초록 ▼

A system for retarding the speed of a railcar comprises a brake; a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on the wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel of the railcar;

A system for retarding the speed of a railcar comprises a brake; a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on the wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel of the railcar; a hydraulic circuit provided with a pump arrangement for supplying hydraulic fluid to the hydraulic actuator; and a control circuit coupled to the hydraulic circuit for controlling the flow of hydraulic fluid to move the brake between the closed and open positions.

대표청구항 ▼

1. A system for retarding the speed of a railcar, the railcar comprising: a brake;a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on a wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel

1. A system for retarding the speed of a railcar, the railcar comprising: a brake;a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on a wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel of the railcar;a hydraulic circuit configured with a first manifold and a second manifold, and provided with a pump arrangement for supplying hydraulic fluid from a reservoir to the hydraulic actuator; anda control circuit coupled to the hydraulic circuit for controlling the flow of hydraulic fluid to move the brake between the closed position and the open position,wherein the pump arrangement includes a first pump and a second pump, the first pump being configured for supplying the hydraulic fluid to one end of the hydraulic actuator and providing powered movement of the brake to the closed position and at least the second pump being configured for supplying the hydraulic fluid to an opposite end of the hydraulic actuator and providing powered movement of the brake to the open position, andwherein the control circuit and the hydraulic circuit are configured to provide a non-powered movement of the brake from the closed position to the open position without hydraulic fluid being forced from the hydraulic actuator and without hydraulic fluid being supplied to the hydraulic actuator such that the hydraulic fluid from the one end of the hydraulic actuator is given a free path therefrom back to the reservoir defining a relaxed position for the hydraulic actuator. 2. The system of claim 1, wherein the closed position defines a Braking State, and the open position defines one of a Relaxed State and a Power Open/Flush State. 3. The system of claim 2, wherein the first pump and the second pump are interconnected together and are driven by a motor. 4. The system of claim 3, further comprising a hydraulic accumulator connected to the first pump, wherein the first pump is periodically energized to charge the hydraulic accumulator so that, upon de-energization of the first pump, the hydraulic accumulator provides pressurized hydraulic fluid which is used to provide powered movement of the brake to the Braking State. 5. The system of claim 3, wherein at least the second pump is used to provide powered movement of the brake to the Power Open/Flush State. 6. The system of claim 3, wherein the first pump and the second pump are used to provide powered movement of the brake to the Power Open/Flush State. 7. The system of claim 2, wherein the hydraulic actuator comprises a piston movably disposed in a cylinder, wherein pressurized hydraulic fluid enables the piston to extend from the cylinder into an extended position to move the brake into the Braking State, and wherein pressurized hydraulic fluid enables the piston to retract into the cylinder in a retracted position to move the brake into the Power Open/Flush State. 8. The system of claim 7, wherein the piston defines an orifice therethrough in communication with a check valve and wherein the orifice and the check valve facilitate flushing of hydraulic fluid from a rod-side of the cylinder to a cap-side of the cylinder when the piston is moved from the extended position to the retracted position in the Power Open/Flush State. 9. The system of claim 7, wherein the control circuit and the hydraulic circuit are operated to provide non-powered movement to the Relaxed State without supplying pressurized hydraulic fluid to the cylinder. 10. The system of claim 4, wherein the hydraulic circuit includes a cyclonic reservoir for holding a supply of hydraulic fluid, the cyclonic reservoir being in communication with the pump arrangement and configured for processing hydraulic fluid returned with entrained air in the hydraulic circuit. 11. The system of claim 10, wherein the first pump is connected to a first filter, a first clogging switch and a first filter check valve. 12. The system of claim 10, wherein the second pump is connected to a second filter, a second clogging switch and a second filter check valve. 13. The system of claim 11, wherein the first filter is connected to a first check valve and an unloader valve. 14. The system of claim 13, wherein hydraulic fluid flows through the first filter and the first check valve, and a ball valve for delivery to the hydraulic accumulator which is charged to a predetermined system pressure. 15. The system of claim 14, wherein the system pressure is transmitted to an accumulator isolator and a first pilot controlled solenoid valve connected to the accumulator isolator. 16. The system of claim 15, wherein the system pressure is further transmitted to a directional control solenoid valve and a second pilot controlled solenoid valve. 17. The system of claim 16, wherein system pressure is further transmitted to an unloader which enables the system pressure to operate the unloader valve such that a supply of pressurized hydraulic fluid is available at an outlet thereof. 18. The system of claim 17, wherein the unloader valve is in communication with a first flow diverter solenoid valve that is further in communication with a return filter connected to the cyclonic reservoir. 19. The system of claim 18, wherein the control circuit sends a signal to operate the first pilot controlled solenoid valve to enable flow of pressurized hydraulic fluid through the accumulator isolator to a pressure controlling arrangement which is located in the first manifold and is configured to respond to different signals sent from the control circuit to maintain a desired selected system pressure corresponding to a desired braking pressure for holding the brake in the closed position. 20. The system of claim 19, wherein the pressure controlling arrangement includes a pilot controlled proportional solenoid valve, a logic element and a pilot line connecting the pilot controlled proportional solenoid valve with the logic element. 21. The system of claim 20, wherein pressurized hydraulic fluid at the selected system pressure maintained by the pressure controlling arrangement is delivered to the hydraulic actuator to provide the powered movement of the brake to the closed position. 22. The system of claim 21, wherein during the powered movement of the brake to the closed position, the first pilot controlled solenoid valve, the directional control solenoid valve, and the pilot controlled proportional solenoid valve are energized. 23. The system of claim 22, wherein the first pilot controlled solenoid valve, the directional control solenoid valve, the second pilot controlled solenoid valve, the first flow diverter solenoid valve, and the pilot controlled proportional solenoid valve are de-energized when the brake is moved to the Relaxed State. 24. The system of claim 23, wherein the second pump and the second filter are in communication with a second check valve, a pilot controlled directional control valve and a second flow diverter solenoid valve. 25. The system of claim 24, wherein the second flow diverter solenoid valve is in communication with a cooler connected to the cyclonic reservoir. 26. The system of claim 25, wherein the second pilot controlled solenoid valve is energized to control the pilot controlled directional control valve such that pressurized hydraulic fluid is delivered to the hydraulic actuator to provide a powered movement of the brake to the open position. 27. The system of claim 26, wherein, should the pressurized hydraulic fluid become heated, the second flow diverter solenoid valve is energized to divert flow from the pilot controlled directional control valve to the cooler. 28. The system of claim 27, wherein, if the hydraulic accumulator is fully charged, the second pilot controlled solenoid valve and the first flow diverter solenoid valve are energized to permit combined hydraulic fluid flow from the first pump and the second pump to provide the powered movement of the brake to the open position. 29. The system of claim 2, wherein the brake includes a set of levers and return springs, and wherein, in the Relaxed State, the hydraulic fluid flows freely from a cap-side chamber of the hydraulic actuator to the reservoir such that weight of the levers and return force of the springs causes at least partial opening of the brake. 30. A system for retarding the speed of a railcar, the system comprising: a brake;a hydraulic actuator for moving the brake between a closed position in which the brake applies pressure on a wheel of a railcar, and an open position in which the brake does not apply pressure on the wheel of the railcar;a hydraulic circuit provided with a pump arrangement for supplying pressurized hydraulic fluid from a reservoir to the hydraulic actuator;a control circuit coupled to the hydraulic circuit for controlling the flow of pressurized hydraulic fluid to move the brake between the closed position and the open position; anda hydraulic accumulator connected to the pump arrangement wherein the pump arrangement is configured to deliver pressurized hydraulic fluid to charge the hydraulic accumulator before pressurized hydraulic fluid is provided to the hydraulic actuator so that the hydraulic accumulator provides pressurized hydraulic fluid which is used to provide movement of the brake to the closed position,wherein the pump arrangement includes a first pump and a second pump, the first pump being configured to charge the hydraulic accumulator for supplying the hydraulic fluid to one end of the hydraulic actuator providing powered movement of the brake to the closed position, and at least the second pump being configured for supplying the hydraulic fluid to an opposite end of the hydraulic actuator and providing powered movement of the brake to the open position,wherein the first pump is periodically energized to charge the hydraulic accumulator so that, upon de-energization of the first pump, the hydraulic accumulator provides pressurized hydraulic fluid which is used to provide movement of the brake to the closed position, andwherein the control circuit and the hydraulic circuit are configured to provide a non-powered movement of the brake from the closed position to the open position without hydraulic fluid being forced from the hydraulic actuator and without hydraulic fluid being supplied to the hydraulic actuator such that the hydraulic fluid from the one end of the hydraulic actuator is given a free path therefrom back to the reservoir defining a relaxed position for the hydraulic actuator. 31. A system for retarding the speed of a railcar, the system comprising: a brake;a hydraulic actuator for moving the brake between a closed position in which the brake applies pressure on a wheel of a railcar, and an open position in which a brake does not apply pressure on the wheel of the railcar;a hydraulic circuit provided with a pump arrangement for supplying pressurized hydraulic fluid from a reservoir to the hydraulic actuator;a control circuit coupled to the hydraulic circuit for controlling the flow of pressurized hydraulic fluid to move the brake between the closed position and the open position;wherein the hydraulic actuator comprises a piston disposed in a cylinder, wherein pressurized hydraulic fluid enables the piston to extend from the cylinder into an extended position to move the brake into the closed position, and wherein pressurized hydraulic fluid enables the piston to retract into the cylinder into a retracted position to move the brake to the open position,wherein the piston defines an orifice therethrough in communication with a check valve positioned in the piston and wherein the orifice and the check valve are configured to facilitate flushing of the pressurized hydraulic fluid from a rod-side of the cylinder to a cap-side of the cylinder when the piston is moved from the extended position to the retracted position so that the pressurized hydraulic fluid is recycled into the hydraulic circuit for cleaning the hydraulic fluid therein,wherein the pump arrangement includes a first pump and a second pump, the first pump being configured for supplying the hydraulic fluid to one end of the hydraulic actuator and providing powered movement of the brake to the closed position, and at least the second pump being configured for supplying the hydraulic fluid to an opposite end of the hydraulic actuator and provided powered movement of the brake to the open position, andwherein the control circuit and the hydraulic circuit are configured to provide a non-powered movement of the brake from the closed position to the open position without hydraulic fluid being forced from the hydraulic actuator and without hydraulic fluid being supplied to the hydraulic actuator such that the hydraulic fluid from the one end of the hydraulic actuator is given a free path therefrom back to the reservoir defining a relaxed position for the hydraulic actuator. 32. The system of claim 31, wherein the check valve and the orifice prevent flow of hydraulic fluid between the rod-side of the cylinder and the cap-side of the cylinder when the piston is moved into the extended position. 33. A system for retarding the speed of a railcar, the system comprising: a brake;a hydraulic actuator for moving the brake between a closed position in which the brake applies pressure to a wheel of a railcar, and an open position in which the brake does not apply pressure to the wheel of the railcar, the hydraulic actuator including a piston rod having a piston which is movable back and forth within a cylinder;a hydraulic circuit provided with a pump arrangement for supplying pressurized hydraulic fluid from a reservoir to the hydraulic actuator;a control circuit coupled to the hydraulic circuit for controlling the flow of hydraulic fluid to move the brake between the closed position and the open position;wherein the hydraulic circuit includes a pressure controlling arrangement responsive to different signals sent by the control circuit for selecting and maintaining a selected system pressure of the hydraulic fluid in the hydraulic circuit, and a back-pressure inducing check valve connected to the pressure controlling arrangement such that when the wheel enters the brake and forces the brake towards the open position, the pressure controlling arrangement reacts to an increase in the pressure of the hydraulic fluid and directs an amount of hydraulic fluid to the reservoir to avoid over-pressurization and maintain the selected system pressure, and the check valve directs a portion of the hydraulic fluid directed to the reservoir to a rod-side of the cylinder to prevent cavitation during a rapid movement of the piston rod, andwherein the pump arrangement includes a first pump and a second pump, the first pump being configured for supplying the hydraulic fluid to one end of the hydraulic actuator and providing a powered movement of the brake to the closed position, and at least the second pump being configured for supplying the hydraulic fluid to an opposite end of the hydraulic actuator and providing a powered movement of the brake to the open position, and wherein the control circuit and the hydraulic circuit are configured to provide a non-powered movement of the brake from the closed position to the open position without hydraulic fluid being forced from the hydraulic actuator and without hydraulic fluid being supplied to the hydraulic actuator such that the hydraulic fluid from the one end of the hydraulic actuator is given a free path therefrom back to the reservoir defining a relaxed position for the hydraulic actuator. 34. A system for retarding the speed of a railcar, the railcar comprising: a brake;a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on a wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel of the railcar;a hydraulic circuit configured with a first manifold and a second manifold, and provided with a pump arrangement for supplying hydraulic fluid to the hydraulic actuator; anda control circuit coupled to the hydraulic circuit for controlling the flow of hydraulic fluid to move the brake between the closed position and the open position,wherein the pump arrangement includes a first pump and a second pump, the first pump being used in providing powered movement of the brake to the closed position and at least the second pump being used in providing powered movement of the brake to the open position, andwherein the control circuit and the hydraulic circuit are configured to provide a non-powered movement of the brake to the open position,wherein the closed position defines a Braking State, and the open position defines one of a Relaxed State and a Power Open/Flush State,wherein the first pump and the second pump are interconnected together and are driven by a motor,further comprising a hydraulic accumulator connected to the first pump, wherein the first pump is periodically energized to charge the hydraulic accumulator so that, upon de-energization of the first pump, the hydraulic accumulator provides pressurized hydraulic fluid which is used to provide powered movement of the brake to the Braking State,wherein the hydraulic circuit includes a cyclonic reservoir for holding a supply of hydraulic fluid, the cyclonic reservoir being in communication with the pump arrangement,wherein the first pump is connected to a first filter, a first clogging switch and a first filter check valve,wherein the first filter is connected to a first check valve and an unloader valve,wherein hydraulic fluid flows through the first filter and the first check valve, and a ball valve for delivery to the hydraulic accumulator which is charged to a predetermined system pressure,wherein the system pressure is transmitted to an accumulator isolator and a first pilot controlled solenoid valve connected to the accumulator isolator,wherein the system pressure is further transmitted to a directional control solenoid valve and a second pilot controlled solenoid valve,wherein system pressure is further transmitted to an unloader which enables the system pressure to operate the unloader valve such that a supply of pressurized hydraulic fluid is available at an outlet thereof,wherein the unloader valve is in communication with a first flow diverter solenoid valve that is further in communication with a return filter connected to the cyclonic reservoir,wherein the control circuit sends a signal to operate the first pilot controlled solenoid valve to enable flow of pressurized hydraulic fluid through the accumulator isolator to a pressure controlling arrangement which is located in the first manifold and is configured to respond to different signals sent from the control circuit to maintain a desired selected system pressure corresponding to a desired braking pressure for holding the brake in the closed position,wherein the pressure controlling arrangement includes a pilot controlled proportional solenoid valve, a logic element and a pilot line connecting the pilot controlled proportional solenoid valve with the logic element,wherein pressurized hydraulic fluid at the selected system pressure maintained by the pressure controlling arrangement is delivered to the hydraulic actuator to provide the powered movement of the brake to the closed position,wherein during the powered movement of the brake to the closed position, the first pilot controlled solenoid valve, the directional control solenoid valve, and the pilot controlled proportional solenoid valve are energized,wherein the first pilot controlled solenoid valve, the directional control solenoid valve, the second pilot controlled solenoid valve, the first flow diverter solenoid valve, and the pilot controlled proportional solenoid valve are de-energized when the brake is moved to the Relaxed State, andwherein the second pump and the second filter are in communication with a second check valve, a pilot controlled directional control valve and a second flow diverter solenoid valve. 35. A system for retarding the speed of a railcar, the railcar comprising: a brake;a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on a wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel of the railcar;a hydraulic circuit configured with a first manifold and a second manifold, and provided with a pump arrangement for supplying hydraulic fluid from a reservoir to the hydraulic actuator; anda control circuit coupled to the hydraulic circuit for controlling the flow of hydraulic fluid to move the brake between the closed position and the open position,wherein the pump arrangement includes a first pump and a second pump, the first pump being configured for supplying the hydraulic fluid to one end of the hydraulic actuator and providing powered movement of the brake to the closed position and at least the second pump being configured for supplying the hydraulic fluid to an opposite end of the hydraulic actuator and providing powered movement of the brake to the open position,wherein the control circuit and the hydraulic circuit are configured to provide a non-powered movement of the brake from the closed position to the open position without hydraulic fluid being forced from the hydraulic actuator and without further hydraulic fluid being supplied to the hydraulic actuator such that the hydraulic fluid from the one end of the hydraulic actuator is given a free path therefrom back to the reservoir defining a relaxed position for the hydraulic actuator,wherein the closed position defines a Braking State, and the open position defines one of a Relaxed State and a Power Open/Flush State, andwherein the brake includes a set of levers and return springs, and wherein in the Relaxed State, the hydraulic fluid flows freely from a cap-side chamber of the hydraulic actuator to the reservoir such that weight of the levers and return force of the springs causes at least partial opening of the brake. 36. A system for retarding the speed of a railcar, the railcar comprising: a brake;a hydraulic actuator moving the brake between a closed position in which the brake applies braking pressure on a wheel of a railcar, and an open position in which the brake does not apply braking pressure on the wheel of the railcar;a hydraulic circuit configured with a first manifold and a second manifold, and provided with a pump arrangement for supplying hydraulic fluid to the hydraulic actuator; anda control circuit coupled to the hydraulic circuit for controlling the flow of hydraulic fluid to move the brake between the closed position and the open position,wherein the pump arrangement includes a first pump and a second pump, the first pump being configured for providing powered movement of the brake to the closed position and at least the second pump being configured for providing powered movement of the brake to the open position,wherein the control circuit and the hydraulic circuit are configured to provide a non-powered movement of the brake to the open position without hydraulic fluid being forced from the hydraulic actuator,wherein the closed position defines a Braking state, and the open position defines one of a Relaxed State and a Power Open/Flush State,wherein the first pump and the second pump are interconnected together and are driven by a motor,wherein a hydraulic accumulator is connected to the first pump, wherein the first pump is periodically energized to charge the hydraulic accumulator so that, upon de-energization of the first pump, the hydraulic accumulator provides pressurized hydraulic fluid which is used to provide powered movement of the brake to the Braking State,wherein the hydraulic circuit includes a cyclonic reservoir for holding a supply of hydraulic fluid, the cyclonic reservoir being in communication with the pump arrangement and configured for processing hydraulic fluid returned with entrained air in the hydraulic circuit,wherein the first pump is connected to a first filter, a first clogging switch and a first filter check valve,wherein the second pump is connected to a second filter, a second clogging switch and a second filter check valve,wherein the first filter is connected to a first check valve and an unloader valve,wherein hydraulic fluid flows through the first filter and the first check valve, and a ball valve for delivery to the hydraulic accumulator which is charged to a predetermined system pressure,wherein the system pressure is transmitted to an accumulator isolator and a first pilot controlled solenoid valve connected to the accumulator isolator,wherein the system pressure is further transmitted to a directional control solenoid valve and a second pilot controlled solenoid valve,wherein system pressure is further transmitted to an unloader which enables the system pressure to operate the unloader valve such that a supply of pressurized hydraulic fluid is available at an outlet thereof,wherein the unloader valve is in communication with a first flow diverter solenoid valve that is further in communication with a return filter connected to the cyclonic reservoir,wherein the control circuit sends a signal to operate the first pilot controlled solenoid valve to enable flow of pressurized hydraulic fluid through the accumulator isolator to a pressure controlling arrangement which is located in the first manifold and is configured to respond to different signals sent from the control circuit to maintain a desired selected system pressure corresponding to a desired braking pressure for holding the brake in the closed position,wherein the pressure controlling arrangement includes a pilot controlled proportional solenoid valve, a logic element and a pilot line connecting the pilot controlled proportional solenoid valve with the logic element,wherein pressurized hydraulic fluid at the selected system pressure maintained by the pressure controlling arrangement is delivered to the hydraulic actuator to provide the powered movement of the brake to the closed position,wherein during the powered movement of the brake to the closed position, the first pilot controlled solenoid valve, the directional control solenoid valve, and the pilot controlled proportional solenoid valve are energized,wherein the first pilot controlled solenoid valve, the directional control solenoid valve, the second pilot controlled solenoid valve, the first flow diverter solenoid valve, and the pilot controlled proportional solenoid valve are de-energized when the brake is moved to the Relaxed State,wherein the second pump and the second filter are in communication with a second check valve, a pilot controlled directional control valve and a second flow diverter solenoid valve,wherein the second flow diverter solenoid valve is in communication with a cooler connected to the cyclonic reservoir,wherein the second pilot controlled solenoid valve is energized to control the pilot controlled directional control valve such that pressurized hydraulic fluid is delivered to the hydraulic actuator to provide a powered movement of the brake to the open position,wherein, should the pressurized hydraulic fluid become heated, the second flow diverter solenoid valve is energized to divert flow from the pilot controlled directional control valve to the cooler, andwherein, if the hydraulic accumulator is fully charged, the second pilot controlled solenoid valve and the first flow diverter solenoid valve are energized to permit combined hydraulic fluid flow from the first pump and the second pump to provide the powered movement of the brake to the open position.