake pressure increasing stroke, means connecting said pressure operated member to said control member to effect movement thereof, a control valve for controlling the pressure on one side of said pressure operated member, said control valve including means for applying atmospheric pressure to said one side of said pressure operated member when said pressure operated member is in said normal position and means operable to apply a vacuum to said one side of said pressure operated member in response to the receipt thereby of a skid signal to effect movement of said pressure operated member against said biasing means in a brake pressure relieving stroke, and a pressure responsive valve for controlling the pressure on the other side of said pressure operated member, said pressure responsive valve including means providing an atmospheric communication to said other side of said pressure operated member when said pressure operated member is out of said normal position and means for effecting a decrease in the area of the atmospheric communication with said other side of said pressure operated member in response to movement of said pressure operated member toward said normal position.

Claim 9

An assembly for use in an antiskid brake system as defined in claim 6 wherein said pressure responsive valve comprises a pair of valve members having an abutting relationship when said pressure operated member is in said normal position, a valve seat against which one of said valve members engages when in its normal position, the other of said valve members having a venting opening for applying atmospheric pressure to the other side of said pressure operated member when in its normal position.

Claim 10

An assembly for use in an antiskid brake system as defined in claim 7 wherein said valve members move in response to fluid pressure forces acting thereacross and said other of said valve members moves from said valve seat to effect an increase in the area of the atmospheric communication to said other side of said pressure operated member when said pressure operated member moves in said first direction.

Claim 11

An assembly for use in an antiskid brake system as defined in claim 6 wherein said control valve comprises an electrical coil and first and second valve parts movable relative to a vacuum port and an atmosphere port respectively, means biasing said valve parts to a position in which said first valve part blocks vacuum communication with said one side of said pressure operated member and said second valve part is spaced from said atmosphere port so that atmospheric pressure is applied to said one side of said pressure operated member when said coil is not energized.