Vehicle air brake system with pressure separating brake housing
First Claim
1. A vehicle brake assembly for operating a brake acuator rod, said brake assembly includinga pressure housing with a first opening on one side thereof through which said actuator rod axially operates in a braking direction and a return direction opposite thereto,a diaphragm positioned for actuating said actuator rod in the braking direction,said pressure housing having a second opening on the side of said diaphragm opposite from said actuator rod for receiving pressure for actuating said diaphragm, anda two-way, open-center shuttle valve connected to said second opening having a first input port on one side of its center for receiving pressure from a service pressure supply and a second input port on the other side of its center for receiving pressure from an emergency pressure supply, a balance of service and emergency pressures keeping the shuttle of said open-center shuttle valve centered so that the common pressure of said service and emergency pressures provide actuating pressure against said diaphragm, an imbalance of said service and emergency pressures closing said two-way valve input port to the low pressure one of said imbalance service and emergency pressures while maintaining pressure from the high pressure one of said imbalance service and emergency pressures.
3 Assignments
0 Petitions
Accused Products
Abstract
A two-way check valve is utilized with each brake assembly to apply pressure against a single actuating diaphragm. One inlet port is connected to the service air supply and one inlet port is connected to the emergency air supply. Satisfactory pressure of either supply operates the brake connected to the brake assembly in a service manner, the loss of air pressure in either supply causing that supply to be closed by the check valve. Emergency air venting from a spring-biased piston with a pawl end causes the pawl to engage a rack surface of the brake actuator rod. Hence, no spring is used to power the brake actuator rod and brake connected thereto closed when there is a loss service air pressure.
17 Citations
17 Claims
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1. A vehicle brake assembly for operating a brake acuator rod, said brake assembly including
a pressure housing with a first opening on one side thereof through which said actuator rod axially operates in a braking direction and a return direction opposite thereto, a diaphragm positioned for actuating said actuator rod in the braking direction, said pressure housing having a second opening on the side of said diaphragm opposite from said actuator rod for receiving pressure for actuating said diaphragm, and a two-way, open-center shuttle valve connected to said second opening having a first input port on one side of its center for receiving pressure from a service pressure supply and a second input port on the other side of its center for receiving pressure from an emergency pressure supply, a balance of service and emergency pressures keeping the shuttle of said open-center shuttle valve centered so that the common pressure of said service and emergency pressures provide actuating pressure against said diaphragm, an imbalance of said service and emergency pressures closing said two-way valve input port to the low pressure one of said imbalance service and emergency pressures while maintaining pressure from the high pressure one of said imbalance service and emergency pressures.
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7. A vehicle air brake system, comprising
a service pressure supply of air, an emergency pressure supply of air, and at least one vehicle brake assembly for operating a brake actuator rod, said brake assembly including a pressure housing with a first opening on one side thereof through which said actuator rod axially operates in a braking direction and a return direction opposite thereto, a diaphragm positioned for actuating said actuator rod in the braking direction, said pressure housing having a second opening on the side of said diaphragm opposite from said actuator rod for receiving pressure for actuating said diaphragm, a two-way, open-center shuttle valve connected to said second opening having a first input port on one side of its center for receiving pressure from said emergency pressure supply, a balance of service and emergency pressures keeping the shuttle of said open-center shuttle valve centered so that the common pressure of said service and emergency pressures provide actuating pressure against said diaphragm, an imbalance of service and emergency pressures closing said two-way valve input port to the low pressure one of said imbalanced service and emergency pressures while maintaining pressure from said high pressure one of said imbalance service and said emergency pressures, and a signal supply of air including first valving means for metering service pressure supply to said first input port and second valving means for metering emergency pressure supply to said second input port.
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15. A vehicle air brake system connectable to a supply pressure of air and to service pressure air, comprising
a primary pressure reservoir having a check valve input connection for charging said primary pressure reservoir from the supply pressure of air, a delivery valve connected to the output of said primary reservoir for delivery of air at the pressure of said primary reservoir with the application of service pressure air to said delivery valve, a secondary pressure reservoir, a relay valve connected to said secondary reservoir having an input connection for charging said secondary reservoir from the supply pressure of air and an output connection at a pressure equal to the pressure of said secondary reservoir with the application of service pressure air to said relay valve, and a plurality of vehicle air brake assemblies, each operating a respective brake actuator rod, each of said brake assemblies including a pressure housing with a first opening on one side thereof through which said actuator rod axially operates in a braking direction and a return direction opposite thereto, a diaphragm positioned for actuating said actuator rod in the braking direction, said pressure housing having a second opening on the side of said diaphragm opposite from said actuator rod for receiving pressure for actuating said diaphragm, and a two-way, open-center shuttle valve connected to said second opening having a first input port on one side of its center for receiving pressure from said primary reservoir via said delivery valve and a second input port on the other side of its center for receiving pressure from said secondary reservoir via said second output connection of said relay valve for providing actuating pressure against said diaphragm, an imbalance of primary and secondary pressure closing said two-way valve input port to the low pressure one of said imbalanced primary and secondary pressures while maintaining pressure from the high pressure of one of said imbalanced primary and secondary pressures.
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17. A vehicle brake assembly for operating a brake actuator rod, said brake assembly including
a pressure housing with a first opening on one side thereof through which said actuator rod axially operates in a braking direction and a return direction opposite thereto, a diaphragm positioned for actuating said actuator rod in the braking direction, said pressure housing having a second opening on the side of said diaphragm opposite form said actuator rod for receiving pressure for actuating said diaphragm, and a two-way, open-center shuttle valve connected to said second opening having a first input port on one side of its center for receiving pressure from a service pressure supply and a second input port on the other side of its center for receiving pressure from an emergency pressure supply, a balance of service and emergency pressure keeping the shuttle of said open-center shuttle valve centered so that the common pressure of said service and emergency pressures provide actuating pressure against said diaphragm, an imbalance of service and emergency pressures caused by road shock to the vehicle alternately partially closing said two-way valve input port to the alternate low pressure one of said imbalance service and emergency pressures while maintaining pressure from the alternate high pressure one of said imbalance service and ecergency pressures to thereby provide steady overall braking pressure to said diaphragm.
Specification