Abstract: An on-board train brake safety monitoring and fault action system that compares actual train brake power with expected train brake power to provide real time reporting to the train driver of the margin between the actual brake power and a safe threshold. The system may be configured to automatically make a full service brake penalty if the actual brake system power is less than a safe brake power threshold, such as those required by government regulations, or to adjust the braking system to improve actual brake efficiency. The on-board train brake monitoring system may optionally receive data from wayside hot and cold wheel detector systems to augment the actual brake power measurements.

Abstract: An air dryer system for a locomotive having optimized purge air control over a twin tower desiccant-type air dryer. The computer controlled locomotive brake system is used to determine when the air dryer is being used and approximately how much air flow has actually passed through the active tower of the dryer using the air consumption state, the change of pressure in the second main reservoir, the air compressor on/off state, the total accumulated time of air flow since last purge cycle, and/or the calculated air flow through the air dryer since the last purge cycle. When the actual air flow reaches the capacity of the active tower of the air dryer, the computer controlled locomotive brake system commands the air dryer to perform a purge cycle. The system thus maximizes the use of each tower in the air dryer rather than switching according to a preset time period.

Abstract: A brake cylinder limiting valve having a first portion that determines actual brake cylinder pressure and a second portion that determines intended brake cylinder pressure based on brake pipe pressure reduction. The two portions are combined so that brake cylinder pressure will be vented if the actual brake cylinder pressure exceeds intended brake cylinder pressure by a predetermined threshold amount, which is preferably two and one-half times the brake pipe pressure reduction. An exhaust cut-off valve may be used to prevent venting of the brake cylinder pressure if it falls below a predetermined value.

Abstract: A brake cylinder maintaining system produces a brake cylinder reference pressure based on the difference between the brake pipe pressure and the auxiliary reservoir pressure and then feeds that pressure to a choke and a volume so that the ratio of the reference area of the choke to the volume of stored brake cylinder reference pressure is substantively equal to the ratio of a brake cylinder charging valve area to the brake cylinder volume. The resulting reference pressure may be used to adjust brake cylinder pressure by providing the reference pressure to a standard quick service limiting valve or to a relay that can selectively charge or exhaust the brake cylinder.

Abstract: A brake cylinder having a filament wound composite pressure cylinder and a composite plastic non-pressure head. The pressure cylinder and non-pressure head are secured together by a pair of mating flanges and a V-shaped band securely attached over the flanges. The band has a gap that is easily adjustable to position the gap at the lowest point and be in alignment with a series of radially extending grooves in the flange of the non-pressure head, thereby ensuring proper drainage. The non-pressure head may include an integrally formed opening with a bearing surface for a piston rod, a seat for a piston return spring, a scraper for a piston rod, and a series of internal ribs that provide for structural support and act as stop against a piston overtravel.

Abstract: An on-board train brake safety monitoring and fault action system that compares actual train brake power with expected train brake power to provide real time reporting to the train driver of the margin between the actual brake power and a safe threshold. The system may be configured to automatically make a full service brake penalty if the actual brake system power is less than a safe brake power threshold, such as those required by government regulations, or to adjust the braking system to improve actual brake efficiency. The on-board train brake monitoring system may optionally receive data from wayside hot and cold wheel detector systems to augment the actual brake power measurements.

Abstract: A system for variably controlling the purge cycle of a locomotive air supply system air dryer pre-filtration state. A sensor in the air inlet of the air dryer provides temperature information to a controller, which calculates an appropriate purge cycle time based on the saturation partial pressure of water vapor at the actual temperature of the air entering the air dryer and the operates the drain valve according to the particular purse cycle time.

Abstract: An air dryer system for a locomotive having optimized purge air control over a twin tower desiccant-type air dryer. The computer controlled locomotive brake system is used to determine when the air dryer is being used and approximately how much air flow has actually passed through the active tower of the dryer using the air consumption state, the change of pressure in the second main reservoir, the air compressor on/off state, the total accumulated time of air flow since last purge cycle, and/or the calculated air flow through the air dryer since the last purge cycle. When the actual air flow reaches the capacity of the active tower of the air dryer, the computer controlled locomotive brake system commands the air dryer to perform a purge cycle. The system thus maximizes the use of each tower in the air dryer rather than switching according to a preset time period.

Abstract: A system for controlling locomotive compressors in a multiple locomotive consist to optimize compressor life, cold weather operation, and maintenance schedules. Each compressor is associated with a controller than can communicate via an interface to a network with the corresponding controllers of the other compressors that are also interfaced to the network. A lead compressor controller may then issue commands to the other compressor controller to more efficiently restore pressure to the system, to implement improved usage schedules, or to manage maintenance intervals to maximize usage of each compressor during periodic maintenance intervals.

Abstract: A brake cylinder having a filament wound composite pressure cylinder and a composite plastic non-pressure head. The pressure cylinder and non-pressure head are secured together by a pair of mating flanges and a V-shaped band securely attached over the flanges. The band has a gap that is easily adjustable to position the gap at the lowest point and be in alignment with a series of radially extending grooves in the flange of the non-pressure head, thereby ensuring proper drainage. The non-pressure head may include an integrally formed an opening with a bearing surface for a piston rod, a seat for a piston return spring, a scraper for a piston rod, and a series of internal ribs that provide for structural support and act as stop against a piston overtravel.

Abstract: An improved air supply control system for a locomotive that includes a global positioning system (GPS) and a track database having the locations of rail road tunnels. Locomotives equipped with one or more air compressors and/or an air dryer are operated by the air supply control system to, firstly, minimize unnecessary air compressor operation in a tunnel and, secondly, to operate only the compressor and air dryer of the lead locomotive in a consist if the air supply system must be operated while the locomotives are in a tunnel.

Abstract: A parking brake control system positioned upstream of a rail car parking brake locking mechanism that prevents the parking brake from disengaging until the braking system recharges to a sufficient point that it can be used to maintain the train on a grade. The system includes a three way valve that reduces the brake pipe pilot pressure supplied to the parking brake unlocking system until the brake pipe pressure reaches a predetermined threshold. A release delay system may be coupled to the parking brake control system to retard the rate at which the parking brakes of rail cars positioned near the head of a train are released to ensure that the parking brakes of the entire train are released at about the same time.

Abstract: An improved air supply control system for a locomotive that includes a global positioning system (GPS) and a track database having the locations of rail road tunnels. Locomotives equipped with one or more air compressors and/or an air dryer are operated by the air supply control system to, firstly, minimize unnecessary air compressor operation in a tunnel and, secondly, to operate only the compressor and air dryer of the lead locomotive in a consist if the air supply system must be operated while the locomotives are in a tunnel.

Abstract: A powered hand brake for locomotive brakes that latches a brake chain into a locked position after the brake cylinder has applied the locomotive brakes. A computer controlled brake system may be interconnected to the brake cylinder and the latch and programmed to set the latch into the latched position when the brake cylinder has moved the locomotive brake into the applied position. An actuator is coupled to the brake chain to take up slack in the brake chain as the brake chain moves between the first and second positions. The actuator can comprise a motor or a tensioning cylinder that takes up slack in the brake chain after the brakes have been applied. Alternatively, the actuator may comprise a linkage connecting the brake chain to the locomotive brake so that the slack in the brake chain is taken up as the brakes are applied.

Abstract: A brake cylinder piston assembly having a composite piston head having a bore formed therethrough, a cup positioned in the bore and coupled to the piston head, and a hollow rod securely welded to the cup. The cup is coupled to the piston head by a series of fingers with locking tabs that extend around the bore of the piston head and engage a rim of the cup. The bore of the piston head has two steps that correspond to the two steps formed into outside of the cup so the two step outer diameter of the cup is securely seated in the two step inner diameter of the bore. A plastic load disc having a hemispherical cavity may be positioned within the end of the hollow rod that is secured to the cup to absorb high energy hand brake releases.

Abstract: An air dryer system for a locomotive having optimized purge air control over a twin tower desiccant-type air dryer. The computer controlled locomotive brake system is used to determine when the air dryer is being used and approximately how much air flow has actually passed through the active tower of the dryer using the air consumption state, the change of pressure in the second main reservoir, the air compressor on/off state, the total accumulated time of air flow since last purge cycle, and/or the calculated air flow through the air dryer since the last purge cycle. When the actual air flow reaches the capacity of the active tower of the air dryer, the computer controlled locomotive brake system commands the air dryer to perform a purge cycle. The system thus maximizes the use of each tower in the air dryer rather than switching according to a preset time period.

Abstract: A system for controlling locomotive compressors in a multiple locomotive consist to optimize compressor life, cold weather operation, and maintenance schedules. Each compressor is associated with a controller than can communicate via an interface to a network with the corresponding controllers of the other compressors that are also interfaced to the network. A lead compressor controller may then issue commands to the other compressor controller to more efficiently restore pressure to the system, to implement improved usage schedules, or to manage maintenance intervals to maximize usage of each compressor during periodic maintenance intervals.

Abstract: An aftercooler bypass system for selectively allowing a portion of the hot compressed gases exiting an air compressor to bypass an aftercooler and intermix with the cooled compressed gases exiting the aftercooler in order to ensure that the cooled compressed gases are above a threshold temperature when the ambient air temperature is at or below freezing. The system includes a valve for controlling the amount of air diverted around the aftercooler and a mixing chamber for allowing the valved air supply to intermix with the aftercooler outlet stream. Temperature sensor may be used to measure ambient air temperature and downstream air temperature to control the opening and closing of the valve and maintain the desired mixed air temperature.

Abstract: A brake cylinder maintaining system produces a brake cylinder reference pressure based on the difference between the brake pipe pressure and the auxiliary reservoir pressure and then feeds that pressure to a choke and a volume so that the ratio of the reference area of the choke to the volume of stored brake cylinder reference pressure is substantively equal to the ratio of a brake cylinder charging valve area to the brake cylinder volume. The resulting reference pressure may be used to adjust brake cylinder pressure by providing the reference pressure to a standard quick service limiting valve or to a relay that can selectively charge or exhaust the brake cylinder.

Abstract: A control system for an air dryer that switches the flow and counter flow of air through each of two desiccant towers in response to a drying cycle period that is proportional to the saturation partial pressure of water vapor in the inlet air stream as determined by the temperature of the stream of air in the inlet of the air dryer. The system may also include a proximity sensor positioned in the back flow check valve between the first main reservoir and the second main reservoir to further adjust the regeneration cycle period according to the flow rate through the air dryer.